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Home My WebLink About20112640.tiff • Exhibit N Drainage Report See the attached drainage maps and drainage report. • • 2011-2640 • DRAINAGE REPORT FOR LA SALLE GAS PLANT do --P Midstream. DCP Midstream, LP 370 17th Street Denver, CO 80202 June 2011 • CI ENERCON Excellence—Every project Every day. e JIII''c?o PD iii Li - 0 (tEh�F� S Submitted By: --ety :✓ c Anubhav Gaur - Technical Specialist .zr p : d ��: ?emu SS/ONAI E��G�iiO P (� � 2uII Reviewed By: hhhk^ Professional Engineer: Pat Brunette, P.E. Registration Number: 39164 State: CO Suraj Balan - Project Engineer • d c DRAINAGE REPORT LA SALLE GAS PLANT • Midstream. TABLE OF CONTENTS 1.0 Purpose 2.0 Site location 3.0 Site Layout 4.0 Methodology 5.0 Watershed Delineation 6.0 Design Inputs 7.0 Calculation 8.0 References Appendices: Appendix A HydroCAD Existing Condition Appendix B HydroCAD Proposed Condition • Appendix C FlowMaster Analysis Attachments: Attachment A: Existing Onsite Basin Map Attachment B: Proposed Onsite Basin Map Attachment C: Grading Plan Attachment D: Erosion Control Plan Attachment E: Erosion Control Details • CI ENERCON E R C O N (405) 722-7693 2 dcp DRAINAGE REPORT LA SALLE GAS PLANT Midstream. • 1.0 Purpose The purpose of this Drainage Report (Report) is to establish overall storm water drainage patterns, constraints and details for a proposed gas plant (site). It includes an analysis of onsite and offsite hydrology, and calculations to substantiate onsite and offsite hydraulic design. 2.0 Site Location The site is located on an approximately 160-acre (ac) parcel of vacant land located in the southeast quarter of Section 31, Township 5 North, Range 64 West, approximately six (6) miles east of the town of La Salle, Colorado and three (3) miles south of the town of Kersey, Colorado. The site is located northwest of the intersection of Weld County Road 50 (adjoining south of the site)and Weld County Road 51 (adjoining east of the site). The location is shown in Figure 1. According to the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM) Community Panel Number 0822660775C, Weld County, Colorado, dated September 28, 1982. The site is located within a Flood Zone "X". Zone"X" is described as an area outside the 0.2% annual chance flood plain. FEMA Map showing the approximate site location is shown in Figure 2. • • ENERCON E R C O N (405) 722-7693 3 dC DRAINAGE REPORT P LA SALLE GAS PLANT all Midstream. , ,� :40,4 -±‘,1 -r •� _t_1 r�l r , ;rip .govoT N AG JO J � )♦ ! ` _ 4698 vj _ t y KZ OI! wa�• r rn LIa ._' ` ,l \ — -_ �J`." -.. y'" r _ 1 . ' r tF PtE SA U.- L ," S �� . , _ _ 1 P t I _ 1 _ 8 _ �� r t is t? " 4 t, i — �-1 it ) . ,GREE E -- / ' -� t i /`. 1 . ��v: / t k' , — s . /4 "-N. . 1 '01 • %-- .' .>„...:4-e-, ik n.4 i j'\'_1c y, 1le Iaj l 4 r N...1 VI . k ��!' K n� 4337 j� ki.,* r Ii, . . _ \. , f r J Co % i � `\ TJO . -- SITE_ _ 3 C/ ../e0../e01\ 0 _ j !2e :. e _ /pig F . ►71 6 __ r __�46J3 1.' , ‘..1I 1-, +43 11 -�( 1 _ _ :an • �' , w� - 'tt dee i / ?' r J I / _ }.i' _ 1} ,, 4� . , t4rP &t q \ � l G C • il4)., _✓ htlnlq ' ' t -. - - - t �,� `�j! rN b ' �i.. ' , I . tJ ^� v.- ;el * . 1 j� YJ a _.� Fl � ` ii {(;11.".ii) t },. ise(1 e 1114:1 1 — • in 1 it Nl 1 \ \ } • • 1 • y• a7 a a 1, a C 5 I a.,a L—�r— s'• y!}I 1 i1 • el .r an �` 1 at 0 L/.NOrve r Figure 1 — Site Location a ‘ ��,�`�\\� Project ,; APPROXIMATE SCALE —y_ ) C p 1 ,pr'�f YJG' 0 200�1IEF• `,` lJ�t\I sj V�� i jig' — _ I WI'S MO attain*IPER-1-)RIO lF / 7171 FLOOD FIRM NSUNANCE RATE MAP 7(")t s WELD COUNTY, �---\ COLORADO '-' UNINCORPORATED A RSA , -..