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Arbor Manors-CS091006 (2)DOWDEY, ANDERSON FAN\ & ASSOCIATES, INC. CIVIL ENGINEERS 5225 Village Creek Drive Suite 200 Plano, Texas 75093 972.931.0694 9729319538 fax MEMO FOR RECORD DAA JOB NO. 05088B 10/6/09 TO: Keith Marvin, Mike Garza — City of Coppell CC: Jeff Barrett, Larry Jackson — Weekley Homes; Dale Powerie — Construction Manager Tom Ishmeal & Brent Villhauer — Rodman Companies FROM: Matthew Alexander, P.E. RE: Arbor Manors (05088B) Coppell, Texas Per our meeting, Wednesday September 30, 2009, DAA dispatched a survey crew to site to ascertain the rim and flow line elevations of the proposed manhole constructed over the existing Coppell sanitary sewer main (Verizon Main) that will provide sanitary sewer service to the Arbor Manors subdivision. We found the rim of elevation of the subject manhole and used the tape measurements taken on Wednesday to arrive at the flow line elevations for Line "J," and the existing main at Station 0 +00. In addition, we also tied the rim elevation and the flow line for the other following manholes: 1) manhole upstream of the subject manhole on the "Verizon Main;" 2) the next two downstream manholes on the northside of Sandy Lake Road where the "Verizon Main connects; and 3) the next upstream manhole found on Line "J" at the intersection of Arbor Manors Drive and Sandy Lake. The attached exhibit provides a pictorial representation of the rim elevation and flow lines for the aforementioned manholes. Our crews found the rim elevation at Station 0 +00 to be 486.54 and the mathematical flow line for Line "J" to be at elevation 476.62 feet and the existing flow line of the existing main to be at elevation 476.29. The flow line for Line "J" at Station 0 +00 should have been 478.50, according to the approved engineering plans. The difference in flow lines for Line "J" is 1.88 feet to low. Our crews found the rim elevation of the next downstream manhole to be 485.54 and the south flow line (Verizon Line) to be 477.08. This means the existing main under Sandy Lake is flowing southward instead of northward, and the flow line of existing main at Station 0 +00 is approximately 0.79 feet below the flow line of the Verizon /Line "A" Manhole on the north side of Sandy Lake. This information provides a reasonable explanation for the issues found at the proposed manhole at Station 0 +00 and why the sewer connection to the existing sewer main could not be made. Based on this information, we have met with the contractor, construction manager, and our client and the contractor is going to reconstruct the Line "J" sewer main from station 0 +00 to 4 +87.50 in accordance with the approved construction plans; therefore the new flowline of Line R:\ Data\ 2005\ 05088 \05088B \00 \Correspondence \Memo's \05088B - 09- 10 -06- memo for record.- sanitary sewer tie -in issue City_contractocdotx DOWDEY, ANDERSON FAN\ & ASSOCIATES, INC. CIVIL ENGINEERS 5225 Village Creek Drive Suite 200 Plano, Texas 75093 972.931.0694 9729319538 fax "J" at station 0 +00 will be at an elevation of 478.50. However, the partial reconstruction of Line "J" will only correct our portion of the sewer issue. The existing main that we are connecting to has a flow line of +/- 476.29 feet which is approximately 0.79 feet below the flow line of the downstream manhole that the "Verizon Main" is connecting too. Based on our previous conversation, we have informed our clients that the City would require DAA to review and evaluate the proposed sewer flows from the Arbor Manors Addition and determine if the impacts were detrimental to the aforementioned addition or if the addition could temporarily function, from a hydraulic perspective, until the City could repair /replace that portion of the Verizon main in conjunction with the pending Sandy Lake Road improvements. As a good will gesture and in an attempt to expedite the acceptance of the subdivision, David Weekley Homes has instructed DAA to proceed with the sewer study and complete it as quickly as possible. As soon as the results of this study are complete we will forward this information to you for your review. From a timing perspective, it is our understanding, weather permitting, that the contractor will have that portion of Line "J" replaced within a week. As we mentioned at our meeting last week, Weekley Homes is currently have success with this addition and it is imperative that we have a full release of lots for sales and momentum purposes once we successfully complete our portion of work. Your assistance and support in this matter would be truly appreciated as we hope to continue our success with Arbor Manors and the contractor is anxious to complete the subdivision and begin the maintenance period. If you have any questions on this information or need any additional information from us please let us know and we respond to it promptly. Thank you. R:\ Data\ 2005\ 05088 \05088B \00 \Correspondence \Memo's \05088B - 09- 10 -06- memo for record.