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NDCFCD 2011 status review Northwest Dallas County Flood Control District a us eview 4;" Northwest Dallas County �� t , s Flood Control District * _ = 1 BRIAN ■ J. L j in , i t � ,3 o, •89363.:x The City of Coppell � 1 %, S S i * * * ** EN Dallas County, Texas ‘'.:� �p a ,' 4. g h .. ze ° s ' z .: an s., *s mow! , .Y $ � NDMCE Project # 87 -12 -150.5 October 2011 NATHAN D. MAIER 1\ _1 1 V CONSULTING ENGINEERS, INC. Texas Reg. No. F -356 Table of Contents Section Page I. EXECUTIVE SUMMARY 2 II. SCOPE OF SERVICES 2 III. LIMITATION 2 IV. OBSERVATIONS 2 A. Sumps 2 B. Box Culverts Under Riverchase Drive 14 C. Glory Holes 14 D. Spillways 16 E. Outfall to the Elm Fork of the Trinity River 21 F. General Observations 23 V. RECOMMENDATIONS 25 Appendix A Facility and Maintenance Summary 27 Appendix B Site Map 30 Appendix C Projected Maintenance, Engineering and NPDES /TPDES Costs 32 1 I. EXECUTIVE SUMMARY Nathan D. Maier Consulting Engineers, Inc. (NDM) was retained by the Northwest Dallas County Flood Control District (District) to perform a status review of the District's facilities and structures. The District is generally located in and around the Riverchase Golf Course in the City of Coppell, Texas (see Appendix B "Site Map "). In general, all of the District's facilities are functioning properly and are in good condition. NDM visually reviewed the status of all above ground facilities within the District (intake structure, spillway structures, glory hole intakes, sump banks, swales and outfall structure). Observation of the performance of below grade structures was noted, but the facilities below grade (box culverts, headwalls and storm sewer piping between sumps) were not visually reviewed for this report because they are either submerged or buried and are not accessible. Silt was previously probed in Sumps 2, 9, 10, 11 and 14 to evaluate sedimentation build -up rates since those sumps and associated box culverts were cleaned in 2004 through 2006. Negligible sediment accumulation was noted and therefore silt was not probed for this review. Silt will be probed periodically for future reviews. II. SCOPE OF SERVICES NDM is providing engineering services to the District. These services include: 1. Performing a site reconnaissance of the District's structures and facilities. 2. Preparing a report identifying the condition of the District's structures and facilities. 3. Updating the 5 year maintenance schedule. 4. Attending a board meeting to answer any questions the District has concerning this report. III. LIMITATION This report was prepared for the District. All information within this report is confidential and may not be reproduced or conveyed in any fashion without the expressed written consent of the District, and NDM. This report was prepared using generally accepted engineering practices and no other warranty is expressed or implied. IV. OBSERVATIONS The following are photographs and comments from NDM's observations. Refer to Appendix B, Site Map, for locations of photographs and facilities described. A. Sumps Sumps determined to have an impact on the hydraulic performance of the District's facilities have had sediment removed. Sediment was removed from Sump 11 in 2004. Sediment was removed from Sumps 9 and 10 in 2006. Work to remove sediment from Sumps 2 and 14 was completed in 2007. 