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Hunterwood-SY091016Prepared for: City of Coppell 255 Parkway Boulevard Coppell, TX 75019 Attention: Keith Marvin, P.E. October 16, 2009 Prepared by: Pacheco Koch Consulting Engineers 8350 North Central Expressway, Suite 1000 Dallas, TX 75206 Pacheco Koch Consulting Engineers October 16, 2009 PK No.: 2052 - 09.127 Mr. Keith Marvin, P.E. CITY OF COPPELL ENGINEERING DEPARTMENT 255 Parkway Boulevard Coppell, Texas 75019 Re: HUNTERWOOD POCKET PARK FEASIBILITY ANALYSIS OF J4 EROSION CONTROL IMPROVEMENTS Coppell, Texas Dear Mr. Marvin: This report provides a feasibility analysis of proposed improvements for areas downstream of the common area at the Hunterwood Pocket Park. This report summarizes recommendations for erosion control improvements, environmental impacts and probable construction costs. The following attachments document the procedures and findings of the analysis. A narrative text is provided, along with support material in the form of five (5) appendices. This report provides a complete package for your review and approval. If you have any questions regarding the attached report or need any additional information, please contact me at your convenience. Sincerely, Bernard E. Brandon, P.E., CFM BEB /smm 2052 -464 Enc. MW BERNARD E. BRANDON I .$ ;.•. X01940 •;��: lQ /« '? J4 TABLE OF CONTENT 1.0 INTRODUCTION ...................................................................................... ..............................1 1 .1 Authorization ................................................................................ ............................... 1 2.0 PURPOSE ................................................................................................ ..............................1 2.1 Tributary of Grapevine Creek .................................................... ............................... 1 2.2 Vertical Banks ............................................................................... ............................... 1 2.3 Private Property ........................................................................... ............................... 1 2.4 Pedestrian Bridges ....................................................................... ............................... 1 3.0 EXISTING CONDITIONS .......................................................................... ..............................1 3.1 Tributary of Grapevine Creek .................................................... ............................... 1 3.2 Vertical Banks ............................................................................... ............................... 2 3.3 Private Property ........................................................................... ............................... 2 3.4 Pedestrian Bridges ....................................................................... ............................... 3 4.0 ENVIRONMENTAL IMPACTS ................................................................... ..............................4 5.0 MITIGATION MATERIALS AND METHODS .............................................. ..............................5 5.1 Retaining Walls .............................................................................. ..............................5 5.2 Stabilized Slopes - Rock Riprap .................................................. ............................... 6 5.3 Stabilized Slopes - Soft Armoring ............................................... ............................... 7 6.0 RECOMMENDED IMPROVEMENTS ......................................................... ..............................9 6.1 Vertical Banks ............................................................................... ............................... 9 6.2 Private Property ........................................................................... ............................... 9 6.3 Pedestrian Bridges ....................................................................... ............................... 9 Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M: \DWG -20 \2052 -09.127 \Design \Report \FinaLReport.doc i ly APPENDICES Appendix A: Site Map Appendix B: Opinion of Probable Costs Appendix C: City of Coppell Hunterwood Park Improvements Appendix D: Environmental Report Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09.127\Design\Report\Final_Report.doc i J4 LIST OF FIGURES Figure 3.1: Typical Bed Degradation .......................................................... ............................... 2 Figure 3.2: Typical Bed Degradation .......................................................... ............................... 2 Figure 3.3: Near - vertical Banks .................................................................... ............................... 2 Figure Near - vertical Banks .................................................................... ............................... 2 Figure 3.5: Erosion Adjacent Private Property ........................................... ............................... 3 Figure 3.6: Erosion Adjacent Private Property ........................................... ............................... 3 Figure 3.7: Scour at Pedestrian Bridges ...................................................... ............................... 3 Figure 3.8: Scour at Pedestrian Bridges ...................................................... ............................... 3 Figure7: Retaining Wall ................................................................................ ............................... 5 Figure8: Rock Rip Rap .................................................................................. ............................... 6 Figure9: Soft Armoring .................................................................................. ............................... 8 Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09.127\Desfgn\Report\Final-Report.doc iii D 1.0 INTRODUCTION 1.1 Authorization The City of Coppell (City) has requested Pacheco Koch Consulting Engineers (PK) provide recommendations for erosion control improvements to areas immediately downstream of the common area at the Hunterwood Pocket Park (Appendix A). The bank stabilization techniques are described at a conceptual level of detail. To implement the techniques described would require a site specific, detailed design of erosion control measures for each study area. 2.0 PURPOSE 2.1 Tributary of Grapevine Creek - The tributary that runs through the Hunterwood Pocket Park has experienced erosion in several locations. The structural stability of the bank downstream of the common area is a concern and will continue to worsen as time progresses if nothing is done to address the erosion problem. This study does not address the potential to reclaim land areas that have been eroded. 2.2 Vertical Banks - The creek has experienced erosion along much of its bank. The bank erosion has become very steep in several places. The City has requested PK provide recommendations for erosion control improvements and estimates of probable costs for two areas that have severe vertical erosion. 2.3 Private Property - Hunterwood Pocket Park is located in a residential subdivision. In several areas along the creek, sections of the bank have begun sliding into the creek. If the creek bank erosion continues, private property owners adjacent to failing banks could suffer damages to their property. This analysis identifies improvements to reduce creek bank erosion and any potential damage to private property on both sides of the creek. 2.4 Pedestrian Bridges - In some areas the structural stability of the trail and the safety of park patrons has become a concern. Existing soil around the abutments of two pedestrian bridges is being washed away. If the banks on which the bridge supports rest continues to get washed away, the bridges will become unsafe for park users. This analysis includes recommendations for improvements that will reduce the bank erosion at the pedestrian bridges. 3.0 EXISTING CONDITIONS 3.1 Tributary at Grapevine Creek - The limits of this analysis include approximately 1,800 linear feet of the creek. The limits begin downstream of the planned improvements at the park common area near the Anderson Avenue entrance. And end just north of West Bethel Road and Southwest of Brock Street. Based on visual inspection, the creek appears to be an urbanized channel. In this event, increased urban run -off would contribute to creek bed erosion (Fig.'s 3.1 and 3.2). Bed erosion, degradation or lowering, is a process by which the bed of a stream is eroded to a lower level at a much faster rate than occurs naturally. Human activities that alter the magnitude or Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09.127\Design\Report\Final-Report.doc 1 Ily Pacheco Koch Consulting Engineers City of Coppell frequency of creek flow can initiate bed degradation. The varying conditions along the creek would require the use of a combination of erosion control improvements. Figure 3.1 & 3.2 Typical Bed Degradation 3.2 Vertical Banks - Approximately 1,050 feet downstream of the common area, bed degradation contributes to accelerated erosion and bank instability. Bed degradation can cause extensive bank erosion because the bank slope is increased as the stream bed is lowered. The bank slope becomes unstable and contributes to bank failure. Bare and near - vertical banks (Fig.'s 3.3 and 3.4) are signs of bank erosion that will result in sections of the bank sliding into the creek. The two near - vertical banks along the creek are 160 feet and 1 10 feet in length, respectively. The vertical bank, for these areas, range in height from 2 to 15 feet. Effective strategies for combating bank failure involve stopping channel incision through grade control, stabilizing the bank toe and restoring bank vegetation. Figure 3.3 & 3.4 Near - vertical Banks 3.3 Private Property - The creek is surrounded by a residential development. Backfilling the slope with rock riprap re- vegetation within and above the riprap would reduce the erodibility of the areas adjacent private property (Fig.'s 3.5 and 3.6). Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09.127\Design\Report\Final-Repart.doc 2 �u Figure 3.5 and 3.6 Erosion Adjacent Private Property 3.4 Pedestrian Bridges - Local scour is the removal of sediment around bridge abutments by the force of flowing water and the sediment that it carries. As the flow speed increases, the erosive power of flowing water increases and scour may occur. Increases in velocity of the runoff can be the result of natural or human activities. Increased urban run -off can contribute to creek bed degradation which in turn accelerates bank erosion. In order to effectively reduce velocities, the section area downstream of each bridge would have to increase. An effective strategy for combating bank scour would be aimed at re- vegetation and backfilling the bank at the bridge abutments with rock riprap. .it Figure 3.7 & 3.8 Scour at Pedestrian Bridges Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09.127\Design\Report\Finoi_Report.doc 3 V 4.0 ENVIRONMENTAL IMPACTS A limited environmental impact assessment was performed for the planned erosion control improvements at the park common area (Appendix D). The U.S. Corps of Engineers ( USACE) regulates activities that impact jurisdictional waters under the procedures of Section 404 of the Clean Water Act (CWA). PK contracted Integrated Environmental Solutions, LLC (IES) to delineate potential jurisdictional waters and to provide recommendations for proposed improvements to comply with the CWA for the planned improvements at the common area (Appendix C). Any improvements made downstream of the park common area would require an environmental impact assessment. During the environmental assessment for the common area, two tributaries were identified as jurisdictional features within the park. Activities involving filling within jurisdictional water are regulated under Section 404 of the CWA. In order to avoid a lengthy permitting process (3 months to 2 years), the future improvements should be configured to minimize the filling of the tributaries in Hunterwood Park. If the future improvements are configured to minimize the impact area, the improvements can be authorized by the USACE under a Nationwide Permit (NWP). The NWP 13 authorization process would take 3 to 6 months. Activities for erosion control can be authorized under NWP 13 - bank stabilization as long as the improvements do not exceed the limiting criteria for a Pre - Construction Notification (PCN). The limiting criteria for a PCN are: the improvements must be limited to 500 linear in length along the bank, 1 cubic yard of fill per linear foot of bank below the plane of the ordinary high water mark (OHWM) and no discharge of material into wetlands. The total length of bank improvements is limited to 500 feet total bank disturbance for each project. Separate projects must demonstrate independent utility. Or bank improvements will be considered a single project which may require a PCN or individual permit. The planned improvements at the common area included 220 linear feet of bank along the channel within jurisdictional waters. If the length of any future projects were to exceed 280 linear feet along the bank and within jurisdictional waters, the proposed improvements would require a PCN. Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09.127\Design\Report\Finoi_Report.doc 4 IiH 5.0 MITIGATION METHODS AND MATERIALS For the purposes of this study, there are two general approaches to consider for stabilizing streambank: retaining wall or slope stabilization. Retaining wall can be constructed using gabion baskets, reinforced concrete wall, or gravity wall (stacked stone applied to resist the forces applied on a wall). Slope stabilization can be accomplished with hard armoring (i.e. riprap, articulated wall, etc) or soft armoring (i.e. turf reinforcement mats, erosion control blankets, etc). 5.1 Retaining Walls Retaining walls resist lateral pressure and provide support for vertical or near - vertical grade changes (Fig. 7). The bank slope would be backfilled to the design grade, structural elements constructed, and then soil areas re- vegetated. Gabion retaining walls are constructed of large, rock - filled wire cages that can be used to stabilize steep, badly eroding creek banks. For both the creek channel and the areas of near - vertical banks, slope stabilization can be accomplished with gabion retaining wall. The following summarizes advantages and disadvantages of the most suitable option for the area being analyzed. 5.1.1 Where Appropriate Steep banks caused by erosion, slumping or undercutting will require additional stabilizing elements before planted vegetation can become firmly established. In the locations where banks are exceptionally steep and the available setback distance is limited, these more intensive structural elements should be applied to protect the banks. 5.1.2 How to Implement Retaining walls can be constructed of gabions, concrete, stone or timber beams. Concrete walls can (and should where cost permits) be faced with stone or textured to look like rock. This can provide more roughness to slow erosive flood flows. Each of these treatments should be installed during the stream's low water periods to prevent Hunterwood Pocket Park • Erosion Analysis October 16, 20090 5 M: \DWG -20 \2052 -09.127 \Design \Report \Final_Report.doc Figure 7: Retaining Wall a I Pacheco Koch Consulting Engineers City of Coppell disturbance to the stream and simplify construction logistics. Each treatment must include keying the bottom and ends of the structure into the bed and banks. 5.1.3 Advantages Retaining walls provide immediate protection from erosion. Reinforcing action when plants take root, in a terraced wall, results in the formation of stable rows of mixed vegetation. 