- - - _._ .---I_--. PANE. 775 Of 1075 - ......,.... I -- t COMMUNItt m u Inn+\\ 0101.4077SC 12 7 MAi NEV I SE SEPTIMLN Pt 1512 I.a.F1 w+r,. ..even-.r t %NSW+..at..*,n.rot.✓r. ) e _ / 1,.. SR as(On A b+^a • ..-.'Si'.•v.en .aee l .el '.-111 t or throsilhell•SA....tea raw..WSJ.sestet to thy mo.te.the tad Oat". t...•...ay don we hoer weir Figure 2 — FEMA Map ill F 3 ENERCON E R C O N (405) 722-7693 4 dC DRAINAGE REPORT LA SALLE GAS PLANT 0 Midstream. 3.0 Site Layout The general site layout is provided in Figure 3. Figure 3 also shows the general storm water drainage pattern and the proposed storm water detention basin location. \ \\\ z , 1kblk N tR. �� I k� r �� „�, / Detention )ik Basin N \,,lik/A1 ara 0ta _lA. �b \ 1 !'L C o %'I Nhhk ili twiaLwe 'I cl 7111 in ki\M."lEk 1 l , il I : i:011, !c0 mull : L�. L _ Tv fra A , i 4 II a Ill•WISII Ill Err 7 a LigglAi i was lop lerillNi, Et - " 1 It '� � tKla / ugikr• _ hi_ \\ L- Nisi !rim 1 \ f ` , 1 1 1 '1 I 1 n / / I / / / / Figure 3 — Proposed rainfall-runoff Flow Pattern 4.0 Methodology The overall hydrology of the site and hydraulics of the storm water drainage system was analyzed using HydroCAD (Reference 1 ) and FlowMaster (Reference 2) software. HydroCAD utilizes Natural Resources Conservation Service (NRCS) Soil Conservation Service (SCS) TR- 20 methodology to compute runoff. The results are presented in Appendix A - Existing Conditions Hydraulic and Hydrologic Calculations, Appendix B - Proposed Conditions Hydraulic and Hydrologic Calculations, and Appendix C - FlowMaster Analysis. The limits of drainage remained the same as the existing condition. However, there were minor shifts in sub-basin boundaries to accommodate the grading. The rainfall-runoff analysis is performed within HydroCAD software using the NRCS SCS methodology. The standard SCS 24-hour storm is used to identify the rainfall events. The SCS Type II rainfall distribution is the distribution applicable to Weld County, Colorado as shown in Figure 4. The SCS unit hydrograph method is used to transform rainfall to runoff The SCS • E3 ENERCON E R C O N (405) 722-7693 5 DRAINAGE REPORT �� LA SALLE GAS PLANT • Midstream_ curve number method is used to account for precipitation losses during the storm event. Storage- Induction method was used within HydroCAD for reach and pond routing. Site parameters (e.g., elevations, distances, areas, etc.) are determined using AutoCAD (Reference 3) software and the existing/proposed site contours. The increase in runoff due to site development of approximately 14.56 ac will be staged at the detention area. The proposed conditions runoff staged at the detention area will be released at a controlled rate so as to not exceed the existing conditions runoff rate. The detention basin is designed to have adequate storage to provide extreme flood control for up to a 100-Year, 24- Hour storm event runoff from the proposed site. The proposed embankment will be an earthen embankment structure. The embankment slopes are 4:1 (horizontal: vertical). The erosion control plan and details are shown in Erosion Control Plan and Detail Sheets (Attachments D & E) respectively. 