2 Although some sediment accumulation has previously been noted in all of the recently dredged sumps, sediment levels are minor and pose no concern at this time. Some minor erosion was noted along the banks of the sumps but does not appear to be a significant contributor to sediment accumulation at this time. Erosion along the banks of sumps was evident at headwalls outfalling into sumps as well as at the intake structure in Sump 3A. Vegetation growth prevented observation of these areas in detail for this review, but no signs were evident that this condition has worsened. Storm water levels were very high in 2007. Minor slope failures were noted along the banks of Sump 3A in the 2007 report. Vegetation growth prevented observation of these areas in detail for this review, but no signs were evident that this condition has worsened. A sinkhole over the box culvert outfalling into Sump 11 was noted. It was also noted in our reports 2006, 2007, 2008, 2009 and 2010. It did not appear to grow in size since the last observation, but is likely the result of some type of void in the box culvert allowing the infiltration of soil and water. Aquatic vegetation was noted in Sump 9. Previously noted cart path bridge erosion has been repaired by Riverchase Golf Course. Previously noted debris at the outfall of the box culvert in Sump 11 was removed as a part of the 2010 Miscellaneous Repairs project. Previously noted sediment and vegetation at the intake for the box culvert under MacArthur Boulevard outfalling into Sump 11 has been addressed. Sediment accumulation and vegetation growth were very minor at the time of this review. 3 . gy p: . f «nom 1Y k s. " � ' `a y g • $k � gktS k •�2 Y 4 � 1 P ' @ ' � a d' 1K ; W •R � 3 ,,,. i k yep \ � s 4 '7x -' " ?, i t z t.' ' . ‘� - - � � a �sn � 5 ,� ` � +„��. � x �a s sex a � � � . X t .. . , �� � sue {: - � ', z ■ Photograph 1 Sloughing along Bank of Sump lA 1 !ty- - r " ' q Q. Fm ' ,� .A" C . �+ f 4 —" ., A" #yam , ,v ' t iF w,a . g &a w" e # $ 4 L r ;� . •as � ` , ,, d „' ��.' Photograph 2 Sloughing along East and South Banks of Sump lA 4 4 - a 4. t; ,‘„ z, ,,-, -„, , , "" .- .'%■ - , !* « Y < 1 „414 - }n .....4t:d-z * WL .7?),!,- 4.,,..,--72'''''',ffi".° -,:g:4";-"M., '7"-- - 7.," ° T " / 44w - 444 444 . i.__.‘. 4 4 4.. - 4. # A X ke ' ' r f # Y r -' wF : � S ,,,y N yw y w� R +k % e P Photograph 3 Sloughing along West Bank of Sump 2A d i p : . f 'a �, - ' a $ y x s Wi q t+ t a s w"�- s ro'�'i ? 0' ' ,t Photograph 4 Sloughing along Northwest Corner of Sump 2A 5 1 ..... .. ..,.. .' sue. 4 444 4 , : :::11k '''': ; , : 47L 1 4 ''' .i ' , . -„-"' s w !