5.1.4 Disadvantages In order to get construction equipment into the park, the City could have to request temporary access from property owners through their driveways due to the areas of improvement being located in areas that have limited access. 5.1.5 Common Reasons for Failure Not securely keyed into banks and creek bottom. 5.2 Slope Stabilization - Rock Riprap This technique combines a biotechnical approach to bank stabilization with toe placement of sufficiently large rocks to prevent bank washout and scour. This alternative includes backfilling of the slope and re- vegetation within and above the riprap (Fig. 8). This alternative would be effective for stabilizing the banks adjacent to private property and the pedestrian bridge abutments. 5.2.1 Where Appropriate This technique is recommended where erosion problems are pronounced at the toe of the bank and may compromise overall bank or infrastructure stability if not addressed. 5.2.2 How to Implement Excavate portions of bank, as necessary. Re -grade lower portion of bank to a consistent slope. The stones should be at the same angle as the slope of the designed creek bank, and the total thickness of the stone layer should be at least the thickness of two times the rock diameter with design diameter depending on the velocity of the design flow event at that location. If desired, the riprap can be extended up the bank to the Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09. 127 \Design \Report \Finol_Report. doc 6 Figure 8: Rock Riprap elevation of the design flow event. The riprap should extend below the predicted scour level and be on a solid foundation. The rock is underlain with filter layer or geo- textile fabric, which also extends below the scour level and is secured around the lowest rocks. The entire installation should be keyed into the bank at each end to prevent upstream and downstream scour. Vegetation should be planted on the top of the bank, as well as among the riprap. 5.2.3 Advantages Hard armoring provides an immediate stabilizing effect and does not involve more rock than necessary for stabilization. 5.2.4 Disadvantages Hard armoring could be expensive if rock is not available locally. Labor - intensive; requires use of machinery for rock placement. 5.2.5 Common Reasons for Failure Reasons for failure include: rocks being too small, not securely keyed into banks and bottom of adjoining structures and rocks impinging upon pre- construction channel. 5.3 Slope Stabilization - Soft Armoring This alternative uses re- grading and biological techniques to provide bank stabilization. The City requested PK provide recommendations for cost - effective techniques that rely heavily on established vegetation and the mechanical strength of an engineered mesh, fabric or mat. Existing vertical or near - vertical banks would be modified to a moderate (3H: IV or less depending on geotechnical analysis) angle and replanted with native species. Roots of riparian vegetation, rather than structural measures, would provide bank stability. This re- grading will disturb some existing vegetation, but will provide a more stable long -term riparian setting and will improve local hydraulic conveyance. Soft armoring (Fig. 9) may be as simple as seeding and mulching exposed soils, or it could involve re- grading the bank to create a gentler slope and installing turf reinforcement mats. The turf reinforcement mats will also prepare the site to readily accept native plantings or live stakes. The cause and severity of the erosion at various locations along the creek will determine which technique is best suited. Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M: \DWG -20 \2052 -09.127 \Design \Report\Final_Report.doc 7 Figure 9: Soft Armoring my 5.3.1 Where Appropriate Re- grading and replanting is most appropriate on higher portions of the banks, less frequently affected by high flows, or along lower banks where the water velocities are sufficiently low (less than five to seven feet per second) during the design flow event. Re- grading would be necessary where existing slopes are too steep (greater than 3H:1 V) to allow vegetation to become established. 5.3.2 How to Implement Banks will be re- graded, so that the top of bank is located back from the current top of bank. In no cases, should the toe of the re- graded slope extend into the existing channel. Vegetation re- establishment can be accomplished using fabrics, cuttings, seed material, or planting. 5.3.3 Advantages Soft armoring provides extensive aesthetically pleasing re- vegetation and habitat enhancement opportunities. Future root growth will slope stability. 5.3.4 Disadvantages Soft armoring disturbs existing vegetation and soil and is only feasible in areas with good access. Lag time between implementation and stability from established root networks. 5.3.5 Common Reasons for Failure Occurrence of large flood before vegetation is well - established. Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09.127\Design\Reporf\Final-Report.doc 8 ly 6.0 Recommended Improvements 6.1 Vertical Bank (Locations F & H - Site Map) Based on information provided by the City, the areas of near - vertical banks downstream of the common area have been identified as an area of concern. The City has requested PK provide construction costs (Appendix B) for implementing either hard armoring (Option 1) or soft armoring (Option 2) erosion control improvements. Option 1 - Construct 270 linear feet of gabion retaining wall slope protection. In general, a series of low "terraced" walls are preferred to a single high wall. Retaining walls can be stepped progressively so that areas between walls could be backfilled and planted. The banks for the two areas near the park common area were stabilized with stacked rock gabion retaining wall. Riprap aprons were used to stabilize the creek bed and provide toe protection against scour. Based on the design engineer's opinion of probable cost, the cost per linear foot for the improvements is $745. Option 2 - Construct 270 linear feet of turf reinforcement slope protection. Once installed there is little maintenance required. Until the vegetation is fully established, the ground surface should be inspected for signs of erosion below the matting. In order to improve these areas, the channel profile and cross sectional shape would be re- graded to a gentler slope. In addition, adjacent channel banks would be re- graded and slopes engineered and protected with a combination of brush mattresses, erosion control blankets, biodegradable toe protection, and vegetation plantings to stabilize existing banks and highly eroded areas. The cost per linear foot for Option 2 is approximately $375. 6.2 Private Property (Locations A, D & K - Site Map) Option 1 - Construct 150 linear feet of rock riprap slope stabilization. Excavate portions of bank, as necessary and re -grade lower portion of bank to a consistent slope. The total thickness of the stone layer should be at least the thickness of two times the rock diameter. Vegetation should be planted on the top of the bank, as well as among the riprap. Riprap provides an immediate stabilization effect at a competitive cost, but lacks aesthetic appeal. Option 2 - Construct 150 linear feet of turf reinforcement slope protection. Once installed there is little maintenance required. This can be a cost effective solution compared to hard armoring and provides extensive aesthetically pleasing re- vegetation and habitat enhancement opportunities. 6.3 Pedestrian Bridges (Locations E & G - Site Map) Option 1 - Construct 75 linear feet of rock riprap slope stabilization. Install a riprap apron to reduce local scouring at abutments and bed erosion. Riprap provides an immediate stabilization effect at a competitive cost, but lacks aesthetic appeal. Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M: \DWG -20 \2052 -09.127 \Design \Report\Final_Reporf.doc 9 WF Option 2 - Construct 75 linear feet of turf reinforcement slope protection. Install reinforcement mat to reduce local scouring at abutments and bed erosion. This can be a cost effective solution compared to hard armoring and provides extensive aesthetically pleasing re- vegetation and habitat enhancement opportunities. Hunterwood Pocket Park • Erosion Analysis October 16, 2009 M:\DWG-20\2052-09.127\Design\Reporf\Final-Report.doc 10 Appendix A Site Map E3 S b 3g o� v / i i ■ wo •� -0 „ - _ - - -- •al • r r. Y ' ",ITF Ml1F' • • I EAR Iry A AP • • Pachoco Koch C onsulting Eng ineers i DM FU 3051 -M 127n,DWG LOCATION C - TYPICAL BED DEGRADATION '\ I w �s i G% LOCATION J - TYPICAL BED DEGRADATION LOCATION A - PRIVATE PROPERTY LOCATION A - PRFVATE PROPERTY LOCATION / - VERTICAL MMC LOCATION o - pmessim" mot LOCH TION D - PRNATE PROPERTY LOCATION E - PEDESTRIAN BRIDGE LOCATION P - VERTICAL SAAK LOCATION L - AERIAL CROSSING LOCATION H - VERTICAL BANK LOCA TION K - PMVATE PROPERTY Appendix B Opinion of Probable Cost Vertical Bank HUNTERWOOD POCKET PARK Estimate of Probable Cost Vertical Banks - Option 1 Item No. Description Estimated Quantity Unit Unit Price Amount 1 Mobilization LS 1.0 $ 18,300.00 $ 18,300.00 2 Riprap - D 50 = 24" (sacked and placed) CY 201.3 $ 155.00 $ 31,201.50 3 Site Preparation /Access LS 1.0 $ 6,100.00 $ 6,100.00 4 Site Restoration LS 1.0 $ 6,100.00 $ 6,100.00 5 3'x3' PVC Coated Gabions CY 292.8 $ 300.00 $ 87,840.00 6 12" PVC Coated Gabions CY 29.3 $ 225.00 $ 6,588.00 7 Jornamental Iron Fence LF 183.0 $ 45.00 $ 8,235.00 8 lCompacted Fill CY 1 73.2 $ 45.00 $ 3,294.00 Construction Cost Contingency 20% $ 167,658.50 $ 33,531.70 Project Total Vertical Banks - Option 2 $ 201,190.20 Item No. Description Estimated Quantity Unit Unit Price Amount 1 Mobilization LS 1.0 $ 18,300.00 $ 18,300.00 3 Site Preparation /Access LS 1.0 $ 6,100.00 $ 6,100.00 4 Site Restoration LS 1.0 $ 6,100.00 $ 6,100.00 5 Compacted Fill CY 73.2 $ 45.00 $ 3,294.00 6 Turf Reinforcement Mats SY 270.8 $ 70.00 $ 18,958.80 7 Ornamental Fence LF 183.0 $ 45.00 $ 8,235.00 Construction Cost Contingency 20% $ 60,987.80 $ 12,197.56 Project Total $ 73,185.36 Opinion of Costs The opinions of conceptual cost shown, and any resulting conclusions on project finanacial or economic feasibility, have bene prepared for guidance. The final costs of the project will depend on the final design plans, a detailed construction cost estimate, actual labor and material costs, competitive market conditions, actual site conditions, implementation schedule, continuity of personnel and engineering and other variable factors. As a result, the final project costs will vary from the opinions of cost presented herein. Appendix C City of Coppell Hunterwood Park Improvements U i / / t I i ° PROPOSED GROI covER u9 /// 1501F PROPOSED ORNAMENTAL M01 / FENCE (MATCH EXISTMG FENCE ATAREA 4) EXIST. TEMPORARY FENCE (TO BE REMOVED UPONCONFLETIDNOF WALL) •a a� i � .. ..... -'. 4k o6ww _ ' 1 , PROPOSED Rop( R9'IR Y MRS J % i /�� I BACKFLL ARCUND TREE ROOTS WITH CRUSHED STONE / /15 16 NOTCHGABONSASREWIREDTOCLE EXRIMGTREETOOTS DESCRIPTION NORTHING EASTING p BRAG j RETURN GABON AOw 36 MINIMM INTO BANK (TYP.) f NO. PROPOSED FL ELEY. IT OP RIOCK RpflAPI AREA #1 SO- FROM U FSTR AT DO BOWLINE GRA FRpA UPSTREAM TO DOYMBIAEAM ENO) CANNER ROCK RIPIIAP 1 I i 7 I e1N1 eA ' ❑'CUT EET ON THE SOUIMNEST CORNER OF A WRB NLET BEING ON THE EAST ENO OF CLL -DES ON HEATH LANE AND 14DBLEY WAY. ELEV. s6s.a MOB •O'CUr SET ON THE SOUR4 EDGE OFAGAB •KET BEING ON TIE SOUTH END OFCIX-0ESAC ON ANDERSON AVENUE. ELEV.503505 LEGEND PROPOSED GA&OFAS ® PN]Ig9EDROq(RPRAPlMRS I PROPOSED OROIMDCOVER I•AI15 T/G [REV.. TOP OF GABON IIfi9Y EIEY, 1] fFRAa ELM ar0�a PROPOSED GROIMDCOVER I� Flu EXISTIX9 scow HOLE BEI.1D WALL (1EF. BECixX15l- � ;\'\i; � \\ PAVESTONE flETA68N0 WALL (TO REMA•4 s'FENCE ITO NDAAMI� . 4'ci p ^ `G 00 1 so 49 5 / :.ARE;y� � �� al s • : /. Z ;•��' ;�/ 19 �'� 494 ropr wauPi- 1 \ 18 o TOAIpOW DNw4AG Oe 3r D8W Landscape Architects Planners GROIMOCOVER ,rcmW1 \ • 61u 5307 East Mockingbird Lane, Suite 3DD • w Q96 I 29 Dallas, Texas 75206 28 (214) 744 -0757 Fax: 121 41 744-6785 p F¢M v a Austin • Dallas •Houston •San Antonio 4vEnN .6'M•4. 3r eM 3> INTO (TYPJ • END I �� E .Trop TP R OC14 NPN RRO,, 4 A I 1 TO Ts- D) FROM Project: AREA #2 City of Coppell / Hunterwood Park Improvements 9' •]6 DAaC SURVEY CONTROL / CONSTRUCTION STAKING POINTS FT6 DESCRIPTION NORTHING EASTING ELEVATION PT6 DESCRIPTION NORTHING EASTING ELEVATION BMA NO. 622.1385 .7i ' 6 SO- 17 CANNER ROCK RIPIIAP 5973596 57/03000 NATCN Ex. BMB s � 7310366 5702-641 SIX1965 i6 BEGN ROW IGAB93N /FFRI ]511616 564]2226 4310 TO 1 BEGN ROW /GABON /FFRI 633.1956 56302W9 494A TG 19 P.C. /FFRI 7615415 5950.2391 ' 2 P.T. /FFRI 635.01]6 583..52 /- 1TfA810N SLOPE PROTECTON 20 POINTONCUINE /FRi1 ]75.3357 Se SM, ' 5 P,C- /FFRI 8621]/2 584,40& 21 P.T. /FFRI 7775618 5670.3220 a PORRTON CIa1VE /FFRI 61S91N 56535739 22 P.C. /FFRI 7)19256 5877.4222 ' 5 P.T. /FFRI 616,3670 56615095 N END ROW IG,BBION /FFRI 775.6607 SN73B52 ' 8 P.C.IFFRI 6131921 5661.»35 N ENDROW4GABCNiUR4 781.0633 5982.434 S00.0 T'G ] P.LIFFR1 636A92H 5698.6305 25 BEGIN ROW. GASION I ORRA 777.6262 SM75952 500.0 LAi e P,c./FFR1 616,.729 5723.6962 26 BEGMGASION /FRO 767,.80 SBWA573 693.0 TTi 9 P.T. /FFRI 612]363 27 SEGNGABKIN /FF62 759,9080 56426332 198.0 T/G 10 END FXAY 1 GASKM I FFRI 6085506 5711]5]2 26 CORNER ROCK RIMAP 71.732] 5a11.1789 _TCH Ex. 11 CORNER GABON NAT 6273002 574.3080 MATCN a. 29 EDGE ROCK RIPRAP 749.5310 5980.3378 WTCH EX. 12 ENO S X 1.S GABON 6015141 572345] 500.5 TAG m EDGE ROCx R~ MIA791 5960.0388 IMTCN Ex. 13 BEG. T %1' WBON 642.5181 STN.3322 500.S 74 31 EDGE ROOM RIPRAP J87.148 5687,0920 HATCH EX. 14 COMER R RIRAP 832.9158 5623AM9 NATCH EX, W OORNER ROCK RIPnAP ­111 590127/5 WTCH EX. 15 OORNER RDCI(RWRAP mrL 5823902/ MATCH EX. b CORNER ROCK RBNAP 1n.2109 5804.895fi IMTCH EX. 16 CORNER ROCK RIPRAP 620.0178 5636,497 UATCH EX. FFRI •FRONT FACE ROW/ BFR4- eACKFACEROW4 FFRI. FRONr FACE ROW6 W- BACKFACEIOWK IOHTLACATKM TIG.TOPOFOABONELEY. IMTCN EX.. MATCH EXISIN[i GRADE PgBT• Coppell, Texas Project Number: D08710 t . E T- GABIONTOE 9 4 q. B 9 o PRELIMINARY \ NOT FOR CONSTRUCTION THIS DOCUMENT IS ISSUED FOR THE PURPOSE OF 4 BI DD INGONLYUND ERTHEAUTHORITYOFJOELR. CLARK, P,E. 854140.OW 10676. N IS HOT TO BE USED ]OSEDRaEV.(TOPFOCKRKMMPI FORPERM RTINGORCONsTRUCTONPURPOSES. - Designed: JC N Drawn Col ALLAN VIEW NO. PATE SCALE: 1".10' Reviewed: JC a GABION WALL W aPARK GRAPN� SCALE Sheet Number r /� 8... 1 1 L I I 2 U' s � Date Issued: SCA LE N � •,64667 SEPTEMBER 7609 • COI PROPOSED GROUND COVER Lure 12 .• x• -• 4 . EC -1.1 Revisions: 2 _ - /- 1TfA810N SLOPE PROTECTON t . E T- GABIONTOE 9 4 q. B 9 o PRELIMINARY \ NOT FOR CONSTRUCTION THIS DOCUMENT IS ISSUED FOR THE PURPOSE OF 4 BI DD INGONLYUND ERTHEAUTHORITYOFJOELR. CLARK, P,E. 854140.OW 10676. N IS HOT TO BE USED ]OSEDRaEV.(TOPFOCKRKMMPI FORPERM RTINGORCONsTRUCTONPURPOSES. - NO. PATE Sheet Title: GABION WALL PLAN VIEW HUNTERWOOD IDirixi4n9 /H171n61ESIWNNPMMFRD OLDEN �. RTIEELMTE%A975o66 - �� ^ TEL 197212945000 Craig Olden, Inc. -SEWKERAGFA%(072)291266. GABION WALL W aPARK HUNTERWOOD POK Sheet Number r /� 8... 1 1 L I I CITY OFCOPPELL, DALL, TEXAS pESIGN DRAWN DATE SCA LE LE NO. JRC COI SEPT EC -1.1 ANDERSON COURT u'C[OM � O • NI�.903A6 F` "w). -1 HUNTERWOOD PARK -- -- -_ - - LOT 21 1 I I 1 LOT 15 I I 1 I I LOT 14 I I I I I I LOT 22 � 1 I I LOT 19 I I I I I I I I 1 LOT 12 1 I I I I I I I I I 1 LOT 11 1 -- -- - -� / LOT 23 LOT 10 ANDERSON - ' - ly COURT \ o / 0 1 LOT 9 I I _ AREA #2 p eM /e I ���•tt--�� LOT 8 N 733.0369 W E 5702.6461 I r I ELEV. 503.305 M -- -- -- ' HUNTERWOOD PARK LOT 7 D 6M / A '❑' CUT SET ON THE SOUTHWEST COIW EH OF A CURE NEST BEING DN THE xI EAST END OF OUL -DESAC ON HEATH LANE AND MDBLEY WAY. 1 .