- sanitary sewer tie -in issue City_contractocdotx m 0 a 00 00 0 o Lo 0 a 00 00 00 o Lo 0 0 0 J U W O 0_ 0_ SSMH RIM ELEV = 486.78' FL(N) = 476.11' 42552 486.78 S FL(S) = 480.05' FL(E) = 476.13\ e Q, WV iP YY PF 4S, P �/ SSI IY (1 2f DID NOT DIP I VPF INSTRUCTIONS 4 LP SSMH 42553 / 490.25 RIM ELEV = 485.31' FL(S) = 478.09' FL(E) = 478.11' FL(W) SSMH RIM ELEV = 485.84' FL(N) = 477.59' FL(S) = 477.08' ® FL(E) = 477.87' 4 4 25 2 5, 51 485 .84 FL(W) = 477.00' SSNH 0 g UGCM ASPHALT DRIVE PROVIDES ACCESS TO GENERAL TELEPHONE COMPANY TS OF THE SOUTHWEST TRACT 42549 486.43 SSMH SSMH LID RIM ELEV = 486.43' FL(N) = 478.58' FL(S) = 479.15' SSMH RIM ELEV = 490.70' FL(N) = 481.50' 42548 490.70 SSMH SSMH RIM ELEV = 487.92' FL(E) = 480.05' FL(W) = 480.09' (110' RIGHT -OF -WAY) D , 42553 / 490.25 SSMH SSNH RIM ELEV = 490.25' FL(S) = 479.05' FL(W) = 478.95' D , a PROP .PO. ; REPLACE 114 SF OF MC'►1/%#__1 A ESVC*. DETA f W CURVE TABLE CURVE DELTA RADIUS TANGENT LENGTH CHORD C1 19'26'18' 250.00* 42.82' 84.82` N09'19'52 "E 84,41' C2 20'41'12" 250.00' 45.63' 90.26' 509'51'07 "W 89.77' C3 22'5536" 250.00' 50.70' 100.04' N79'01'40 "W 99.37' C4 20'41'12" 250.00' 45.63' 90.26' S80'08'53 "E 89.77' C5 C6 15'32'59" 10'43'19" 250.00' 218.00' 34.13' 20.46' 67.85' 40.79' N07'11 7'00"E 67.64' N83`28`45 "E 40.74' C7 2727'10' 250.00' 61.07' 119.79' N11'07'48 "W 118,64' C8 3'51'44' 518.00' 17.47' 34.92' S00'39'55 "W 34.91' : -� sf� � WARNiNGH.1 EXISTING UNDERGROUND UTILITIES FIELD VERIFY LOCATION PR IOR TO CONSTRUCTION OR EXCAVATION _ SANITARY SEWER SERVICES TYPE SIZE NO. PVC 4" 75 WATER AND SEWER GENERAL NOTES GRAPHIC SCALE 100 50 a 1 00 IN FEET 1 inch = 100 M 1. All materials and construction shall conform to the City of 15. Poly -wrap (minimum 8 mil thickness) all c Coppell Standards and Specifications and the Standards and fittings, valves, risers, tapping saddles Specifications for Public Works Construction by North Central Pipe shall be double wrapped at all Texas Council of Governments. Extend up each service at least 6 Inche 2. Contractor shall protect all public utilities in the construction 16. Retaining glands and galvanized "all thr of this project. All manholes, cleanouts, valve boxes, and provided on all bends with concrete tl fire hydrants must be adjusted to proper line and grade polywrap. by the Utility Contractor after paving, and before final acceptance. 17. Tapping sleeves: Stainless steel toppin piping with thrust blocking, solid sleev 3. The location of all existing utilities indicated on the plans iron (if not available, cost iron) for dui are taken from existing public records. The exact location thrust blocking. and elevation of all public utilities shall be determined by the contractor. It shall be the duty of the contractor to 18. No "compression" fittings will be allowed ascertain whether any additional facilities other than those lines. shown on the plans may be present. 19. All road bores shall be made using dry l 4, Contractor shall provide Engineer dimensions to all services, wet bores will be allowed. and other information to produce "os- built" plans. 20,. Bacteriological tests shall be required 5. All water and sanitary sewer lines installed under pavement mains prior to acceptance of the project. to be backfilled and compacted in 8 inch lifts to 95% bacteriological quality test is required 1 standard proctor density 0 t 2 percentage points of optimum of line. The results must be negative moisture. coliform. 6, Contractor shall be responsible for maintaining trench safety 21. Fire hydrants to be located three (3) feel requirements in accordance with City Standards, Texas State and centered on lot lines or at curb return Law and O.S.H,A. Standards, shall place blue fire -lite reflector in c closest. to fire hydrant. 7. Water mains to be AWWA Class 200, DR 14 PVC (blue in color). 