„ :' , , 4.. ' ■ z< f Photograph 5 Area of Previously Noted Erosion and Slope Failure South Bank of Sump 3A V v V v AA \ v \ V Av \� v \ \ �� \ V AA v A Vv - - bro Photograph 6 Area of Previously Noted Erosion and Slope Failure South Bank of Sump 3A 6 ... k ,ex . : ° ,, » (If, x ; ya�? p 4 ,gg a Photograph 7 New Gabion Mattress on East Bank of Sump 3A u* ; A �O � a a .. ia „- . -.. r #5 Photograph 8 Sloughing along South Bank of Sump 9 7 a ° ° T " �` .. : _ 'mss,: '^ h.�. i‘ , . s \ t -'17,1:' t ' < r . ga." Photograph 9 Sloughing along South Bank of Sump 10 y x. r Photograph 10 Sloughing along East Bank of Sump 18 8 jw. .. , ., , . ... ,,,.,,,_ . , - ,., , „... ,....., ..,, ,,._._ ,.. , , ,,,,.„, ..... ,..., . , , , . , ,.., ,. :„ ,......,,,,,...,„..„. r ---. K -,..,itt,,,j .r--k -,..!),/ , : :4-'1,,r.,#' .,, - „=-.._jj:'7'.. - - ,..,-:-1.;:--. , -,„ ,.. , ., '-',','.'s'J'' ‘' � 'ar ," a .;, ��°'" t q � "� •qr,d " � .+>. m4 4 N x.- u�' ' '''''' , ii « x P hotograph Box Culvert In for Culvert un der MacA Blvd ta ; » � r y � S� 6 , '?;."'4"7.,. , ` �' � �,> � � � y ,k y, Ky uu Y . ww+ * , { .'ry ° �{ A l b . "A. x & y��'"'" �" a �''"'„ r; 40''''":' ` " Si, "� ? e rdC.4 S 3 :. \ s. . i r e f T '':',"..s4 y t <��� .� r ,�, yi n r " � ��� � > � 1 '' � t x „ .5a ''"- . N 5 .t 4 -•r '° Y i +..' r. _ � � � �e . ����� # �° y : *„yk $ 9^ � ?u � f fie, � s � q # „ t, ��a �„ ,4 w`G ii dF' %�, .., u ,� "",, ,,�.# Photograph 12 Sin ov Box Culv that Outfalls i nto Sump 11 9 ��_ . ,, a ,, S � .r r -...w. r t 'ii '..„1.' ,, � � �� \. s ,. .:: v :: i '1 c :r te ,- * : x 7=,, ' -K t . , ",;',A,';'' ;" fe fie " . � i .. :;":,?'!.4f; � le :, -r W " s�. �` ,., '+ t te u + � �9w � ,,z..--,'„1-k;.-4',1.-z.;,,::r.,..Y.,.-4,4,401'7.,*,-4.k-'..',.vitii; .''''. - -.,. ' ,, -:,. ---- - -- - --,„.4:° , :4'1,A44!: ' 7 „,e' i;-"iifi,7;1;1 ,,°. ' I V, 114 ..., - *. 4 , ,,,,,!'' 5 '4,....1"...trkt,,141,%'x' 4 ''-,'.','!"` .. ' - Al" ,,.! . ' ',. ' ft' 77 ;tifl''''''''ij'4. "-- 4';? '"':' ' '''' 'i ' ' -`',0 *.4 t7' 1' ' . Lilt ' :'; : k.' , '' .4 4.:r,,.. 1 ' ' ' ' t k '' ' :: ' ' ‘,'","." ''' ,'''' .„ , ,, Y , 7.1.g .4^ , ..4 0 .9.,....!.A.',,,,ri: A ..4 : ,-..- - -,. , 7.1t , .,, ,,---,--.,--,, - --",-, :, .. ,,...,.- - - .',- - .., ,,,, Photograph 13 Box Culvert Outfall in Sump 11 r Photograph 14 Sump 11 10 , t4.._-,....: , „ ., .. .:-..,;,- ,, ,, ,„ _1,,.., ' 44 " . ; 0« `*• a ' ce ,: a , R , + , ,' . as g w ws rp , ,. "Ai' '+ - Y _ „ , 4 fin'` +x; "� f 1 * „ 2 "K y , `' ' i t s ,�.�: `R t , '.:$" . £ • 4, " , � *esa .C:6 ''',404-4i-4,i7.-,..:1,. ,ski ? . ° C,w3,'.� ; „ . X 4 ° t `t .. '' �,n :rte £jR� r ws„ ,„ ...,,r ,. .. ..# r.. 2 r Photograph 15 Erosion at RCP Headwall in Sump 11 awe ° ,� a� � . s x i k r a-' . w s LL Photograph 16 Aquatic Vegetation in Sump 9 11 ' j . x ^x M x 1 !f 1 y `d� "` Y " . Photograph 17 Sloughing on Bank at Northeast Corner of Sump 13 y ;O fi ter to 111E - e t ,.�.d * s , rg �, : " ...