�0, BMtB •(]- DDFD U, N 5 NLET f1EMG ON THE SOUlH LOT6 I { ....::.... ENO OF CL-0ESAC ON ANOE�AVENUE. EIEV. •pJ.]65 I 566 MOBLEY WAY 1 - -� I � •. U HEATH LANE .:.. A 1 BS\ I kE . A AREA #1 471.6246 Landscape Architects Planners 5307 East Mockingbb e. S d Lanuite 300 Dallas, Texas 75206 12141744 -0757 Fax: 1214) 744-6785 Austin • Dallas • Houston • San Antonio Project: City of Coppell Hunterwood Park Improvements Coppell, Texas Project Number 006710 Designed JC Drawn. C01 Reviewed: JC Date Issued: SEPTEMBER 2009 Revisions: 1 I I ELEV. 505.94 I � N I I / NO. DALE REVISAW Sheet Title •Dluisbn e/INy,wN B.Mr.IM. KIESHAWW PMRY:Iip SURVEY & I LAYOUT OLDEN ,E UE — 0 � Z � R1? - �NTAL S , C r a i g Ol de n, Inc. EASENGNEEWNGRRMq.F.,UB69 FM(M)29. . LAYOUT CONTROL / PRELIMINARY SURVEY /LAYOUT CONTROL HUNTERWOOD / GRAPH SCALE NOT FOR CONSTRUCTION HUNTERWOOD POCKET PARK I Nw_mrtF THIS DOCUMENT IS ISSUED FOR THE PURPOSE OF O UNDER orR MEA URlsno O ro e s CLARK CITY OF COPPELL, DALLAS COUNTY, TEXAS Sheet Number I I / O FOR PERMITTING OR CO . I TISN PURPOSES. DESIGN DRAWN DATE SCALE NOTES "LE NO. I� L EC 1 . 2 I unc co, 2009 r =zD EC -1.2 b 510 Sheet Title: ' GABION WALL OLDEN °' 510 -- 510 " "�"°°° Ol den, Inc. EUB E NGYEENNG RRM N..-I494266. SECTIONS PRELIMINARY GABION WALL SECTIONS HUNTERWOOD NOT FOR CONSTRUCTION HUNTERWOOD POCKET PARK THIS DOCUMENT Is ISSUED FOR THE PURPOSE OF BIDDING ONLY UNDER THE AUTHORITY OF J R. CITY OF COPPELL, DALLAS COUNTY, TEXAS Number Sheet Numb. R P.E. TM ON ON S IS ES FOR PERMTTNIG OR CONSTRTR MRF0 UCTION PURPOSES. FOR PROPOSED GRI COVER, SCALE OTE V FILE NO. 1 EC 1 •3 _ col zoos r'. s' TOPSOIL AND EC -1.3 I. E CONTROL I AT(REF. DE T T (REF. DE SET EC 1.a) S HE E EC 1. ..... _...._. _.._. . .. ... _ ._... .tiETAiL E81A) 505 505 _ _ . r� O GRADE .. 12a ......E TING GRADE IMF.FUIN - -}— a.a 500 7' =� .. 1s xrGAeXNS _ - 500 - .. i MATCH En T1146 GRADE _ 7 X 1 Q11B10114 -' 3 X Mills fi - 6ROW5 .. irmmciA FcApicompAc TriArLEnsr l-0' -off 495 - 31RORSOau - .-. MAILDRV (ASTM 1 495 495 495 IN MIN. 1TMIN. CRL SHED STONE FITER MATERIAL . 4 90 _. _. ... _ .. .. as ;.�. 90 4- - 'i_► RWRAP .. STONE Fil _ _ GEOT EX 'ILE _._.... __... ..... .. ..__ ._. 485 .�, ... PER. ... __.. 4 90 485 SECTION 1 AREA #1 SCALE i' = 5" 495 - ... ... .. :�' 1T MN. CRL SHE STONE el TER mATEPArkt. 490 .__..__. _._. ...WpRiTP ......._._.._ _.. _. ......._._ GEOTE....ILE 505 495 SECTION 3 AREA #1 SCALE : 1" - 5" I r Sheet Title: ' GABION WALL OLDEN °' 510 -- " "�"°°° Ol den, Inc. EUB E NGYEENNG RRM N..-I494266. SECTIONS PRELIMINARY GABION WALL SECTIONS HUNTERWOOD NOT FOR CONSTRUCTION HUNTERWOOD POCKET PARK THIS DOCUMENT Is ISSUED FOR THE PURPOSE OF BIDDING ONLY UNDER THE AUTHORITY OF J R. CITY OF COPPELL, DALLAS COUNTY, TEXAS Number Sheet Numb. R P.E. TM ON ON S IS ES FOR PERMTTNIG OR CONSTRTR MRF0 UCTION PURPOSES. FOR DRAWN DATE SCALE NOTES FILE NO. 1 EC 1 •3 H19-110 col zoos r'. s' TOPSOIL AND EC -1.3 I. ............ - .... ..... _...._. _.._. . .. ... _ ._... .tiETAiL E81A) 505 505 O oil! .. ......E TING GRADE IMF.FUIN - -}— a.a 7' =� 1s _ 500 - .. i GRADE _ 7 X 1 Q11B10114 -' 3 X Mills - 6ROW5 l-0' -off - - - X.S'GAewN_ - 495 495 Ron as ;.�. 'i_► - ice STONE Fil � � . _ _._.... __... ..... .. ..__ ._. .�, ... PER. ... __.. 4 90 ma Mi _ mom 485 485 SECTION 2 AREA #1 SCALE 1' = 5 SECTION 5 AREA #2 SCALE 1"=5" Landscape Architects Planners 5307 East Mockingbird Lane, Suite 300 Dallas, Texas 75206 (2141744 -0757 Fax: (2141744-6785 Austin • Dallas • Houston • San Antonio Project City of Coppell Hunterwood Park Improvements Coppell, Texas Project Number: DD8710 Designed JC Drawn Col Reviewed: JC Date Issued. SEPTEMBER 2009 Revisions: NO. DATE SECTION 4 AREA #1 SCALE : i- = 5" Sheet Title: °DMA "OM.ywtle.Aw PNASN�EEP�O f GABION WALL OLDEN °' 510 -- " "�"°°° Ol den, Inc. EUB E NGYEENNG RRM N..-I494266. SECTIONS PRELIMINARY GABION WALL SECTIONS HUNTERWOOD NOT FOR CONSTRUCTION HUNTERWOOD POCKET PARK THIS DOCUMENT Is ISSUED FOR THE PURPOSE OF BIDDING ONLY UNDER THE AUTHORITY OF J R. CITY OF COPPELL, DALLAS COUNTY, TEXAS Number Sheet Numb. R P.E. TM ON ON S IS ES FOR PERMTTNIG OR CONSTRTR MRF0 UCTION PURPOSES. FOR DRAWN DATE SCALE NOTES FILE NO. 1 EC 1 •3 H19-110 col zoos r'. s' TOPSOIL AND EC -1.3 I. ............ - .... SECTION 4 AREA #1 SCALE : i- = 5" 510 510 -- _ ROPOSED ONN kMENTAL IRON ENCE - OOVER,4'M TOPSOIL AND I. ............ - .... ..... _...._. _.._. . .. ... _ ._... .tiETAiL E81A) 505 505 vARIES .. ......E TING GRADE IMF.FUIN - -}— a.a 500 1s _ 500 - .. MATCH GRADE _ 7 X 1 Q11B10114 -' 3 X :SGASION - 6ROW5 l-0' -off - - - X.S'GAewN_ - 495 495 ,....._ as ;.�. 1T MN. CRU STONE Fil R MATERIA MATB . 490 _._.... __... ..... .. ..__ ._. .�, ... ... __.. 4 90 ma _ ... 485 485 SECTION 2 AREA #1 SCALE 1' = 5 SECTION 4 AREA #1 SCALE : i- = 5" 1.0 GASIONS: "I Gabon aru- consist It redrtpiar, mmwrlmemed, wo-n wke muT basksa filed with store used to buile earth atan,N and -.ion tonool abuot suds u:.b nt, walls, denol finings, h -heals end Sexale - for pipes, slops protection, bridge ravetme -a and weirs. 2.0 MATERIALS 2.1 Gallons shall be prelabriutad in rmrda with ASTM M75-97 W the vze naiad la on the plans, or az athe,nw approved, Gabi,m shall mnsed of gai anized wire or gahanized wire with an aWdion.1 PVC otang -Dean kdo a u Eartn, hexagawl-ahapW doiLle Mist parent with ownilps approximately 3 -114' x 412'. The mash anal W leanmlad in such A mama, As 1' be non­,1v 119 and ro provide he required Iled"sy and shengm. N wie usetl b gabans, ioM6N wdN wire, anal nave a Merge shergM'I 5¢,039 P.SI. to 68.259 P.S.I. n accardanre with ASTM A6419B, Gass ], son IemPer. The no coring snaA meet the requiemena of ASTM a641AB, Class 3, mn temper mdiN sad shat be a minimum quanti( 010.]0'ztl2 br wire O.OBT' in diameter, 0.60 orM2 fa wke 0.106' in diameter, 0.85 ozd12 M wire 0.120' aW 0.131' in damaler aed 0.90 0ztt12lor wiro 0.150 - in diameter. Wm used far galvanized rwPpiN digs shy ed 0.120' aamaa wire per ASTM A641.96 with a tensile Mrerglh d 230 000 P.S.I, to 273.000 P.S.I. par ASTM A]6495. Wre uses la sMrtJess Meal ovedappig d^9a she W 0.120' Owmetr stanless steel wire per ASTM A3t3 -9B. Type 302, Class I with a tensile she,gd, d 322,000 P.S.I. b 253,OW P.S.I. Mean w+re, selvedge wire artd LKIN Wire demisters tar galvanized gab on. aed galvanized gabions wan A PVC mating sing ba n -a- with the remind Ganeters as hated n Table 1, Tde,anros .1 A wire Gamaea shown anal be I/- 0.001, N Casey d wire Isener s seal be prior b tabricahm. TA6LE t - NOMINAL GABgN W/FE DIAMETER, frMniaW Wire ote-aed Wire wish PVC Cos Mesh'Mn g.12J 3 11 0,106 U, 12 W:e 0.150' U, 9 9TsFJ 0.134' PIS 10 w goer us I "I a us l". Pdyviryl C11Mlm (PVC) used b cwt Saban wire any meet the 1-10 -one Awri -liana, Color - gray: Nomnal Thidmass - 0.020 k,Ces; Minimum Thnola,I A - 0.015 aides: W Resistance - 30001eurs using apparates Type E when leased amrdng W ASTM 014% and ASTM G23. San Spay Test - 3000 hours wM Isstad ao -ding 1, ASTM 8117: Abrasion Resisw - weight loss of more man 12 %amormp W ASTM 01242. The PVC marvN shat be unifomiy applied aW snap be Tree nom Hacks, aphis. 6hachW or stressad areas. assembled ga0ion. wit roan a reaa ura with a mninwn mipkneaa or Iwel apnea (1r). rn¢ w,e one aaea are lo oe wp -n nro a angle unit Tlx banam d he end paok soon ce wc(ary mr led to nw body in sucA a manner mat me strarpm and AexipSty at me point of mnneclion is approximatety equal to mat d the mesh TTe ltd tar speaaly fab,,aW gals may be separate conabudipn. The paean shalt bin 6vaed kd' celk 01 APpexinaMy equal size by factory od-ed diaphragm panels usiN mesa d he same"aW gaga as the bod of the gallon. The diaphragm penal, ana be ­A d P props, W,M,n on me base f sdKh a manner Mal no Additional l is ne my. The Wnth d the call anal nth exceed its nonzonral width. N penmeter Woes of the wk. masn fis.*V the body, end .. diaphragm Panels she have A heavle, pauses W d" wire n. the edge of the mesh Pane. N all ed9as of he mesh Panels timing the body, lops of dads anal dw-g- shall as eamref alwchad to A hea i r gauge selvedge wire by A no nmun d two mmpleta rums of the wire mesh ar- Me saver,. wire. Using wire shy be suppliad lo, se , IaMeniy the 9-o,s dale a steps 01 assembly rid ronslruann. UdN wire she be I i�Ided with - gallons n sufficient quantity br thing patine Pam I- oath Ina spec barons. N' other wire Axcep( of the type sulpliad wan Ina Sabah may be used. High tan-'- dapping mss may he used As an anemae laseniy - ad in 11 01 the lie wke 1.11 method -- usedl in aocom -with mass spedfiwtans. GalW.niz W rings sna be used M gel - died paeans bees. .'sal ores Men m dead tar Pvc ... gin no I N IAate -ea era spiral Faarernera may -1 1,1 used. Gallons fiPniaed by a manufadro,r she be If unmet size and - bled to dimension tolls limes of an 5 %. The gallons Mee as pednied by A oten -, wont af6mWd h- Ma marMfacbaer anowi,p mmpkwoe Wnm the spacaicar n h,,r na. 22 Gabon R ock dead to N - gob- NA be clean, bard, durable, l' b 6 wall-g atled Maned lamest- Nit more than 15% of the , (by weight) she Pass 14' oioa i . For tr gedore, 4' b 6 wex-glciad gushed nmest- they be used. The nod, anal W dean and she be stored aW handed n a manner b pro -nl mnounines- 2.3 Gedaxtie Fal- M use as A IMan -a. when spaCngd an me Phra, eha be isx ab, Ina a.- structure as ­­he the *M The 1- to bs used she be M-T., MX1 m app„ -d dwell. 2.4 G-Aw Fixer Muria when aPeadwd m Ina Ple,s. Any lea fNaced ro de Nina as known on me dons. G,Anuw niter thadA any mnasl a crosl,ea Moo n Accormme wen AsrM C33. Sire 57 (1' minus). 25 Back i MalanaL where r.quved behsM Sabiws, anon cgnskt d SaWy Clay (CL) malenal pwmd in 9 ncn maximum loose boa and mrnpaaad b Al lea5195 %max. eo' tl¢nsity per ASTM 0698 (Siardard Proctor) at minus 1 to Plus 1 permnla9e poi s at optimum -,. -an(. AI the Conn -a,', apron, 1 imM1 minus -.nod store Nr material (ASTM C33. S­ 57) may be AubcliNNtl Its Aargy day pmwdad Mat yeotaxtik k placed on Im Of -shed sane and topped on win the mmpzded day cap pr plan. 3.0 CONSTRUCTION: 3.1 Georel- The gad'ns shall be Paalad m aao,danKa with the size, type, and alg- as shown - the Is— PVC - gabins shall he used n the read as 6pecilied and shown an the Plans. The Placement d the gabiors she he h dose mnfo,mdy a the tires ant grades shown on the plans aW shat be in strbl acrordence with these specitcations_ 32 Geotaxtie Fads Plammant - Alter exu -tan to the -bg,am ale -non has been Perbrmad, the gedextile labm (when specified) she aced Ed pl the I- as shown on tlw re Plans. Ca shot be talks of b place the lablc In A manner ex'ee6N the finish ,awn m Me plans. Win- slice. occur, ad,-, pieces of gaa ao eha be ovenapped a minimum d aghleen sahes (1a '). Fabrn she I,e -nod. +Men necessary, by dns ar other suitable mess baton pue, - gabip Excess labr or ..6th put the finished gals- shall be mt an. 3.3 Gallon Assa - Gals Are assembled in M Wwi e Iprg Maps: (I,) Unaild the bskas on A hrd, flat sodxa and su np out all kinks. (2.) Fold! W the front. back. And orb panels and fallen the P.- together with the p.,.N heavy gauge selvage wis by M , th...Wedge wire routs the selvedge wire d the other pane Mo mmplete Nets, (3.) Fuld the - diaphragm panels W and swiss P the sane mama. (4.) Tae sddes at the diaphragms ant ell panes to t h e sides of he gablm by she lying raAMW u specified babe. 34 Tyng Maenad - PROPER TYING OF GM EONS AT ALL STEPS N THE ASSEMBLY AND CONSTRUCTION OF THE GABION STRUCTURE IS CRITICAL TO THE PERFORMANCE OF THE FINISHED GASION STRUCTURE. 1. Gallons thdat be lad in the specified manrer al earn step of mn.trudion. A ) Mow assemdy b) Tykg ro adjacent gabions slay diaphragms all mm W edges c) Tying at Ad to sides d) TynS of lid to lap If e) Re-I'N at cut 9abiore 2. N MN 01 gabana shall be pnrf. a fn the lolowiy mamer (See F,.. t - ahn )'. (,.) Cut a tongth .1 lactrg wire apindo My li- lea lane. (2.) Sawa mA IaciN who onto the gahion a the ell b, rood, ant ,ns.V Me tie wire together. (3.) Procse,, Mng -th daub, to- (made a o same pant) eve? fi -aches At,- The MaAa decd M.uld he punad light"'.go -du N the Mng opal than. (4.) Semnn the oma, ¢otl't me wring war¢ by A to ark .d V me win. amend risen. No'Ine en" except d the t supplied wdh the gahi0ra may be used a, t t ganM 3. Ovedepping rites may m used As an aema(s to ths flied la g w;n, maned whra at aesi onea,a i,xd, (W) o - dap of Me rings nn be them. Spacing d ne rings sna n ady n weir. d m st etl shat lea inches l as a me e-nt a awaan nth Ih'1 oWedap d ma to canmt be abtainW, such as erto-lo-ra yadaom d gabions, ne specified lire eu used 35 Ga0i0n Pavement -Alter each Saban hu bean aasemded A sna be pwoed a posit' ton ¢mph aW Mu1 be eetl ro adlacenl gabions along a mnwdiN edges n rder b norm a mnti-aly ob-led shudural urn. 3.6 Filling Gabbns IT IS CRITICAL TO THE PERFORMANCE OF THE FINISHED GABpN STRUCTURE THAT GABK)NS ARE FILLED TO THEIR MAXIMUM DENSITY WITH VOIDS IN THE GABION MINIMIZED. when Its assembed pnph gAbm,s have been insalad ant had log-,, the gallons she lea tied in the flowing ­­ I . The gaima may be NW by an.l ne. lea shall be Tied n -yea I, His of exceedire I iohea (12'). Care she be taken when PMIN the rod, Mo ha g tteo -s b ns - mat the gabions a,e of damaged o daaged o, bell- Do f Map mck thn a a Height greater than tlaoa lea (a). Suilab, aired and ApEnno s ae machiner ei nap pe deann, b the gabims durbg the Ding operation. Edges of il and diaphragms may be so -ten necessary by tying sea ,einb,pmnent to he edges at the gabos o, o he, auitade guard memanM b We-m dama m del«mar n of the gett 2. Air a Mel- nIh (12 toy. d ,oar has been dauad in 1. cei..1liciam hand mabpuladm for Ina rock shall be penormW m mdmiae Wads and resun P A man and- m -any of mck n the gallon, 3. Gabio,s mat are three feel (31 n9n she have a looped inter lie wire sstaxed in akin cal ­W me non( aW back faces of any unsd Pa to J or exposed wce W h, W sr mkd pons, 0,1 r rte 24' m1m the base or the gallon, (See Fgure 2 - anacreel. Indhaua calk may not be tied to a height gnats, than t E,, index H 2 - ) shove any adi x nl ml untess bopad inner be wires are installed in both d,,M,.s. Gabims Mat are eighteen nd,es (18 high that are i 11ed with axpoea l other Face suds as a reaming wa4 shat ha- a looped ke re senaned mn ling the hunt and back has. Tfa inns fie shall be inhaled at ha I vedicel h,01 or 9' Imn, this base d the gable,. nc,idua cols may not be Neat so a height greater Man nne aches (9') abays an adjacent ult unless looped mer ne woes are inataleo P both direcbans, Inner tie wires vin not mqune0 M Ifi' gallons inhaled as mattress applicatbu. 4. EAdt III- shall b. filed to its maximum density, wbch is slightly highs, Man the sides ant the surface amo0thly leveled mitinnai,g aids. 3.7 Cl sim Gab lO,a - Ana this mck has been leveled, - lab Meal be pad awn red 0 wYM a bar or Ed d Iad umi the edge of Me W aW Iha edge of he gabim are , th. , Cre stall be taken m Mat Me mesh is of defomeE. It slnuM require a Ighl ahetchiN in order to bring Me two Baba- deou sbg,ftr- The haaW prnectin, savage wins of the ltd sna then be twisted around Me heavy savage who on - sides two (2) mmplae lures. The lid -hall men be nod to the saes at he gabao aed the tops of Ina diapta - in the ­-W tying mallgd. The Ids of de gabim5 she also be tad to adiacent gabims airy a Ion edges to ins - the lon of A - do. , mnn..N . dial. S,..W ananli'n shy be given that a1 Proie N sham end, of wire are Nrted in an Me mm gaban 6I,ou,,. 3.6 Cutting Gabims Gabans may be M f form curves r bevels. 0 -dap Me ml pieces AM ref in the specit'ed mane,. Re-tykg shah bs In A manger sin as to peduce A dosed o l when mmdeled. Expels mean -11 snail be cut on or she be "I* xis nearly Laced down Care she lea taken that AN projecting wire aim are hanW ins- m as oft. 4.0 DUAL" CONTROL al Proper o+g a 19abima mdy y Mepa of ron seud�on aro gabana bevy filed w halo maximum mnaih with A mnmum roum of Ydda k m de p.dorma -ce d me 61:6ned gadm Mnlclve. Tlerelore, cwmstiance -In the Iecthnical specil'Kalions wi be ebsely antl tlemughh ispedad. Any work o1 meetiy de impiad wary wit be rejedad. 