5.0 Watershed Delineation The historic onsite drainage pattern for the project site is generally to the east northeast. The rainfall-runoff is conveyed as sheet and shallow concentrated flow across the site. Under the existing condition this project site has been divided into four (4) sub-basins EOB1, EOB2, EOB3, and EOB4 as shown in the Existing Onsite Drainage Map (Attachment A). The existing topography indicates there is a high point (hill) at the southwest corner of the proposed development, which will divert any offsite flows draining to the site from south-southwest • direction. As mentioned earlier, Weld County Road 51 borders the proposed site to the south. The area draining along the west end of Weld County Road 51 is approximately 3.3 acres. This area is represented by sub-basin EOB5. This area is analyzed to design the culvert underneath the proposed access road connecting the site to Weld County Road 51. Under the proposed conditions, the site has been subdivided into four (4) sub-basins POB1, POB2, POB3, and POB4 as shown in the Proposed Onsite Drainage Map (Attachment B). A detention basin is proposed at the northeast corner of the proposed development. Runoff from sub-basin POB I is carried to the detention basin via gravel swale. The runoff from sub-basin POB2 will flow to the catch basin via a gravel lined swale and an 18-inch Reinforced Concrete Pipe (RCP). The catch basin is connected by an 18-inch diameter High Density Polyethylene (HDPE) pipe to drain runoff from sub-basin POB2 to the detention basin. The runoff from sub- basin POB4 will combine with that of sub-basin POB2 and will be carried to the detention basin via 18-inch HDPE Pipe. The runoff from sub-basin POB3 is bypassed to flow as in existing conditions. • ENERCON E R C O N (405) 722-7693 6 mmTftdC DRAINAGE REPORT �'� LA SALLE GAS PLANT 0 Midstream. 6.0 Design Inputs P Rainfall Depth As shown in Figure 4, the SCS Type II distribution is applicable to Weld County, Colorado. The HydroCAD software incorporates the SCS Type II distribution. However, in order to fully describe the rainfall event, the 24-hour total rainfall depth is needed. The National Oceanic Atmospheric Administration (NOAA) Atlas 2 (Reference 4) provides rainfall frequency maps for various events. The total rainfall depths for 5-year and 100-year frequencies are provided in Table 1 and are based on the location of the site as shown in Figure 5 and 6.Irrintimip, Eat set:IA itAnfilTraarbvilV"Will Ili 4 f �*�n4a&4,4wr:t ;Sill:: ; I : pit,,,_ ti:�R�y -- attlio III t ••- ien ..N.ti ■pa , ♦ aaw -� rl,a r Ir gra INS OS •ap II ad gat w ".aaa aa•. .s. • 1 r - ' 7 , �� ;T- j) •a IMP v...Ugaa.Sr rt,.,y p'l.►ia i441040x141141/%v.�v. as asa ■„ . 1d•' un•-•-. I: • s.►1�P/spa*.y' � 'T� i��.��s � • � ♦ r .� / •kl �sal iii to �� , t ate ," : rrr .ir/. 5.;:,: •-- ••. rs::: a ••:1 X11.1 n ns. 1 ��r`rLwna...i.IF..:-• '. ....�•i'+�r ►t• I�j { • • 1 it O�S�' �;a^E b lestrerilliii La Salle t - ' el►" 14 Ilk lit A -„ • Gas Plant . .41. g .■-_a!//•a• 4�11141t ., .to.triltio;:d it Rninf�ll • TS Nu �, ��#itiv •�'��►rs': "Iti•.,;: :!•:I Dist ribut ion + ir�srrai�d�r c• •Intt;•�: Type I t•fl ff NWV �t►�" 1.14W irprhatt i I= Type IA .• ��% � , ` . 4,114 ' I Type II �a0. Ito • .. .t c] Type 1n �r III I for iii • .•v re oap Figure 4 — SCS Rainfall Distributions The rainfall intensity affecting the Site has been referenced from NOAA Atlas 2. The rainfall depths with the proposed site location for 5-year and 100-year for 24-hour events are shown in Table 1 . Rainfall Depths Storm Event for a 24-hour storm (inch) 5-year 2.2 100-year 3.8 Table 1 - Rainfall Depths for 24-hour storm • ID ENERCON E R C O N (405) 722-7693 7 a.. ...----p dC DRAINAGE REPORT rt . LA SALLE GAS PLANT Midstream. 0 Me MO NIS WI WI hi.f 1;1;1 , • is lc; 1 filif '!. 1 �, b .`• i I - .� r \I 111 l8 `� .r �' t el ,�/, Y _: \y y, stJ 1 Gas Plant + - ',� a ' . 1. t `.. �� 1 ) 4, - a1. r • :a Ill;. 1 r • �� I , - _. -a N Uri •• i.Je - .t -�..t.: • _ , t 1 1 /J Y II It cel is, !,..