-, EHFZWO`W, w w • 9 • T P j f y( ( i , I ' Photograph 18 Sump 14 12 y a�f ' ;ms x � l ;' .' % , .; b4 " , . 7„,, s4x z a' � .tip;-' r t r y ' *. w , £ a , '. i r#`rs' y t , , Ate`` ` R r � ' §t'' r' �,i ,J)*" . „ .x '" '27" ..a Y. ..r .+:yak «ax t q t r , t� M <b r s ;akQ ,r �." §_',�a . Photogra 19 Sloughing at Northeast Corner of Sump 14 Awr ,5" . rai ,r � ,. ` ` , rrroom ,‘,-----,:,',°' w ».nw ,, m awv ror , n „.. ...__,, let.. ^ '.�. > t ev � � tf 1,4 " �f^ x wrc 441-4y, q r., i �� ,/,‘..44...4.P:.f:4 'il'''' ' .-. 0 . ,.°"` doe , !....T r.”. , :,,„, 44„, 4,,,.,,,,‘ f,,,,,,,1444,,,,,441,,,10,,,,,,„0,4,,,,k...., Photograph Erosion at Southeast Corner 20 of Sump 2 13 B. Box Culverts Under Riverchase Drive Both the 5 -8x4 box culverts (Line A, between Sumps 2 and 14) and the 4 -8x4 box culverts (Line B, between Sumps 9 and 10) had silt accumulation removed in 2005 -2006. Since the box culverts are submerged, no additional observations were made as to the overall condition of the structures. Sediment accumulations along the intakes and outfalls of the box culverts were probed previously during surveys of sediment accumulation in the adjacent sumps. Based on that information, sediment accumulation in the box culverts does not appear to be a concern at this time. C. Glory Holes Visible portions of all three Glory Holes appear to be in generally good condition. Vegetation and debris blocking the openings in Sumps 2, 13 and 18 were removed as a part of the 2010 Miscellaneous Repairs project. P m 1 , k + -,tom * 43 ,,. � t \ : < � Photograph 21 Glory Hole at Sump 2 14 it *''''"';`,' -'''' t '''' 4 `',, - `,"'-'-. - "„ :„:, :‘,. ilf,Atil i ",\,,, 4,„ •' " ,4 , - ■ i v s `�' ' �, „, ' ' ° yam v i a 4?-1,, r . , ` t r. y 4 c 4 .k � ' ' 1, t; ' � — .as s A. s ' �3 Y t ry' � ' sy v h ' ' ' ,' ` r te, , s � , ` .k. c A. 1'l. a 6� ,�� a a pe d ., . � i � l i ... Y y "H _ 1 4 t�; — £ t . Photograph 22 Glory Hole at Sump 13 t i ! '',: , s ' 'r ,P'' -.�c 'o e. to b F� g ,' „» �+ a <b ` p, ^ V• .Y%�` , a �� '`. c' cc Y v . y ' ,� # ".. 6* Rya s a,vt . '11. 3t a s k. = fi - ".e t' �, y , Photograph 23 Glory Hole at Sump 18 15 D. Spillways All spillway structures were replaced in 2002 and 2004. No concerns were noted during this observation and the structures appear to be in good condition. Golf course maintenance has been performed at Spillways 5 and 6. The condition is improved at both locations. Vegetation was noted growing in close proximity to Spillways 1, 2, 3, 5 and 6. ° .4 - moo\ f e w' . �� S w a. i w. � -, F � z,.�. �` ff* r `"'"M x ,w y � =*` - e & , Ys a • 2 s -:":.,!1`,.,,,Y",,??, t ee a# , Y? t e? a � " . * h d °N"� - �" Photograph 24 Gabion Spillway 1 at Sum 1A 16 Photograph 27 Gabion Spillway 3 at Sump 13 Photograph 28 Gabion Spillway 4 at Sump 3A 18 a wit, sat x • 4A I . r r '°"" ,° 4 ; }s. '�„ t s ANY Photograph 29 Gabion Spillway 5 at Sump 10 ' " ,.� 113. �$�., ���1 � � • .. ' a"" .o;ai r §a � gggg dl xa M.n� ix �. .i. ' a4tx "a 8a Photograph 30 Low Area behind Gabion Spillway 5 at Sump 10 19 4 e r + . - . ,'fin ,+r' fi .:,,,'''''.1,14A."'"4.''''