5.0 MEASUREMENTANDPAYMENi 5.1 Measurement 09ad s(mdures shag Da based on this vddme in w5a yards of gabbns nMaed aad Tiad to - m.xa,um density web A nunan- of .oak aW sna ioNm Ina -lume or amb¢ddae aema wn¢- apocabw. Gabion Mmdure, she be pea 1« at the nhad unit prim Pr dubs' vane. The unit pace shah indutle NI cornet aar- for paong y matenala (91bion,, rock, Boot -4. InIuor panuM finer media) and tw fumi6bre o i Look. labor, Mlulp hers. ant ether n.dentaa -s., ro complete aed Heel Me gad .-rein amdd with the amen, 01 the pwu aW so- fiicenons. GABK)NS MUST BE TIED IN THIS MANNER AT EACH STEP OF CONSTRUCTION, 1. INITIAL ASSEMBLY 2. TYING TO ADJACENT GASIONS ALONG ALL CONTACTING EDGES 3. TYING OF UD TO SIDES 4. TYING OF DD TO ALL DIAPHRAGMS S. RE -TYING OF THE CUT GABION FIGURE 1: TYING METHOD Tl WiiES INNERTIE WIRES SWILL BE PLACED HORIZONTALLY IN EACH GABION CELL EVERY 12' OF VERTICAL HEIGHT CONNECTING THE FRONT (EXTERIOR) AND BACK (INTERIOR) FACES AND ANY UNSUPPORTED FACE LENGTHWISE. FIGURE 2: TIE WIRE INSTALLATION METHOD 0 GABION TYING DETAILS SCALE' NT.S. Landscape Architects Planners 5307 East Mockingbird Lane. Suite 300 Dallas. Texas 75206 121 41 744-0757 Fax: 1214) 744-6785 Austin • Dallas • Houston • San Antonio Project. City of Coppell Hunterwood Park Improvements Coppell, Texas Project Number D08710 Designed. JC Drawn C01 Reviewed: JC Date Issued: SEPTEMBER 2009 Revisions. NO. I DATE REVISION a pweien el NeywW Baker. Ins. 661 E INA- PRAIiE RD OLDEN LITTLE ELM, TEXAS 7- TEL I-) z9a -sgoa PRELIMINARY Olden, Inc. T... ENGINE6IANG R.. NO. F -1 Esa 'As (.142942861 NOT FOR CONSTRUCTION GABION WALL NOTES HUNTERWOOD POCKET PARK THIS DOCUMENT IS ISSUED FOR THE PURPOSE OF BIDDIN G ONLYImDERTHEAUTHORRYOFJOELR, CITY OFCOPPELL, DALLAS COUNTY, TEXAS CLARK, P.E. 654140N 09 /10eXt. IT IS NOT TO BE USED FOR PERMITTING OR CONSTRUCTION PURPOSES. 91RC DRAW N DATE SCALE NOTES FILE LGI Soo' N.T.S. EC -1.4 Sheet Title. GABION WALL NOTES HUNTERWOOD Sheet Number EC 1.4 6.0 ROCK RIPRAP: 6.1 Slone use0 la, rock nprap shell be durable -shad timeMarne with a minimum bulk apednc gravity d 225 u dalermined by TAx w X Stone 6ha1 have A maximum wa lta loss of I Mi 5 rydes d ma9n4AM1n scale sokltion a tJ 14 %inner 5 ,,d S 01 Wdum sulla, Adrian when katW in a-d- with Texdl l -A. 6.2 Stine grada6an Anal be in -ndanm with the lade below' ROCK RIPRAP GRADATION PERCENT ROCK SIZE ROCK WEIGHT SMALLER BY SIZE (INCHES) (LBS) D,m 20 340 DM 6' 250 145 D„ it 15 6.3 Rock riprap anal be - fled to pn. a - -nkmsm wye, o n - ss b the limns shown on the plans. Prior to ple of nil Mrd exuvalfon of channel botlom ra aide slopes shag be made to the subgrado a18va(ion. The t u,91- elevation shah be such that Me lop of he riprap fay. mat,has the chanol Aowlne gradient P the derma inved And matches the existing ground surface al the edg,lIW Imes of the hpmp pratedan. 6.4 Pmr f instau nhan d rock Nrap, an vinal 19 x TO test area shell on installed wilNn plan Imk nor napedan arm WM al by ENieet. Remaidrg,pmp anal not be placed until rest a-b- is nspeaed and approved by En,,. . 6.5 Meaau,emed of rook rhma snag M based on ae wagm tin tonal of r«k deadened m de sea and pwue wain me Imds ir,apalad as Wedree br Huck 6'kela poWiaed daiN ro ma Cit nepnasentaliWa- The um Price shalt kwuds b6 m,yere a i n rot a,annal aaca -tan to m Nrap subside -Inds, n-Ing AW popedy dispo.ire of -.1 anaae. 7.0 GROUND COVER: 7.1 Ground aver shy consist d 4 ncnea minimum l'ps0i, tenmrmy Isodegradegble rosin control mat and oogatbn Nfan Ju-k,e mmaiors planted at a ghteen inch center- bcemer pw.,. Ple -nno. Emits any - 6.0 metmum on slaps behi -abo- gallon poteman 0r as odervdaa indcated on Plants. 72 Temporary G- dyadabe erosion control mat shad! be abmac SC as manufactured by Maccaienn U.S.A. at A,,n -d Aquas, PLce aW samnng mat shy be in amo,drKw wins mrAdaM,ers remmmenmuaa. 7.3 Paymenl for End" aver ana be based on measured area of actual Petaled neat LIMITS OF GROUND COVER I EROSION Z CONTROL MAT (REF. PLANS) a' MIN. TOPSOIL WITH TEMPORARY t^ 1-T �l EROSION CONTROL MAT (REF. NOTES) I .. I f GALLON ASIAN JASMINE PLANTS ON 18' LENTEflS 11 y ' e.­ w w V i 0 w 0 0 6.P MIN. W W W (REF. PLANS w AND SECTIONS) ry- yr w C `0 ° 0 W w i O -0W 0" TOPA'IACKED(3E OF GABIONS W +' 1 4118 _4N r___'N,_GROUND COVER PLANTING DETAIL SCALE : N.T.S. PLAN VIEW `WIRE MESH Appendix D Environmental Report • Integrated Environmental Solutions, LLC Impact Assessment Report I ntegrat ed Environmental Solutions, LLC_ ! 1651 North Collins Boulevard i Suite 170 i Richardson, Texas 75080 T 972.562.7672 i F 972.562.7673 03 August 2009 Mr. Kyle Whitis, P.E. Pacheco Koch Consulting Engineers, Inc. 8350 N. Central Expressway, Suite 1000 Dallas, Texas 75206 -1612 Re: Hunterwood Park Trail Waters of the United States Delineation and Section 404 Permit Assessment Coppell, Dallas County, Texas Dear Mr. Whitis, Integrated Environmental Solutions, LLC. (IES) performed a survey to identify and delineate water features that meet a definition of a water of the United States in Hunterwood Park in the City of Coppell, Dallas County, Texas (Attachment A, Figure 1). This delineation was conducted to ensure compliance with Section 404 of the Clean Water Act (CWA) for the proposed bank stabilization activities along the Hunterwood Park Trail. INTRODUCTION Agencies that regulate impacts to the nation's water resources within Texas include the U.S. Army Corps of Engineers ( USACE), the U.S. Environmental Protection Agency (USEPA), the U.S. Fish and Wildlife Service, and the Texas Commission on Environmental Quality (TCEQ). Jurisdictional waters of the United States are protected under guidelines outlined in Sections 401 and 404 of the CWA, in Executive Order 11990 (Protection of Wetlands), and by the review process of the TCEQ. The USACE has the primary regulatory authority for enforcing Section 404 requirements for waters of the United States, including wetlands. The definition of waters of the United States, in 33 Code of Federal Regulations (CFR) 328.3, includes waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, wetlands, sloughs, wet meadows, or natural ponds and all impoundments of waters otherwise defined as waters of the United States. Also included are wetlands adjacent to waters (other than waters that are themselves wetlands). The term adjacent is defined as bordering, contiguous, or neighboring. Jurisdictional wetlands are a category of waters of the United States and have been defined by the USACE as areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Waters of the United States are defined in 33 CFR 328.3 (a) as: 1. All waters which are currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide; 2. All interstate waters including interstate wetlands; 3. All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sandflats, wetlands, sloughs, prairie potholes, wet meadows, playa lakes, or natural ponds, the use, degradation or destruction of which could affect interstate or foreign commerce including any such waters: i. Which are or could be used by interstate or foreign travelers for recreational or other purposes; or ii. From which fish or shellfish are or could be taken and sold in interstate or foreign commerce; or iii. Which are used or could be used for industrial purpose by industries in interstate commerce; 4. All impoundments of waters otherwise defined as waters of the United States under the definition; 5. Tributaries of waters identified in paragraphs (a)(1) -(4) of this section; 6. The territorial seas; Mr. Kyle Whitis, P.E. Hunterwood Park Trail Delineation — Coppell, Texas 03Auaust2009 Page 2 7. Wetlands adjacent to waters (other than waters that are themselves wetlands) identified in paragraphs 1- 6 above. 8. Waste treatment systems, including treatment ponds or lagoons designed to meet the requirements of CWA (other than cooling ponds as defined in 40 CFR 123.11(m) which also meet the criteria of this definition) are not waters of the United States. On 05 June 2007, the USACE and the USEPA issued joint guidance on delineation of waters on the United States based on the U.S. Supreme Court decisions in Rapanos and Corobell. Under this guidance, potential waters of the United States have been classified as traditional navigable waters (TNW), relatively permanent waters (RPW) (i.e., having flow most of the year or at least seasonally), or non -RPWs. This guidance states that TNWs and RPWs and contiguous or adjacent wetlands to these water features are waters of the United States. Wetlands that are bordering, contiguous, or neighboring another water of the United States is considered adjacent. Additionally, wetlands that are within the 100 -year floodplain of another water of the United States are also considered adjacent. Non -RPWs, wetlands contiguous or adjacent to non -RPWs, and isolated wetlands must undergo a "significant nexus" test on a case -by -case basis to determine the jurisdictional nature of these water features. Under the "significant nexus" test a water feature must have substantial connection to a TNW by direct flow, or by indirect biological, hydrologic, or chemical connection. The new guidance does not void the January 2001 decision of the U.S. Supreme Court in Solid Waste Agency of Northern Cook County (SWANCC) v. USACE which disallowed regulation of isolated wetlands under the CWA through the "Migratory Bird Rule." Previously, the USACE assumed jurisdiction over isolated waters of the United States based on its 1986 preamble stating that migratory birds used these habitats. The "Migratory Bird Rule" provided the nexus to interstate commerce and thus protection under the CWA. However, the new guidance does require that the "significant nexus" test be performed in addition to an analysis of other potential interstate commerce uses for isolated waters. METHODOLOGY Prior to conducting fieldwork, the U.S. Geological Survey (USGS) topographic map; United States Department of Agriculture (USDA) Soil Survey of Dallas County, Texas, the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM); and aerial photographs of the project site were studied to identify possible waters of the United States and areas prone to wetland development. Mr. Shae Kipp of IES conducted the field surveys for potential waters of the United States in accordance with the USACE procedures on 26 June 2009. Wetland delineations were performed on location using the methodology outlined in the 1987 Corps of Engineers Wetland Delineation Manual and the Interim Regional Supplement to the Corps of Engineer Wetland Delineation Manual: Great Plains Region. The presence of wetlands is determined by the positive indication of three criteria (i.e., hydrophytic vegetation, hydrology, and hydric soils). Potential jurisdictional boundaries for other water resources (i.e., non - wetland) were delineated in the field at the ordinary high water mark (OHWM). The 33 CFR 328.3(e) defines OHWM as the line on the shore /bank established by flowing and /or standing water, marked by characteristics such as a clear, natural line impressed on the bank, erosion shelving, changes in the character of soil, destruction of terrestrial vegetation, presence of litter and debris, or other appropriate means that consider the characteristics of the surrounding areas. Photographs were also taken at representative points within the project site (Attachment B). When one or more wetland parameters were encountered, a Wetland Determination Data Form — Great Plains Region taken from the Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual. Great Plains Region was recorded. RESULTS Literature Review The USGS topographic map (Grapevine 7.5- minute Quadrangle, 1982) and the Soil Survey of Dallas County, Texas both illustrate one tributary on the project site. The FEMA FIRM (Map Panel Number 48113C0135 J, effective date 23 August, 2001) illustrates a tributary on the project site which was located within Zones A (Special flood hazard Mr. Kyle Whitis, P.E. Page 3 Hunterwood Park Trail Delineation — Coppell, Texas 03August2009 areas inundated by the 100 -year flood with no base flood elevations determined) and AE (Special flood hazard areas inundated by the 100 -year flood with base flood elevations determined). The Soil Survey of Dallas County, Texas mapped three soil series within the project site — Silawa fine sandy loam, 3 to 8 percent slopes; Axtell fine sandy loam, 1 to 3 percent slopes; Axtell fine sandy loam, 2 to 5 percent slopes. These soil series are not listed on the Hydric Soils of Texas list prepared by the National Technical Committee for Hydric Soils (Revision January 2009). Site Survey The dominant plant communities within the project site, identified during the survey, were a maintained park area and a wooded riparian corridor. The maintained park area consisted of tree species, which included pecan (Carya illinoinensis), eastern redcedar (luniperus virginiono), and American elm (Ulmus americana). The riparian community was dominated primarily by tree cover with limited herbaceous species, which included Canada wildrye (Elymus conadensis) and giant ragweed (Ambrosia trifido). The dominate tree species were Osage orange (Maclura pomifera), green ash (Fraxinus pennsylvonica), American elm, hackberry (Celtis loevigota), and cherrybark oak (Quercus pagoda). During the site survey, three water features (two tributaries and one man -made drainage) were identified on the project site (Attachment A, Figure 2). The general topography of the site was rolling with surface flow draining to the south. The site ranged from 490 feet above mean sea level (amsl) to 510 feet amsl. The overall site drains to the south into Grapevine Creek, which drains into the Elm Fork Trinity River, which ultimately empties into the Trinity River, which is considered a TNW at various reaches. Tributary 1 was a defined channel aligned through the center of the project site initiating outside the project site. The tributary's OHWM measured between three to 18 feet, which was identified by a bed and bank, waterline, and destruction of terrestrial vegetation. The tributary was incised into the landscape between five to 10 feet with no visible groundwater influence throughout the entire reach of this project site. There was flowing water at the time of the field delineation, but this tributary would likely be considered ephemeral and non -RPW due to the stream's location within a relatively small watershed and recent rainfall. The tributary was located within a wooded riparian corridor that extended over the entire project site and was connected to a larger riparian corridor downstream. This riparian corridor provides habitat for a variety of wildlife and detritus from the vegetation provides a partial basis of a food web that supports a wildlife community downstream. Additionally, the forested riparian corridor along the tributary would provide for nutrient and chemical uptake of waters that flow within the channel, as well as water that overtops the channel banks and waters that percolate into the soils. This nutrient and chemical uptake in these waters would provide for a reduced nutrient /chemical loading in the downstream water column. Due to the defined OHWM, indirect biological, chemical, and physical indirect connection to a TNW, the Trinity River, it is IES' professional opinion that Tributary 1 would meet a definition of a water of the United States and therefore be regulated under Section 404 of the CWA. Tributary 2 was a local drainage originating near the adjacent neighborhood, north of Tributary 1. The tributary's OHWM was identified by the destruction of terrestrial vegetation and measured between one to three feet. There was no pooled or flowing water in the tributary at the time of the delineation even though there was a recent rain event. The lack of hydrology within the channel with a recent rain event indicates that the tributary would likely be considered ephemeral and a non -RPW. The tributary was located within a wooded riparian corridor that extended over the entire project site and was connected to a larger riparian corridor downstream. This riparian corridor provides habitat for a variety of wildlife and detritus from the vegetation provides a partial