22. Fire hydrant connections to mains s 8t Water services shall be located 2' from alternating lot lines Provide flat flange on in - line tee; connE of each lot and shall be a minimum of 1" type K capper. resilient wedge gate valve. Provide rel Each service shall be provided with two in -line nylon ball MJ connections at hydrant, cutoff valves equipped with lock wings and contained inside the meter box. Residential services shall have a 57'8" diameter yoke and shall be equipped with a dual check 23. Fire hydrants to be painted per City of component (as part of the yoke) and shall be of materials approved by the City (see City of Coppell Standard 24. All sanitary sewer pipe shall be SDR 35 Construction Details), All other water services shall be (green in colon. equipped with a separate double check back- siphonage device 25, All sanitary sewer services shall be 4- in a separate box meeting the specifications of the City of located at the lot centerline. Service cl Coppell. All tapping saddles and connection nipples to water Coppell Details, yoke shall be bronze, Service to each lot shall have a maximum cover of 20 inches. Water service lines shall not be spliced under existing or proposed streets or paved areas, 26. Contractor shall provide 2 -6" x 2' - pad (3000 PSI 0 28 days) for valve stack 9. All water mains shall have a minimum cover of 42 inches below cleanouts falling outside of paved areas, block out provided in paved area, Mc finish grade or as required to clear other utilities. Terra- paved area shall have a 4' X 4' block c Tape required one (1) foot above water main. 10. When installing water mains at sanitary sewer crossings, no 27. Sanitary sewer shall be subjected to leakage test prior to acceptance. joint of water main shall be within (9) feet of the centerline of the sanitary sewer pipe. 28. Contractor will be required to provide 11. Water mains shall be tested and disinfected in accordance Sanitary Sewer lines prior to acceptance test with "As- built" drawings at contra with AWWA C601. 12. Contractor shall provide adequate concrete thrust block and 29. All 4" Sanitary Sewer services shall ha` (foot) except as shown on plans and max retainer glands at all bends and deflections greater than 10 cover at the property line. The 4" S degrees in mains and hydrant assemblies. connection for each lateral shall be encc 13. A minimum clearance of 24 inches shall be provided between City of Coppell Standard Constructi contractor to paint and "S" on curb (aft water mains and storm sewer inlets. all sewer services. All lateral to have c 14. Refer to City of Coppell Standard Details for bedding requirements. line. 30. All manholes shall be equipped with a m chimney seal. NOTES; R R WATER SERVICES :e EITHER SiDE OF ALTERNATE 2' LOT LINES. : 7.5' R OW 8 WATER ROW SAN. SEW. SERVICE IN CENTER OF LOT C_ R R TYPICAL LOT SERVICE LOCATION THESE CONSTRUCTION PLANS WERE PREPARED UNDER THE RESPONSIBLE SUPERVISION OF DANIEL L. HEISCHMAN LUNSED PR F OSIONAL ENGINEER NO. 93762. � . " :•• "'�L'Cwt�rr °: ,mod - Prop. San. Sewer ----0 Prop. Manhole -40 Prop. Clean -out ---� San. Sewer Flow Din -- - - Ex. San. Sewer - - Ex. Manhole Prop. Water Blow -off Valve Prop. Fire Hydrant Ex. Water Ex. Fire Hydrant 4 ry r11. I)C~11NF1(_ AN1 X. w" nh rr cr v��nc�rr s.,.. x. 1. ALL MEDIANS AND COMMON AREAS WILL BE MAINTAINED B1i THE HOME OWNERS ASSOCIA11C {HOA }. LEGEND 1+00 2+00 3+00 4+00 u+uu 1 +uu Z+uu D_t_uu i LIJ C + 0 ZO z 4 ox Lo _1NE _4 I E XI T. 0 PR DP. R P OF CL vi v It F +Iz z 1 51 c T 7 r 77 - LT, 4 '51 7t f . . ... .... E - w - CE - PIVIr IST. C ROIJNO 1 10001'" C -W - 7 PRI P�_ UR 1910 1 87 .Owl 7— - J T445 I 505 T 0— to 41 ioo T DO M I ! 0 %..A to 1 0 00- d )D 15 CIINC. LIN. FT, N G. r I L -4— xr- G L T 0 CN N cl� co co Lo to 00 L _7 u- LL_ — T — i 7 --- --- 1" + oq - HOP I + _J_ 00 _7 JV to 41 _i­ -j— 1 i-� ff)- 8 LAJ ��J- 0 -A- Z Aj- — U � N Lu _J Ln - J 515 03 1 5 500 4 -- IT -J- + rll� c N ------ - ---- i til 6 co 95 Vtt J__ F_ PIRO CURB-, F 490' ADE 7 4-- 7 5'c %6 40% E�Sl Ac _G _P11'E ?Ot WE _J_ ---- — -- 4,95 1 p)tCl 0, 0. 495 00 - -- -- ----- p p �411 7 --A _0 Z-1- __T 00 an I 00 475 1 1 U- 4L - o) 0) 0) 0) 7 co 10 00 Do 4M 0 0 00 n 00 05 op 00 op 0 L Go 00 T CID (o 00 _i4�_4_ ui _j 001 U- 00 u- 00 00 _4 " 100 00 00 Go 00 00 00 T -------- SANITARY SEWER P1 ARBOR MANOF _4_ CITY OF COWELL LLLI 1 1 1 1 DALLAS COUNTY, TEXAS nnWni:V AMn1:QCZnW 9, d OF