.' xr a ,• ��.. rt �- „ a Photograph 31 Gabion Spillway 6 at S 18 g , , ary -,,,E-:,::.,,,,;-4-,':'-',;:'-'---7;::' 44 ,, � N., S k x+. v 4-,.''' ' '^r0--,.,,,,;', , '1'.- y a • v Photograph 32 Rough Grade Behind Gabion Spillway 6 at Sump 18 20 E. Out fall to the Elm Fork of the Trinity River The damaged gabion mattress at the inlet structure was replaced as a part of the 2010 Miscellaneous Repairs project. Areas of erosion were repaired. The visible portions of the inlet structure appear to be in also generally goo condition. The outfall structure shows signs of some minor damage , but continues to perform its intended function. Minor cracking is evident in the headwall structure. Some erosion was previously observed at the bottom of the spillway as it enters the river, however the bottom of the structure was submerged at the time of the review. The eroded area was not visible, but there were no visible signs of damage to the structure. The noted issues appear to be unchanged from the 2010 review. \D` ^�``' YJJ: JarYN � AteY+:�a. 0. P az �1° F� a ��aJ � a � 4 � �V v „ !;:. , 0',.11 - 1 4 °\ t ''' ti era q e� \ k aY� l�6 . �" .” � n pJ , � ; � ae ..�° ; h Y �L J ��j ; tM � 4 a Y- ` � �Q�B t ter. � aj: Y i C 9 j � e C e n x: e gn. Photograph 33 Gabion Mattress Apron and Inlet Structure at Sump 3A 21 ' '.. , z,, ,, ,,,, i.., '''. „„ , ' , ,, '' „ ,„' " , T; Atk, ,,,, .,. _ - ' t 0440v .4.‘kkqr a ,- Ph otograph 3 4 Gabion Mattress Apron a Inlet for Out fall St at Sump 3A ,. - _ . _.,. : � • '.' "..w. M �� , an .. �s't' w. ' ��w ,...i,,ie , - i a r ''''' ''' '''':/"Ht.:1' 111:411/44040: 1*41:'.1" lit'ir:,..'....." , '4'11111'S'' Nielt Vtg itoittlitoit y4 Photo graph lm For 35 of the Trinity River Outfall Structure at 22 s ' � t: a +t "s : P !t 1 ' 'd" .,4 a r„ s; + ♦ _ :' ' ' ' -- -, * 77 : ' ' 4 ` ,, fi ' ''t O.4 * " 'a .: "` a� ," ► a". , 7 : : 1 ; ,' ' 42 ` ,t t - w "Ito .` : - : �, ., ,,, w w, Pa: Photograph 36 Outfall Structure at the Elm Fork of the Trinity River F. General Observations Stockpiled wood mulch and sand have been observed previously in the golf course parking lot. These materials can wash into the storm sewer system if not contained. No material stockpiles as noted in previous reports were observed at the time of this review. A previous problem with standing water in the TXU Right of Way adjacent to the District's facilities has been reported. At the time of our observations, water levels were elevated in that area. Coordination with the City of Coppell to address this issue is ongoing. Vegetation along the banks of the Sumps did not appear to have been maintained for some time in many areas. While vegetation may have an adverse impact on the District's structures, the vegetation may help to deter bank erosion that has been noted. Standing water between Sumps 8 and 10 was noted in the previous report. No water was observed at the time of this review. 