basis of a food web that supports a wildlife community downstream. Additionally, the forested riparian corridor along the tributary would provide for nutrient and chemical uptake of waters that flow within the channel, as well as water that overtops the channel banks and waters that percolate into the soils. This nutrient and chemical uptake in these waters would provide for a reduced nutrient /chemical loading in the downstream water column. Due to the defined OHWMs, indirect biological, chemical, and physical indirect connection to a TNW, the Trinity River, it is IES' professional opinion that Tributary 2 would meet a definition of a water of the United States and therefore be regulated under Section 404 of the CWA. Mr. Kyle Whitis, P. E. Page 4 Hunterwood Park Trail Delineation — Coppell, Texas 03Auaust 2009 Man -made Drainage was a rock - lined, local drainage originating from an underground culvert, north of Tributary 1. The drainage appeared to be the result of the installation of culverts that drain the adjacent community. Review of aerial photographs and USGS topographic maps predating the community show no existing tributaries in the location of this drainage. The lack of supporting data depicting this drainage indicates the drainage is not an historic channel and that it did not take the place of a natural water feature. There is no evidence to support that this man -made drainage feature is replacing a natural feature and, therefore, it is IES' professional opinion that Man -made Drainage would not meet a definition of a water of the United States and would be considered non - jurisdictional. CONCLUSIONS To summarize the delineation, three water features were found in the project site. The Man -made Drainage does not meet a definition of a water of the United States and would be considered non - jurisdictional. Tributary 1 and Tributary 2 meet a definition of a water of the United States since there is an indirect hydrological, biological, and chemical connection to a TNW and would pass a significant nexus test. Section 404 Permitting Activities that result in dredging and /or filling of jurisdictional waters of the United States are regulated under Section 404 of the CWA. The USACE has established Nationwide Permit (NWP) to efficiently authorize common activities that do not significantly impact waters of the United States. The USACE has the responsibility to authorize permitting under a NWP or to require an Individual Permit (IP). The NWPs were recently reissued on 19 March 2007. A summary of NWP — 13 Bank Stabilization (Attachment C) is provided below, along with the notification requirements to the USACE under General Condition 27 (in bold text). NWP 13 —Bank Stabilization. NWP 13 authorizes activities necessary for erosion prevention, provided the activity meets all of the following criteria: A) No material is placed in excess of the minimum needed for erosion protection; B) The activity is no more than 500 feet in length along the bank, unless this criterion is waived in writing by the district engineer; C) The activity will not exceed an average of one cubic yard per running foot placed along the bank below the plane of the OHWM or the high tide line, unless this criterion is waived in writing by the district engineer; D) The activity does not involve discharges of dredged or fill material into special aquatic sites, unless this criterion is waived in writing by the district engineer; E) No material is of the type, or is placed in any location, or in any manner, to impair surface water flow into or out of any water of the United States; F) No material is placed in a manner that will be eroded by normal or expected high flows (properly anchored trees and treetops may be used in low energy areas); and G) The activity is not a stream channelization activity. The concept of the proposed project would be authorized under NWP 13; however, a design specific evaluation was conducted to determine whether or not a pre- construction notification (PCN) following General Condition 27 would be required. In summary, a PCN is required under this NWP if: there is a discharge in a special aquatic site (i.e., wetland), the activity will impact a water of the United States more than 500 linear feet of bank (in total of both all banks), and /or the activity exceeds an average of one cubic yard per running foot placed along the bank below the OHWM. IES has reviewed preliminary design drawings for the proposed bank stabilization activities. The proposed activities involve placement of gabions and rock rip -rap along two sections of the tributary to armor the channel banks. The following summarizes the project in relation to the PCN requirements for NWP 13, which illustrates that the proposed design complies with the criteria of NWP 13 and would not require a PCN under the current design: Mr. Kyle Whitis, P.E. Hunterwood Park Trail Delineation — Coppell, Texas 03August 2009 Page 5 • There are no wetlands or special aquatic sites within the project site, so there will be no discharge into such water features. • The length of the project along the bank of the channel will be 221 linear feet, which is less the 500 -foot threshold. • The bank stabilization activities will have an average of 0.64 cubic yard per running foot placed along the bank below the plane of the OHWM which is less than the 1 cubic yard per running foot threshold. Section 401 Assessment /Best Management Practices Depending upon the final design of the project, it would also be required to comply with the conditions associated with the 401 Water Quality Certification authorized by the TCEQ. On 26 April 2007, the TCEQ conditionally certified that the activities authorized under these NWPs (along with others) should not result in a violation of established Texas Water Quality Standards as required by Section 401 of the CWA and pursuant to Title 30 Texas Administrative Code, Chapter 279 provided that specific conditions are followed (Attachment D). Attachment D provides a list of Best Management Practices (BMP) for erosion control, sediment control, and post construction total suspended solids (TSS) control. The project must implement at least one of the BMPs from erosion control and sediment control categories to comply with Section 401 of the CWA and applicable state laws. IES appreciates the opportunity to work with you and Pacheco Koch Consulting Engineers, Inc., on this project and hope we may be of assistance to you in the future. If you have any comments, questions, or concerns, please do not hesitate to email myself ( SKipp@intenvsol.com ) or Clint Fowler ( CFowleri,@intenvsol.com ) or via telephone at 972/562 -7672. Sincerely, Integrated Environmental Solutions, LLC. MOM Shae Kipp Environmental Specialist Attachments File Ref: 04.002.031 ATTACHMENT A Figures Figure 1 - General Project Location 1� fi F. A tipq , i r 4 y Er r y Gateway , y _ N 1 inch = 1,208 feet Y 0 415 830 1,660 2,490 3,320 Feet coDoetl n Figure 1 - General Project Location ATTACHMENT B Representative Photographs 2. Tributary 1 western area bank erosion, 7. Tributary 2 converging with Tributary 1, facing east 8. Eastern portion of Tributary 1, facing west ATTACHMENT C Nationwide Permit 13 — Bank Stabilization NATIONWIDE PERMIT 13 Bank Stabilization Effective Date: March 19, 2007 (NWP Final Notice, 72 FR 11182, para. 13) Bank Stabilization. Bank stabilization activities necessary for erosion prevention, provided the activity meets all of the following criteria: (a) No material is placed in excess of the minimum needed for erosion protection; (b) The activity is no more than 500 feet in length along the bank, unless this criterion is waived in writing by the district engineer; (c) The activity will not exceed an average of one cubic yard per running foot placed along the bank below the plane of the ordinary high water mark or the high tide line, unless this criterion is waived in writing by the district engineer; (d) The activity does not involve discharges of dredged or fill material into special aquatic sites, unless this criterion is waived in writing by the district engineer; (e) No material is of the type, or is placed in any location, or in any manner, to impair surface water flow into or out of any water of the United States; (f) No material is placed in a manner that will be eroded by normal or expected high flows (properly anchored trees and treetops may be used in low energy areas); and, (g) The activity is not a stream channelization activity. Notification: The permittee must submit a pre- construction notification to the district engineer prior to commencing the activity if the bank stabilization activity: (1) Involves discharges into special aquatic sites; (2) is in excess of 500 feet in length; or (3) will involve the discharge of greater than an average of one cubic yard per running foot along the bank below the plane of the ordinary high water mark or the high tide line. (See general condition 27.) (Sections 10 and 404) NATIONWIDE PERMIT GENERAL CONDITIONS General Conditions: The following general conditions must be followed in order for any authorization by a NWP to be valid: 1. Navigation. (a) No activity may cause more than a minimal adverse effect on navigation. (b) Any safety lights and signals prescribed by the U.S. Coast Guard, through regulations or otherwise, must be installed and maintained at the permittee's expense on authorized facilities in navigable waters of the United States. (c) The permittee understands and agrees that, if future operations by the United States require the removal, relocation, or other alteration, of the structure or work herein authorized, or if, in the opinion of the Secretary of the Army or his authorized representative, said structure or work shall cause unreasonable obstruction to the free navigation of the navigable waters, the permittee will be required, upon due notice from the Corps of Engineers, to remove, relocate, or alter the structural work or obstructions caused thereby, without expense to the United States. No claim shall be made against the United States on account of any such removal or alteration. 2. Aquatic Life Movements. No activity may substantially disrupt the necessary life cycle movements of those species of aquatic life indigenous to the waterbody, including those species that normally migrate through the area, unless the activity's primary purpose is to impound water. Culverts placed in streams must be installed to maintain low flow conditions. 3. Spawning Areas. Activities in spawning areas during spawning seasons must be avoided to the maximum extent practicable. Activities that result in the physical destruction (e.g., through excavation, fill, or downstream smothering by substantial turbidity) of an important spawning area are not authorized. 4. Migratory Bird Breeding Areas. Activities in waters of the United States that serve as breeding areas for migratory birds must be avoided to the maximum extent practicable. 5. Shellfish Beds. No activity may occur in areas of concentrated shellfish populations, unless the activity is directly related to a shellfish harvesting activity authorized by NWPs 4 and 48. 6. Suitable Material. No activity may use unsuitable material (e.g., trash, debris, car bodies, asphalt, etc.). Material used for construction or discharged must be free from toxic pollutants in toxic amounts (see Section 307 of the Clean Water Act), 7. Water Supply Intakes. No activity may occur in the proximity of a public water supply intake, except where the activity is for the repair or improvement of public water supply intake structures or adjacent bank stabilization. 8. Adverse Effects From Impoundments. If the activity creates an impoundment of water, adverse effects to the aquatic system due to accelerating the passage of water, and /or restricting its flow must be minimized to the maximum extent practicable. 9. Management of Water Flows. To the maximum extent practicable, the pre- construction course, condition, capacity, and location of open waters must be maintained for each activity, including stream channelization and storm water management activities, except as provided below. The activity must be constructed to withstand expected high flows. The activity must not restrict or impede the passage of normal or high flows, unless the primary purpose of the activity is to impound water or manage high flows. The activity may alter the pre - construction course, condition, capacity, and location of open waters if it benefits the aquatic environment (e.g., stream restoration or relocation activities). 10. Fills Within 100 -Year Floodplains. The activity must comply with applicable FEMA- approved state or local floodplain management requirements. 11. Equipment. Heavy equipment working in wetlands or mudflats must be placed on mats, or other measures must be taken to minimize soil disturbance. 12. Soil Erosion and Sediment Controls. Appropriate soil erosion and sediment controls must be used and maintained in effective operating condition during construction, and all exposed soil and other fills, as well as any work below the ordinary high water mark or high tide line, must be permanently stabilized at the earliest practicable date. Permittees are encouraged to perform work within waters of the United States during periods of low -flow or no -flow. 13. Removal of Temporary Fills. Temporary fills must be removed in their entirety and the affected areas returned to pre- construction elevations. The affected areas must be revegetated, as appropriate. 14. Proper Maintenance. Any authorized structure or fill shall be properly maintained, including maintenance to ensure public safety. 15. Wild and Scenic Rivers. No activity may occur in a component of the National Wild and Scenic River System, or in a river officially designated by Congress as a "study river" for possible inclusion in the system while the river is in an official study status, unless the appropriate Federal agency with direct management responsibility for such river, has determined in writing that the proposed activity will not adversely affect the Wild and Scenic River designation or study status. Information on Wild and Scenic Rivers may be obtained from the appropriate Federal land management agency in the area (e.g., National Park Service, U.S. Forest Service, Bureau of Land Management, U.S. Fish and Wildlife Service). 16. Tribal Rights. No activity or its operation may impair reserved tribal rights, including, but not limited to, reserved water rights and treaty fishing and hunting rights. 