23 ;Lt r . .k,''' , (4 , ,i ' if'' '',"'"':*:' r116 ''..,. . , ‘ ,0 kW. - .*, ‘, . ,: k.14 - ',4.0 \ '' ''' :'; ''' :; , : ','' '' ' ;', 1'' ' ' ' '.1 , ' ; ' '.. ' '', - ;: .' Vi -,';',,,'-','" r''77,-Z-"7'47!7',.!;;'ir?:rlyi'gt*i:;'';';k,:45';-.'Z;7'4;t,147i''L't;iti4'ti*L';'r.,';I;-;',*i';7;.,'\,'',C‘k:,;,ih.,:t'''i.t':,,; , 0 ,, ', , s4 . 0. . ':i::. ,,,,,,,,,,- [ I - ._ Al ! T • • • • Photograph 37 Vegetation and Standing Water in TXU ROW behind Gabion Spillway 3 A a Oti tOtig .: 41 , N. 1 :X\ \ \ .P . '.4 4 k,\Zk\ Att .1 ' ...:.'. ' '. . .'..'- . ,..v.'" . ' -.'' :'.'.'NT!';Ikt=',''',.'f.i..'''''.?;;,'";44*.4r.'5%.11.1V,%;41'i 0 ; ,‘",.;,,,,,\,‘ \ ,C \c‘i0 't, , ' 't:t, '',''.',,, - , , : . , ,, , , , , ,,,,_ , ,,,,,,,, ,,,, , ,,,,,,, 4 7a . ltv. .,, q + E '/ Y. N d" ,, {: fi e . j t d Photograph 38 Vegetation and Standing Water in TXU ROW behind Gabion Spillway 3 24 c4 = ` q ' . **, ' 44;0 ,„ .r, :rat ',,-Ak ' A r " .' .:.- bS' r. n ..i 1 „ . - �`" .et s � %s ' : i f / f'" ` gy .'" ai . '" ,g rc aa,� : f '44:4, ' u. x ^x 7�P _t , ... � � , t , .1. :., "'+Ma " p ! .`" Y, n k w� y a 'F " ( ,� f f os W 'r ,. 1 s - W " r t r t.E fe 1 ' tit ' , ! E% ,,, , c s ,, ; k. _: 1" rx : :`!;1 4 1: 1" r , 3rtt� r A Photograph 39 Vegetation Typical along Banks of Sumps V. RECOMMENDATIONS In general, the District's facilities are in good condition. However both maintenance and monitoring are advisable. 1. Sump Bank Maintenance: The District should contact Riverchase Golf Course again regarding the maintenance of the banks of all sumps within the District in order to address erosion and sloughing which will likely contribute to sedimentation of District facilities; however this does not appear to have a great impact at this time. It is our understanding that the golf course is responsible for the maintenance of the slopes and sump edges. In addition, vegetation growth along the sump banks obstructs the view of the slope conditions. Riverchase Golf Course was contacted in previous years to mow sump banks prior to the District's annual reviews. Course management personnel expressed a desire to assist the District, but reported they received a corporate directive not to prioritize maintenance of the sump banks. 2. Sinkhole over City Box Culvert west of MacArthur: The District should notify the City of Coppell again as a courtesy regarding the sinkhole over the box culvert upstream of Sump 11. The void is located west of the commercial development west of MacArthur Boulevard. This void has been noted previously and has also been repaired previously by the City. No significant visible difference in the void was visible in comparing photographs of the current condition against photographs from a year ago. 25 3. TXU ROW: This area is within the District boundary but is not owned by the District. It is our understanding that the Riverchase Owners Association, Oncor and the City are ultimately responsible for maintenance of this