17. Endangered Species. (a) No activity is authorized under any NWP which is likely to jeopardize the continued existence of a threatened authorized under any NWP which "may affect' a listed or endangered species or a species proposed for such designation, as identified under the Federal Endangered Species Act (ESA), or which will destroy or adversely modify the critical habitat of such species. No activity is species or critical habitat, unless Section 7 consultation addressing the effects of the proposed activity has been completed. (b) Federal agencies should follow their own procedures for complying with the requirements of the ESA. Federal permittees must provide the district engineer with the appropriate documentation to demonstrate compliance with those requirements. (c) Non - federal permittees shall notify the district engineer if any listed species or designated critical habitat might be affected or is in the vicinity of the project, or if the project is located in designated critical habitat, and shall not begin work on the activity until notified by the district engineer that the requirements of the ESA have been satisfied and that the activity is authorized. For activities that might affect Federally - listed endangered or threatened species or designated critical habitat, the pre- construction notification must include the name(s) of the endangered or threatened species that may be affected by the proposed work or that utilize the designated critical habitat that may be affected by the proposed work. The district engineer will determine whether the proposed activity "may affect" or will have "no effect" to listed species and designated critical habitat and will notify the non - Federal applicant of the Corps' determination within 45 days of receipt of a complete pre- construction notification. In cases where the non - Federal applicant has identified listed species or critical habitat that might be affected or is in the vicinity of the project, and has so notified the Corps, the applicant shall not begin work until the Corps has provided notification the proposed activities will have "no effect" on listed species or critical habitat, or until Section 7 consultation has been completed. (d) As a result of formal or informal consultation with the FWS or NMFS the district engineer may add species - specific regional endangered species conditions to the NWPs. (e) Authorization of an activity by a NWP does not authorize the "take" of a threatened or endangered species as defined under the ESA. In the absence of separate authorization (e.g., an ESA Section 10 Permit, a Biological Opinion with "incidental take" provisions, etc.) from the U.S. FWS or the NMFS, both lethal and non- lethal "takes" of protected species are in violation of the ESA. Information on the location of threatened and endangered species and their critical habitat can be obtained directly from the offices of the U.S. FWS and NMFS or their worldwide Web pages at http: / /www.fws.gov/ and http : / /www.noaa.gov /fisheries.htmi respectively. 18. Historic Properties. (a) In cases where the district engineer determines that the activity may affect properties listed, or eligible for listing, in the National Register of Historic Places, the activity is not authorized, until the requirements of Section 106 of the National Historic Preservation Act (NHPA) have been satisfied. (b) Federal permittees should follow their own procedures for complying with the requirements of Section 106 of the National Historic Preservation Act. Federal permittees must provide the district engineer with the appropriate documentation to demonstrate compliance with those requirements. (c) Non - federal permittees must submit a pre - construction notification to the district engineer if the authorized activity may have the potential to cause effects to any historic properties listed, determined to be eligible for listing on, or potentially eligible for listing on the National Register of Historic Places, including previously unidentified properties. For such activities, the pre- construction notification must state which historic properties may be affected by the proposed work or include a vicinity map indicating the location of the historic properties or the potential for the presence of historic properties. Assistance regarding information on the location of or potential for the presence of historic resources can be sought from the State Historic Preservation Officer or Tribal Historic Preservation Officer, as appropriate, and the National Register of Historic Places (see 33 CFR 330.4(g)). The district engineer shall make a reasonable and good faith effort to carry out appropriate identification efforts, which may include background research, consultation, oral history interviews, sample field investigation, and field survey. Based on the information submitted and these efforts, the district engineer shall determine whether the proposed activity has the potential to cause an effect on the historic properties. Where the non - Federal applicant has identified historic properties which the activity may have the potential to cause effects and so notified the Corps, the non - Federal applicant shall not begin the activity until notified by the district engineer either that the activity has no potential to cause effects or that consultation under Section 106 of the NHPA has been completed. (d) The district engineer will notify the prospective permittee within 45 days of receipt of a complete pre - construction notification whether NHPA Section 106 consultation is required. Section 106 consultation is not required when the Corps determines that the activity does not have the potential to cause effects on historic properties (see 36 CFR 800.3(a)). If NHPA section 106 consultation is required and will occur, the district engineer will notify the non - Federal applicant that he or she cannot begin work until Section 106 consultation is completed. (e) Prospective permittees should be aware that section 110k of the NHPA (16 U.S.C. 470h -2(k)) prevents the Corps from granting a permit or other assistance to an applicant who, with intent to avoid the requirements of Section 106 of the NHPA, has intentionally significantly adversely affected a historic property to which the permit would relate, or having legal power to prevent it, allowed such significant adverse effect to occur, unless the Corps, after consultation with the Advisory Council on Historic Preservation (ACHP), determines that circumstances justify granting such assistance despite the adverse effect created or permitted by the applicant. If circumstances justify granting the assistance, the Corps is required to notify the ACHP and provide documentation specifying the circumstances, explaining the degree of damage to the integrity of any historic properties affected, and proposed mitigation. This documentation must include any views obtained from the applicant, SHPO/THPO, appropriate Indian tribes if the undertaking occurs on or affects historic properties on tribal lands or affects properties of interest to those tribes, and other parties known to have a legitimate interest in the impacts to the permitted activity on historic properties. 19. Designated Critical Resource Waters. Critical resource waters include, NOAH- designated marine sanctuaries, National Estuarine Research Reserves, state natural heritage sites, and outstanding national resource waters or other waters officially designated by a state as having particular environmental or ecological significance and identified by the district engineer after notice and opportunity for public comment. The district engineer may also designate additional critical resource waters after notice and opportunity for comment. (a) Discharges of dredged or fill material into waters of the United States are not authorized by NWPs 7, 12, 14, 16, 17, 21, 29, 31, 35, 39, 40, 42, 43, 44, 49, and 50 for any activity within, or directly affecting, critical resource waters, including wetlands adjacent to such waters. (b) For NWPs 3, 8, 10, 13, 15, 18, 19, 22, 23, 25, 27, 28, 30, 33, 34, 36, 37, and 38, notification is required in accordance with general condition 27, for any activity proposed in the designated critical resource waters including wetlands adjacent to those waters. The district engineer may authorize activities under these NWPs only after it is determined that the impacts to the critical resource waters will be no more than minimal. 20. Mitigation. The district engineer will consider the following factors when determining appropriate and practicable mitigation necessary to ensure that adverse effects on the aquatic environment are minimal: (a) The activity must be designed and constructed to avoid and minimize adverse effects, both temporary and permanent, to waters of the United States to the maximum extent practicable at the project site (i.e., on site). (b) Mitigation in all its forms (avoiding, minimizing, rectifying, reducing, or compensating) will be required to the extent necessary to ensure that the adverse effects to the aquatic environment are minimal. (c) Compensatory mitigation at a minimum one - for -one ratio will be required for all wetland losses that exceed 1/10 acre and require pre - construction notification, unless the district engineer determines in writing that some other form of mitigation would be more environmentally appropriate and provides a project - specific waiver of this requirement. For wetland losses of 1 /10 acre or less that require pre - construction notification, the district engineer may determine on a case -by -case basis that compensatory mitigation is required to ensure that the activity results in minimal adverse effects on the aquatic environment. Since the likelihood of success is greater and the impacts to potentially valuable uplands are reduced, wetland restoration should be the first compensatory mitigation option considered. (d) For losses of streams or other open waters that require pre- construction notification, the district engineer may require compensatory mitigation, such as stream restoration, to ensure that the activity results in minimal adverse effects on the aquatic environment. (e) Compensatory mitigation will not be used to increase the acreage losses allowed by the acreage limits of the NWPs. For example, if an NWP has an acreage limit of 1/2 acre, it cannot be used to authorize any project resulting in the loss of greater than 1/2 acre of waters of the United States, even if compensatory mitigation is provided that replaces or restores some of the lost waters. However, compensatory mitigation can and should be used, as necessary, to ensure that a project already meeting the established acreage limits also satisfies the minimal impact requirement associated with the NWPs. (f) Compensatory mitigation plans for projects in or near streams or other open waters will normally include a requirement for the establishment, maintenance, and legal protection (e.g., conservation easements) of riparian areas next to open waters. In some cases, riparian areas may be the only compensatory mitigation required. Riparian areas should consist of native species. The width of the required riparian area will address documented water quality or aquatic habitat loss concerns. Normally, the riparian area will be 25 to 50 feet wide on each side of the stream, but the district engineer may require slightly wider riparian areas to address documented water quality or habitat loss concerns. Where both wetlands and open waters exist on the project site, the district engineer will determine the appropriate compensatory mitigation (e.g., riparian areas and /or wetlands compensation) based on what is best for the aquatic environment on a watershed basis. In cases where riparian areas are determined to be the most appropriate form of compensatory mitigation, the district engineer may waive or reduce the requirement to provide wetland compensatory mitigation for wetland losses. (g) Permittees may propose the use of mitigation banks, in -lieu fee arrangements or separate activity - specific compensatory mitigation. In all cases, the mitigation provisions will specify the party responsible for accomplishing and /or complying with the mitigation plan. (h) Where certain functions and services of waters of the United States are permanently adversely affected, such as the conversion of a forested or scrub -shrub wetland to a herbaceous wetland in a permanently maintained utility line right -of -way, mitigation may be required to reduce the adverse effects of the project to the minimal level. 21. Water Quality. Where States and authorized Tribes, or EPA where applicable, have not previously certified compliance of an NWP with CWA Section 401, individual 401 Water Quality Certification must be obtained or waived (see 33 CFR 330.4(c)). The district engineer or State or Tribe may require additional water quality 4 management measures to ensure that the authorized activity does not result in more than minimal degradation of water quality. 22. Coastal Zone Management. In coastal states where an NWP has not previously received a state coastal zone management consistency concurrence, an individual state coastal zone management consistency concurrence must be obtained, or a presumption of concurrence must occur (see 33 CFR 330.4(d)). The district engineer or a State may require additional measures to ensure that the authorized activity is consistent with state coastal zone management requirements. 23. Regional and Case -By -Case Conditions. The activity must comply with any regional conditions that may have been added by the Division Engineer (see 33 CFR 330.4(e)) and with any case specific conditions added by the Corps or by the state, Indian Tribe, or U.S. EPA in its section 401 Water Quality Certification, or by the state in its Coastal Zone Management Act consistency determination. 24. Use of Multiple Nationwide Permits. The use of more than one NWP for a single and complete project is prohibited, except when the acreage loss of waters of the United States authorized by the NWPs does not exceed the acreage limit of the NWP with the highest specified acreage limit. For example, if a road crossing, over tidal waters is constructed under NWP 14, with associated bank stabilization authorized by NWP 13, the maximum acreage loss of waters of the United States for the total project cannot exceed 1/3-acre. 25. Transfer of Nationwide Permit Verifications. If the permittee sells the property associated with the nationwide permit verification, the permittee may transfer the nationwide permit verification to the new owner by submitting a letter to the appropriate Corps district office to validate the transfer. A copy of the nationwide permit verification must be attached to the letter, and the letter must contain the following statement and signature: "When the structures or work authorized by this nationwide permit are still in existence at the time the property is transferred, the terms and conditions of this nationwide permit, including any special conditions, will continue to be binding on the new owner(s) of the property. To validate the transfer of this nationwide permit, and the associated liabilities associated with compliance with its terms and conditions, have the transferee sign and date below." (Transferee) (Date) 26. Compliance Certification. Each permittee who received the NWP verification from the Corps must submit a signed certification regarding the completed work and any required mitigation. The certification form must be forwarded by the Corps with the NWP verification letter and will include: (a) A statement that the authorized work was done in accordance with the NWP authorization, including any general or specific conditions; (b) A statement that any required mitigation was completed in accordance with the permit conditions; and (c) The signature of the permittee certifying the completion of the work and mitigation. 27. Pre - Construction Notification. (a) Timing. Where required by the terms of the NWP, the prospective permittee must notify the district engineer by submitting a pre - construction notification (PCN) as early as possible. The district engineer must determine if the PCN is complete within 30 calendar days of the date of receipt and, as a general rule, will request additional information necessary to make the PCN complete only once. However, if the prospective permittee does not provide all of the requested information, then the district engineer will notify the prospective permittee that the PCN is still incomplete and the PCN review process will not commence until all of the requested information has been received by the district engineer. The prospective permittee shall not begin the activity until either: (1) He or she is notified in writing by the district engineer that the activity may proceed under the NWP with any special conditions imposed by the district or division engineer; or (2) Forty-five calendar days have passed from the district engineer's receipt of the complete PCN and the prospective permittee has not received written notice from the district or division engineer. However, if the permittee was required to notify the Corps pursuant to general condition 17 that listed species or critical habitat might affected or in the vicinity of the project, or to notify the Corps pursuant to general condition 18 that the activity may have the potential to cause effects to historic properties, the permittee cannot begin the activity until receiving written notification from the Corps that is "no effect" on listed species or "no potential to cause effects" on historic properties, or that any consultation required under Section 7 of the Endangered Species Act (see 33 CFR 330.4(f)) and /or Section 106 of the National Historic Preservation (see 33 CFR 330.4(g)) is completed. Also, work cannot begin under NWPs 21, 49, or 50 until the permittee has received written approval from the Corps. If the proposed activity requires a written waiver to exceed specified limits of an NWP, the permittee cannot begin the activity until the district engineer issues the waiver. If the district or division engineer notifies the permittee in writing that an individual permit is required within 45 calendar days of receipt of a complete PCN, the permittee cannot begin the activity until an individual permit has been obtained. Subsequently, the permittee's right to proceed under the NWP may be modified, suspended, or revoked only in accordance with the procedure set forth in 33 CFR 330.5(d)(2). (b) Contents of Pre - Construction Notification: The PCN must be in writing and include the following information: (1) Name, address and telephone numbers of the prospective permittee; (2) Location of the proposed project; (3) A description of the proposed project; the project's purpose; direct and indirect adverse environmental effects the project would cause; any other NWP(s), regional general permit(s), or individual permit(s) used or intended to be used to authorize any part of the proposed project or any related activity. The description should be sufficiently detailed to allow the district engineer to determine that the adverse effects of the project will be minimal and to determine the need for compensatory mitigation. Sketches should be provided when necessary to show that the activity complies with the terms of the NWP. (Sketches usually clarify the project and when provided result in a quicker decision.); (4) The PCN must include a delineation of special aquatic sites and other waters of the United States on the project site. Wetland delineations must be prepared in accordance with the current method required by the Corps. The permittee may ask the Corps to delineate the special aquatic sites and other waters of the United States, but there may be a delay if the Corps does the delineation, especially if the project site is large or contains many waters of the United States. Furthermore, the 45 day period will not start until the delineation has been submitted to or completed by the Corps, where appropriate; (5) If the proposed activity will result in the loss of greater than 1/10 acre of wetlands and a PCN is required, the prospective permittee must submit a statement describing how the mitigation requirement will be satisfied. As an alternative, the prospective permittee may submit a conceptual or detailed mitigation plan. (6) If any listed species or designated critical habitat might be affected or is in the vicinity of the project, or if the project is located in designated critical habitat, for non - Federal applicants the PCN must include the name(s) of those endangered or threatened species that might be affected by the proposed work or utilize the designated critical habitat that may be affected by the proposed work. Federal applicants must provide documentation demonstrating compliance with the Endangered Species Act; and (7) For an activity that may affect a historic property listed on, determined to be eligible for listing on, or potentially eligible for listing on, the National Register of Historic Places, for non - Federal applicants the PCN must state which historic property may be affected by the proposed work or include a vicinity map indicating the location of the historic property. Federal applicants must provide documentation demonstrating compliance with Section 106 of the National Historic Preservation Act. (c) Form of Pre - Construction Notification: The standard individual permit application form (Form ENG 4345) may be used, but the completed application form must clearly indicate that it is a PCN and must include all of the information required in paragraphs (b)(1) through (7) of this general condition. A letter containing the required information may also be used. (d) Agency Coordination: (1) The district engineer will consider any comments from Federal and state agencies concerning the proposed activity's compliance with the terms and conditions of the NWPs and the need for mitigation to reduce the project's adverse environmental effects to a minimal level. (2) For all NWP 48 activities requiring pre - construction notification and for other NWP activities requiring pre- construction notification to the district engineer that result in the loss of greater than 1/2 -acre of waters of the United States, the district engineer will immediately provide (e.g., via facsimile transmission, overnight mail, or other expeditious manner) a copy of the PCN to the appropriate Federal or state offices (U.S. FWS, state natural resource or water quality agency, EPA, State Historic Preservation Officer (SHPO) or Tribal Historic Preservation Office (THPO), and, if appropriate, the NMFS). With the exception of NWP 37, these agencies will then have 10 calendar days from the date the material is transmitted to telephone or fax the district engineer notice that they intend to provide substantive, site - specific comments. If so contacted by an agency, the district engineer will wait an additional 15 calendar days before making a decision on the pre - construction notification. The district engineer will fully consider agency comments received within the specified time frame, but will provide no response to the resource agency, except as provided below. The district engineer will indicate in the administrative record associated with each pre- construction notification that the resource agencies' concerns were considered. For 6 NWP 37, the emergency watershed protection and rehabilitation activity may proceed immediately in cases where there is an unacceptable hazard to life or a significant loss of property or economic hardship will occur. The district engineer will consider any comments received to decide whether the NWP 37 authorization should be modified, suspended, or revoked in accordance with the procedures at 33 CFR 330.5. (3) In cases of where the prospective permittee is not a Federal agency, the district engineer will provide a response to NMFS within 30 calendar days of receipt of any Essential Fish Habitat conservation recommendations, as required by Section 305(b)(4)(B) of the Magnuson- Stevens Fishery Conservation and Management Act. (4) Applicants are encouraged to provide the Corps multiple copies of pre- construction notifications to expedite agency coordination. (5) For NWP 48 activities that require reporting, the district engineer will provide a copy of each report within 10 calendar days of receipt to the appropriate regional office of the NMFS. (e) District Engineer's Decision: In reviewing the PCN for the proposed activity, the district engineer will determine whether the activity authorized by the NWP will result in more than minimal individual or cumulative adverse environmental effects or may be contrary to the public interest. If the proposed activity requires a PCN and will result in a loss of greater than 1/10 acre of wetlands, the prospective permittee should submit a mitigation proposal with the PCN. Applicants may also propose compensatory mitigation for projects with smaller impacts. The district engineer will consider any proposed compensatory mitigation the applicant has included in the proposal in determining whether the net adverse environmental effects to the aquatic environment of the proposed work are minimal. The compensatory mitigation proposal may be either conceptual or detailed. If the district engineer determines that the activity complies with the terms and conditions of the NWP and that the adverse effects on the aquatic environment are minimal, after considering mitigation, the district engineer will notify the permittee and include any conditions the district engineer deems necessary. The district engineer must approve any compensatory mitigation proposal before the permittee commences work. If the prospective permittee elects to submit a compensatory mitigation plan with the PCN, the district engineer will expeditiously review the proposed compensatory mitigation plan_ The district engineer must review the plan within 45 calendar days of receiving a complete PCN and determine whether the proposed mitigation would ensure no more than minimal adverse effects on the aquatic environment. If the net adverse effects of the project on the aquatic environment (after consideration of the compensatory mitigation proposal) are determined by the district engineer to be minimal, the district engineer will provide a timely written response to the applicant. The response will state that the project can proceed under the terms and conditions of the NWP. If the district engineer determines that the adverse effects of the proposed work are more than minimal, then the district engineer will notify the applicant either: (1) That the project does not qualify for authorization under the NWP and instruct the applicant on the procedures to seek authorization under an individual permit; (2) that the project is authorized under the NWP subject to the applicant's submission of a mitigation plan that would reduce the adverse effects on the aquatic environment to the minimal level; or (3) that the project is authorized under the NWP with specific modifications or conditions. Where the district engineer determines that mitigation is required to ensure no more than minimal adverse effects occur to the aquatic environment, the activity will be authorized within the 45 -day PCN period. The authorization will include the necessary conceptual or specific mitigation or a requirement that the applicant submit a mitigation plan that would reduce the adverse effects on the aquatic environment to the minimal level. When mitigation is required, no work in waters of the United States may occur until the district engineer has approved a specific mitigation plan. 28. Single and Complete Project. The activity must be a single and complete project. The same NWP cannot be used more than once for the same single and complete project. Further Information 1, District Engineers have authority to determine if an activity complies with the terms and conditions of an NWP. 2. NWPs do not obviate the need to obtain other federal, state, or local permits, approvals, or authorizations required by law. 3. NWPs do not grant any property rights or exclusive privileges. 4. NWPs do not authorize any injury to the property or rights of others. 5. NWPs do not authorize interference with any existing or proposed Federal project. Definitions Best management practices (BMPs): Policies, practices, procedures, or structures implemented to mitigate the adverse environmental effects on surface water quality resulting from development. BMPs are categorized as structural or non - structural. Compensatory mitigation: The restoration, establishment (creation), enhancement, or preservation of aquatic resources for the purpose of compensating for unavoidable adverse impacts which remain after all appropriate and practicable avoidance and minimization has been achieved. Currently serviceable: Useable as is or with some maintenance, but not so degraded as to essentially require reconstruction. Discharge: The term "discharge" means any discharge of dredged or fill material. Enhancement: The manipulation of the physical, chemical, or biological characteristics of an aquatic resource to heighten, intensify, or improve a specific aquatic resource function(s). Enhancement results in the gain of selected aquatic resource function(s), but may also lead to a decline in other aquatic resource function(s). Enhancement does not result in a gain in aquatic resource area. Ephemeral stream: An ephemeral stream has flowing water only during, and for a short duration after, precipitation events in a typical year. Ephemeral stream beds are located above the water table year- round. Groundwater is not a source of water for the stream. Runoff from rainfall is the primary source of water for stream flow. Establishment (creation): The manipulation of the physical, chemical, or biological characteristics present to develop an aquatic resource that did not previously exist at an upland site. Establishment results in a gain in aquatic resource area. Historic Property: Any prehistoric or historic district, site (including archaeological site), building, structure, or other object included in, or eligible for inclusion in, the National Register of Historic Places maintained by the Secretary of the Interior. This term includes artifacts, records, and remains that are related to and located within such properties. The term includes properties of traditional religious and cultural importance to an Indian tribe or Native Hawaiian organization and that meet the National Register criteria (36 CFR Part 60). Independent utility: A test to determine what constitutes a single and complete project in the Corps regulatory program. A project is considered to have independent utility if it would be constructed absent the construction of other projects in the project area. Portions of a multi -phase project that depend upon other phases of the project do not have independent utility. Phases of a project that would be constructed even if the other phases were not built can be considered as separate single and complete projects with independent utility. Intermittent stream: An intermittent stream has flowing water during certain times of the year, when groundwater provides water for stream flow. During dry periods, intermittent streams may not have flowing water. Runoff from rainfall is a supplemental source of water for stream flow. Loss of waters of the United States: Waters of the United States that are permanently adversely affected by filling, flooding, excavation, or drainage because of the regulated activity. Permanent adverse effects include permanent discharges of dredged or fill material that change an aquatic area to dry land, increase the bottom elevation of a waterbody, or change the use of a waterbody. The acreage of loss of waters of the United States is a threshold measurement of the impact to jurisdictional waters for determining whether a project may qualify for an NWP; it is not a net threshold that is calculated after considering compensatory mitigation that may be used to offset losses of aquatic functions and services. The loss of stream bed includes the linear feet of stream bed that is filled or excavated. Waters of the United States temporarily filled, flooded, excavated, or drained, but restored to pre- construction contours and elevations after construction, are not included in the measurement of loss of waters of the United States. Impacts resulting from activities eligible for exemptions under Section 404(f) of the Clean Water Act are not considered when calculating the loss of waters of the United States. Non -tidal wetland: A non -tidal wetland is a wetland that is not subject to the ebb and flow of tidal waters. The definition of a wetland can be found at 33 CFR 328.3(b). Non -tidal wetlands contiguous to tidal waters are located landward of the high tide line (i.e., spring high tide line). Open water: For purposes of the NWPs, an open -water is any area that in a year with normal patterns of precipitation has water flowing or standing above ground to the extent that an ordinary high water mark can be determined. Aquatic vegetation within the area of standing or flowing water is either non - emergent, sparse, or absent. Vegetated shallows