area, however, NDM, at the request of the District, has submitted grading plans to the City of Coppell that could be used to address the situation. The City of Coppell has indicated they are interested in participating in possible construction to address the standing water. They further indicated an interest in expanding the proposed grading area. NDM participated in a meeting at the City of Coppell with Oncor and owners of the affected property earlier this year. The City has proposed a trail project that will include improvements to the affected property. NDM has submitted an engineering services proposal to the City to perform an alignment study for the trail project and is awaiting the City's response. 4. Vegetation Growing Near District Structures: Vegetation growing near District structures should be removed. 5. Severe Drought Conditions: It should be noted that this review was performed during severe drought conditions. These conditions may have impacted previous observations such as standing water behind gabion Spillways 5 and 6. It may be prudent to perform an additional review of specific areas once drought conditions have ended. 6. Aquatic Vegetation in Sump 9: Aquatic vegetation should be removed. 26 APPENDIX A FACILITY AND MAINTENANCE SUMMARY 27 0 O >• a) 0 0 = I: n c0 • c0 O T C0 T N T y (` 0 0 ) 0 0 0 0 0 C7 o C7 o C7 0 0 0 0 0 o f o -6 N N N N N N N N O O O O o O 0 0 O_ r C 0 O C 0 0 o •:1' C o -. N N N N N , O N _ 0 - N '- '- ' - O O O - C C C C C O N C 0 0 .0 o 0 0 N N N a) N a) aaaa a a c a c o r > > > O > > C N C 0 C N 0 0 0 0 G) 0)-- 0 ' 0 O O a O O 0 0 0 U U U (a U C 0 O O 0 a 0 - 0 - N ro b t0 a7 a) ' O t0 N • 2 0 0 0 a o O 0 "o nano. 0n0u a o E N ro 0 N 0 G) 0 0 G) 2 0) 0 2 'C a C C N C C C w o ti o) w O G) 0 0 0 0 a N 0 a) 0 ,,. 0 0 y 0 0 0 .c c C C - c co 7 O 7= 7 i 0 0 E E. 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U U > ; mo O ` p p N ,c2 E U U O i CZ m m a d o o CL m a s • m N N . a) C N .N- n O_ O O U CC O j j ) U m a) c) m o U - o E E f u) w a) i a) Ili 3 a c,."2 m a) a s >> � U . d a) 6o c r oc cc 0 a) N N f 0 x0 u) U a) C C U U C C aL p • c as ni a) a) co N L w _o C c n E E C C a) a) O 'O R1 a° '- E a a °) CD w y m 0 0 O C O a) a) C C C O an c0 C7'� �(o(oU) td c0 �� 00N • o I N 2E co U) u') 2E 2E O O i p c0 CO_ E' g0 8888 0 0 0 0 E m N 0 C1.' N Z N N N N Z Z N N T,- 69 c 5 a o d 0 0 S) C -0 l] C . U U C a' O c F.2 O U 0 N co 7 L() a7 Is a0 0) O r o 0 = U 0 0 0 0 0 0 0 0 C d Q Y N 0 N N N N N 0 0 N 1— o p W U U U o °'= :j 0 U V . APPENDIX B SITE MAP 30 I 4 O / l — — il w 1 #4, ,, 41 A 4� (5)* 1 n Q' , ► I �Se 8 j ` ;, _ ,�11 1 Q . GABION SPILLWAY fl . U 1 /// isy \ p' (Replaced in 2004) BRA CART GLORY HOLE I el - - - - - -I I - - I . suMP X14 — T , < < ' SWALE � T � 1 "/ii/ I. �� �° . �� 1 ' _ ® r� Q Q gw e 4 d CULVERTS ) \ GLORY HOLE I ` ' ' �' I 'i N // � 1 Repl W oa A . Y d 20 I � i ., ° ► ©� ; _ • Rhumbas, Golf Course hole number GABON . \ \ LLWAY V !Replaced in 2002) �\ ' ',0% , 1 A7UC) Location, direction