are considered to be open waters. Examples of "open waters" include rivers, streams, lakes, and ponds. Ordinary High Water Mark: An ordinary high water mark is a line on the shore established by the fluctuations of water and indicated by physical characteristics, or by other appropriate means that consider the characteristics of the surrounding areas (see 33 CFR 328.3(e))_ Perennial stream: A perennial stream has flowing water year -round during a typical year. The water table is located above the stream bed for most of the year. Groundwater is the primary source of water for stream flow. Runoff from rainfall is a supplemental source of water for stream flow. Practicable: Available and capable of being done after taking into consideration cost, existing technology, and logistics in light of overall project purposes. Pre - construction notification: A request submitted by the project proponent to the Corps for confirmation that a particular activity is authorized by nationwide permit. The request may be a permit application, letter, or similar document that includes information about the proposed work and its anticipated environmental effects. Pre - construction notification may be required by the terms and conditions of a nationwide permit, or by regional conditions. A pre- construction notification may be voluntarily submitted in cases where pre- construction notification is not required and the project proponent wants confirmation that the activity is authorized by nationwide permit. Preservation: The removal of a threat to, or preventing the decline of, aquatic resources by an action in or near those aquatic resources. This term includes activities commonly associated with the protection and maintenance of aquatic resources through the implementation of appropriate legal and physical mechanisms. Preservation does not result in a gain of aquatic resource area or functions. Re- establishment: The manipulation of the physical, chemical, or biological characteristics of a site with the goal of returning natural /historic functions to a former aquatic resource. Re- establishment results in rebuilding a former aquatic resource and results in a gain in aquatic resource area. Rehabilitation: The manipulation of the physical, chemical, or biological characteristics of a site with the goal of repairing natural /historic functions to a degraded aquatic resource. Rehabilitation results in a gain in aquatic resource function, but does not result in a gain in aquatic resource area. Restoration: The manipulation of the physical, chemical, or biological characteristics of a site with the goal of returning natural /historic functions to a former or degraded aquatic resource. For the purpose of tracking net gains in aquatic resource area, restoration is divided into two categories: Re- establishment and rehabilitation. Riffle and pool complex: Riffle and pool complexes are special aquatic sites under the 404(b)(1) Guidelines_ Riffle and pool complexes sometimes characterize steep gradient sections of streams. Such stream sections are recognizable by their hydraulic characteristics. The rapid movement of water over a course substrate in riffles results in a rough flow, a turbulent surface, and high dissolved oxygen levels in the water. Pools are deeper areas associated with riffles. A slower stream velocity, a streaming flow, a smooth surface, and a finer substrate characterize pools. Riparian areas: Riparian areas are lands adjacent to streams, lakes, and estuarine - marine shorelines. Riparian areas are transitional between terrestrial and aquatic ecosystems, through which surface and subsurface hydrology connects waterbodies with their adjacent uplands. Riparian areas provide a variety of ecological functions and services and help improve or maintain local water quality. (See general condition 20.) Shellfish seeding: The placement of shellfish seed and /or suitable substrate to increase shellfish production. Shellfish seed consists of immature individual shellfish or individual shellfish attached to shells or shell fragments (Le., spat on shell). Suitable substrate may consist of shellfish shells, shell fragments, or other appropriate materials placed into waters for shellfish habitat. Single and complete project: The term "single and complete project' is defined at 33 CFR 330.2(1) as the total project proposed or accomplished by one owner /developer or partnership or other association of owners /developers. A single and complete project must have independent utility (see definition). For linear projects, a "single and complete project' is all crossings of a single water of the United States (i.e., a single waterbody) at a specific location. For linear projects crossing a single waterbody several times at separate and distant locations, each crossing is considered a single and complete project. However, individual channels in a braided stream or river, or individual arms of a large, irregularly shaped wetland or lake, etc., are not separate waterbodies, and crossings of such features cannot be considered separately. Stormwater management: Stormwater management is the mechanism for controlling stormwater runoff for the purposes of reducing downstream erosion, water quality degradation, and flooding and mitigating the adverse effects of changes in land use on the aquatic environment. Stormwater management facilities: Stormwater management facilities are those facilities, including but not limited to, stormwater retention and detention ponds and best management practices, which retain water for a period of time to control runoff and /or improve the quality (i.e., by reducing the concentration of nutrients, sediments, hazardous substances and other pollutants) of stormwater runoff. Stream bed: The substrate of the stream channel between the ordinary high water marks. The substrate may be bedrock or inorganic particles that range in size from clay to boulders. Wetlands contiguous to the stream bed, but outside of the ordinary high water marks, are not considered part of the stream bed. N Stream channelization: The manipulation of a stream's course, condition, capacity, or location that causes more than minimal interruption of normal stream processes. A channelized stream remains a water of the United States. Structure: An object that is arranged in a definite pattern of organization. Examples of structures include, without limitation, any pier, boat dock, boat ramp, wharf, dolphin, weir, boom, breakwater, bulkhead, revetment, riprap, jetty, artificial island, artificial reef, permanent mooring structure, power transmission line, permanently moored floating vessel, piling, aid to navigation, or any other manmade obstacle or obstruction. Tidal wetland: A tidal wetland is a wetland (i.e., water of the United States) that is inundated by tidal waters. The definitions of a wetland and tidal waters can be found at 33 CFR 328.3(b) and 33 CFR 328.3(f), respectively. Tidal waters rise and fall in a predictable and measurable rhythm or cycle due to the gravitational pulls of the moon and sun. Tidal waters end where the rise and fall of the water surface can no longer be practically measured in a predictable rhythm due to masking by other waters, wind, or other effects. Tidal wetlands are located channelward of the high tide line, which is defined at 33 CFR 328.3(d). Vegetated shallows: Vegetated shallows are special aquatic sites under the 404(b)(1) Guidelines. They are areas that are permanently inundated and under normal circumstances have rooted aquatic vegetation, such as seagrasses in marine and estuarine systems and a variety of vascular rooted plants in freshwater systems. Waterbody: For purposes of the NWPs, a waterbody is a jurisdictional water of the United States that, during a year with normal patterns of precipitation, has water flowing or standing above ground to the extent that an ordinary high water mark (OHWM) or other indicators of jurisdiction can be determined, as well as any wetland area (see 33 CFR 328.3(b)). If a jurisdictional wetland is adjacent -- meaning bordering, contiguous, or neighboring - -to a jurisdictional waterbody displaying an OHWM or other indicators of jurisdiction, that waterbody and its adjacent wetlands are considered together as a single aquatic unit (see 33 CFR 328.4(c)(2)). Examples of "waterbodies" include streams, rivers, lakes, ponds, and wetlands. ADDITIONAL INFORMATION This nationwide permit is effective March 19, 2007, and expires on March 18, 2012. Information about the U.S. Army Corps of Engineers regulatory program, including nationwide permits, may also be accessed at http : / /www.swf.usace. army. mil /pubdata /environ /regulatory /index asp or hftp:/Avvvw.usace.armv.mil/cw/cecwo/reg 1111 ATTACHMENT D 401 Water Quality Certification Best Management Practices ti Texas Commission on Environmental Quality 401 Water Quality Certification Conditions for Nationwide Permits Attachment 1 Below are the 401 water quality certification conditions the Texas Commission on Environmental Quality (TCEQ) added to the March 12, 2007 issuance of Nationwide Permits (NWP), as described in the Federal Register (Part II, Vol. 67, No. 10, pages 2020 - 2095). Additional information regarding these conditions, including descriptions of the best management practices (BMPs), can be obtained from the TCEQ by contacting the 401 Coordinator, MC -150, P.O. Box 13087, Austin, Texas 7871 1 -3087 or from the appropriate U.S. Army Corps of Engineers district office. I. Erosion Control Disturbed areas must be stabilized to prevent the introduction of sediment to adjacent wetlands or water bodies during wet weather conditions (erosion). At least one of the following BMPs must be maintained and remain in place until the area has been stabilized for NWPs 3, 6, 7, 12, 13, 14, 15, 17, 18, 19, 21, 22, 25, 27, 29, 30, 31, 32, 33, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, and 50. If the applicant does not choose one of the BMPs listed, an individual 401 certification is required. o Temporary Vegetation o Mulch o Interceptor Swale o Erosion Control Compost o Blankets/Matting o Sod o Diversion Dike o Mulch Filter Berms and Socks o Compost Filter Berms and Socks II. Sedimentation Control Prior to project initiation, the project area must be isolated from adjacent wetlands and water bodies by the use of BMPs to confine sediment. Dredged material shall be placed in such a manner that prevents sediment runoff into water in the state, including wetlands. Water bodies can be isolated by the use of one or more of the required BMPs identified for sedimentation control. These BMP's must be maintained and remain in place until the dredged material is stabilized. At least one of the following BMPs must be maintained and remain in place until the area has been stabilized for NWPs 3, 6, 7, 12, 13, 14, 15, 17, 18, 19, 21, 22, 25, 27, 29, 30, 31, 32, 33, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, and 50. If the applicant does not choose one of the BMPs listed, an individual 401 certification is required. o Sand Bag Berm o Silt Fence o Triangular Filter Dike o Stone Outlet Sediment Traps TCEQ -20230 Revised April 13, 2007 o Rock Berm o Hay Bale Dike o Brush Berms o Sediment Basins Page I of 3 401 Water Quality Certification Conditions for Nationwide Permits Page 2 o Erosion Control Compost o Mulch Filter Berms and Socks o Compost Filter Berms and Socks III. Post - Construction TSS Control After construction has been completed and the site is stabilized, total suspended solids (TSS) loadings shall be controlled by at least one of the following BMPs for NWPs 12, 14, 17, 18, 21, 29, 31, 36, 39, 40, 41, 42, 44, 45, 49, and 50. If the applicant does not choose one of the BMPs listed, an individual 401 certification is required. Runoff from bridge decks has been exempted from the requirement for post construction TSS controls. o Retention/Irrigation Systems o Extended Detention Basin • Vegetative Filter Strips • Grassy Swales • Erosion Control Compost • Compost Filter Berms and Socks o Constructed Wetlands o Wet Basins o Vegetation lined drainage ditches o Sand Filter Systems o Mulch Filter Berms and Socks o Sedimentation Chambers* * Only to be used when there is no space available for other approved BMPs. IV. NWP 16: Return Water from Upland Contained Disposal Areas Effluent from an upland contained disposal area shall not exceed a TSS concentration of 300 mg/L unless a site - specific TSS limit, or a site specific correlation curve for turbidity (nephelometric turbidity units (NTU)) versus (TSS) has been approved by TCEQ. V. NWP 29, 39, 40, and 42,43 The Corps will copy the TCEQ on all authorizations for impacts of greater than 300 linear feet of intermittent and ephemeral streams. VI. NWP 13 and 41 The Corps will copy the TCEQ on all authorizations for impacts greater than 500 linear feet in length of ephemeral, intermittent, perennial streams or drainage ditches. VII. NWP 36 TCEQ -20230 Revised April 13, 2007 Page 2 of 3 401 Water Quality Certification Conditions for Nationwide Permits Page 3 The Corps will copy the TCEQ on all authorizations for discharges greater than the 50 cubic yard limit or boat ramps greater than 20 feet in width. VIII. NWPs 7, 12, 14, 15, 17, 18, 19, 22, 25, 29, 30 31 32, 33 36, 37 39 40, 41, 42 43 44 45 46 These NWPs are not authorized for use in coastal dune swales in Texas. TCEQ -20230 Revised April 13, 2007 Page 3 of 3 Table 1 Reference to Nationwide Permits Best Management Practices Requirements NWP Permit Description Erosion Control Sediment Control Post Construction TSS 1 Aids to Navigation 2 Structures in Artificial Canals 3 Maintenance x x 4 Fish and Wildlife Harvesting, Enhancement and Attraction Devices and Activities 5 Scientific Measurement Devices 6 Survey Activities x x 7 Outfall Structures and Associated x x Intake Structures 8 Oil and Gas Structures on the Outer Continental Shelf 9 Structures in Fleeting and Anchorage Areas 10 Mooring Buoys 11 Temporary Recreational Structures 12 Utility Line Activities x x x 13 Bank Stabilization x x 14 Linear Transportation Projects x x x 15 U.S. Coast Guard Approved Bridges x x 16 Return Water From Upland Contained Disposal Areas x x x 17 Hydropower Projects 18 Minor Discharges x x x 19 Minor Dredging x x 20 Oil Spill Cleanup 21 Surface Coal Mining Operations x x x 22 Removal of Vessels x x 23 Approved Categorical Exclusions Revised April 2, 2007 Pagel of 3 Table 1 Reference to Nationwide Permits Best Management Practices Requirements Revised April 2, 2007 Page 2 of 3 NWP Permit Description Erosion Control Sediment Control Post Construction TSS 24 Indian Tribe or State Administered Section 404 Programs 25 Structural Discharges x x 26 [Reserved] 27 Aquatic Habitat Restoration, x x Establishment, and Enhancement Activities 28 Modifications of Existing Marinas 29 Residential Developments X X X 30 Moist Soil Management for Wildlife x x 31 Maintenance of Existing Flood x x x Control Facilities 32 Completed Enforcement Actions X X 33 Temporary Construction, Access and X X Dewatering 34 Cranberry Production Activities 35 Maintenance Dredging of Existing Basins 36 Boat Ramps X X X 37 Emergency Watershed Protection and x x Rehabilitation 38 Cleanup of Hazardous and Toxic X X Waste 39 Commercial and Institutional X X X Developments 40 Agricultural Activities X X X .41 Reshaping Existing Drainage Ditches X X X 42 Recreational Facilities X X X 43 Stormwater Management Facilities X X 44 Mining Activities x x x Revised April 2, 2007 Page 2 of 3 Table 1 Reference to Nationwide Permits Best Management Practices Requirements NWP Permit Description Erosion Control Sediment Control Post Construction TSS 45 Repair of Uplands Damaged by X X X Discrete Events 46 Discharges in Ditches X X 47 Pipeline Safety Program Designated X X Time Sensitive Inspections and Repairs 48 Existing Commercial Shellfish Aquaculture Activities 49 Coal Remining Activities X X X 50 Underground Coal Mining Activities X X X Revised April 2, 2007 Page 3 of 3