and number of photograph 1 t0 Property Line a 300 150 0 300 500 — — — — • GOLF COURSE & GOLF COURSE FACILITIES 6 SCALE FEET � . NOT TO SCALE FOR REFERENCE ONLY \ 1 ` -- — / 0 1 $PL /� CAR 1 !' GABICN V / \ 1 r 1 (Replaced In 2002) M 1n #I0 4) \ FACILITY se 2- 00' RCPI ii I U\ 2 - 42 PCP (Dndg d� In 2004) V (Rips 2002) \ — I � � ►�� , ► sTRUCTURE SPILLWAY fill — ® Vic; / ,` `o , ; 2 j _ / . . �- `O STRUCTURE = c OM ' GABION SPILLWAY �4 l T 4 - 2 / , :.r — i� _ — BOX CULVERTS SWALE WWI (Replaced In 4004) N (leaned h 2005) PVC CULVERTS 2 -7X5 GLORY HOLE 0 CHAARI f BOX CULVERTS SWALE wlm PVC � S` PIPE CULVERTS -- - — — BM V1 I (Cleaned In 2004) �l cut h top Of curb on east side O _ — 1 1 Rim- CAae. Drlse so't south of centerline — 1 17 of tnteresotion of Westchester Dr. 7 I Elev. ■ 453.00 . 1 _ side _ — 1 o Dr. north of Stonecreet t from _ _ pr.w� Note: 2 _--� --� L�4 `rw rrf -� � � for Rlwrdicea r Structures from .n Ow. — 44t... Ksy Map tho draetp hom the Den DrainaStructures t1 — —�_ a .T LINE R0 — _= RARRQAD — — — _ _— — a.. u —___________ .......d > C1 —_ — -J Q -_______ p SITE MAP APPENDIX B _ 5 sheet no. NATHAN r MAI ER NORTHWEST DALLAS COUNTY ° ~ FLOOD CONTROL DISTRICT rn CONS ENGINEERS, INC. NORTHWEST DALLAS COUNTY THE ITY OF COPPELL n a — \D FLOOD CONTROL DISTRICT DALLAS COUNTY, TEXAS W v Ni Two Northpark / 8080 Park Lane / Suite 600 design drawn scale date file name job number T, Dallas, Texas 75231 / (214) 739 -4741 NDM AS SHOWN 9/11 �Ot 1 87150.S APPENDIX C PROJECTED MAINTENANCE, ENGINEERING AND NPDES /TPDES COSTS 32 0 0 0 0 0 0 0 o o 0 0 c O M O r 0 co O M O W co of N N CO V) V) to V) EA 0 u o To f6 (6 O O O 0 O 1- 1- 1 1 H • a a N N U) N 4) C C c c c a E 1— U U 0 0 0 N M sr to Co C O O O O O N N N N N 3 O O O O O E N M 7 Lo 0 E - O r r o o N N N N N 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O O 0 O 0 - 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L0 0 L0 0 00 0 (0 M 0 0 0 0 N 0 L0 r ( o LO O 0 11. . I� O) V• EO CO M) Ni CO N ,- CO N N M V) V) V) V) V) E A V) V) V) V) V) V) E „, EA V) V) V) w _ N I o w L _ a w 2. 0 Q _ v O w co � zi E o o O O o O o 0 0 o O o o O o O o O O O o _ V> O O O V) 0 O 0 V) O 0 O V) 0 O O V) O O O r L . (0 O CO L0 0 (0 (0 0 LC) L.0 0 10 LE) 0 00 0 s- XI o D 0 ' m O 0 e (1) NC ti' Cl) t E N 0 7 z C N .N .. EU j 3 . . ^ ET C c0 c co cu ca U) U o N N 3 N N N N N V a.) a) Ct N N L w N -- > a ED > a) EU O ca a) a) m a Q' Ce V) Q' 1 V) Q' Et V) 2 W V) W W V) w C , N 7 W N EA W N N W N N W a) N W A w E „a 8 d Y N d CO N d CO y d m N d w (h m m m m m w o0 v p a v p w c� d p = v m 0 0 w } ID En C w O c d N o c N O c N d o c y 0 o W e • Q: z F Q f z H Q 2 z F Q z H Q 2 z H u) a 3 Eu 10 0 Eu a 13 z . a i»: C 0 E 0) EU N M co C a 0 0 0 0 o a`) woo N N N N N C W 0 N Eh y u) O o O O O •. N N N N N W x 1 - ,,, _„4 , ....w" . ',..,'"'....:,. .-.' ,, ,..t.i:': } a " & „ ark �� 8080 �� �/ N A THA N D. MAIER Par DaIIas,TX i 75231 I V CONSULTING ENGINEERS, INC. (P) 214.739.4741 (F) 214.739.5961