„,,,,,, C1 te ) it 41J .. COWAN flat Ma• I11•••11 1 oO•tvnka or s,r M M**tanning.• _ •.or•.r."n.dr41•••. I tl.nla 0• MMOO Figure 5 — 5-Year, 24-Hour Rainfall 0 • abt -7------. ..1a _ In 1oa 7 trms........___--;-, -- ..7,,... ..I.,,,, � J1,� r;, i ---.1 3.811 cl%._ _ - j '1 ,U � r`' � . Gas Plant LTt1__ IU - . _ w� ."': dal n.1, _11 -5ell '` ••.. +tom 1 ( - n to s _, a it • 444.4• '., 14 -.. ici . 4.4 1 11 liT Lb' ,1P-___ 4,--, i 1 I r ---1 --ft - — ' •, s - J } „tt '' 1 star' i I ` (4% • • I I COLORADO a a a a �1 a NAM a •• ill ' I ■ r COLORADO ......w a r. nenal • a • a 1♦ $ us•wr..—__• .• F-4-4,....„.alt swims�.•f...er.r al "Ill tmn*0.no NM M[LTT{11(w =r41:1 w.-...rir y.D.- ermq Donn Kw- 1a Ws "o. 103 I: • Figure 6 — 100-Year, 24-Hour Rainfall r E N E R C O N (405) 722-7693 8 dC DRAINAGE REPORT LA SALLE GAS PLAN Midstream. T Soil Type The NRCS Web Soil Survey (Reference 5) was used to determine the hydrologic soil group for the site. The soil map shown in Figure 7 identifies that the area of concern has a hydrologic soil group of B. The hydrologic soil group is used for the SCS curve number method. Hydrologic Sod Group—Nha County Colorado,Southern Part Grout SaN Gas M) 3 0 534300 534.03 gg 5.14700 534 .e 5 a 5,35100 535'00 .. . 00 ••.. 5X600 SJ'700 40 7 .7 , . Soll Ratings _ - - ri. � IN A AID A B BID 8 C j C/D D Not rated or not available • Drainage Area Rough Outline • • • t a 2051* 1st ... _ . 40']051' WpStw p 17100Ar% dc As �.e ti la S',11-;. .t a k E j 0 50 ,00 :00 > * A r LNatural Rseotuoss Verb Sod Survey 502011 Consstwsdon Seevbe National Cooperative Sod Survey Paps 1 of Figure 7 — NRCS Soils Map Curve Number The NRCS Technical Release No. 55 (TR-55) identifies the SCS curve numbers (CN) for the various cover conditions and hydrologic soil group. Currently, the site is vacant pastureland. Under developed conditions, there are three types of cover to consider. There are impervious areas (e.g., parking lot, buildings, etc.), gravel lined areas, and open ground cover areas adjacent to the impervious/gravel areas that are bare or maintain short growth. Impervious cover corresponds to a CN of 98. Curve Number of 88 was used for developed conditions; which corresponds to urban industrial area. The open ground cover is categorized as fair condition with 50% to 75% ground cover corresponding to a CN of 69. • ENERCON E R C O N (405) 722-7693 9 _clap DRAINAGE REPORT • -P Midstream. LA SALLE GAS PLANT \ \ a ` 5- er Storm Outte!1(See Note 1' • \\ NYe 8'HDPE Pipe I.E. =4791.10• / 10O-Year Storm Outhil(See Note 11) \ 1 24'HDPE Pipe, I.E. ' 4191.75' L Emergency Sp,,way .\ W= t0 LE.4794 5O • Low Eloh \\ 1 Meth to E , ••,•• c Channel ` A`L \ •, ..`nsty , • . 31:1' -- R, Re ��. p g ) ✓S \.\_, �-� t501_ .a i- / ' GU .acted R e�`r._ 1 ��'`• • NS 1l84 CDR. SECTION 31 \ i1 „vet FOUND 2.5'&C. 6 Concrete Flared PtS ILLEGIBLE N 1 ' t 1 5 Ty ►, t End Section , 1 M �• ; 14, I I 12'SCNu PE Pipe \ // • E = : '�t Appmx 141 LF., Sfape2.13% r�.3) _�_.—�� , �n9uSrrT .Deep ' CatcA Bam /- ' ' • • ' ►, , O PROPOSED SWITCHYARD 1 5 :I1/4sia, 1 0 •1 0 1V 12'HOPE APPROX 12sY125' 3H:1 ' , �` I�v LE. -4795. PROPOSED LEECH FlElO ...+ . jr , --�4� "1 ��, �, � iyplpl p p� APPROX 100x25O cIr, DPE. I Cabs Best \ I 18 HDPEd 18'RCP LE. •4796 CAW 078dRIA . el 1 1,...:Ili •�,... , . .Ile Maas • s.tsoo to srptaa,e) RCP ',. iTv • • I1 1■�1u1I 1 `h:. ~e. � h. NV1i-at� -t71lW��Vtr.�.�l Mpox,00�F, Vn � h • t I. oil ! 3 iorm ..yit'� ro'f • —" Jl1ji \ / Slopa ,20% 'liiiiiiiiiii, Pp-,�IEI i ;qt .,- • - . %; =��i�/�1i 118'RCP I . l. .1 tit!" i (underground) Access Road i �: 1 RipRep �. �� 'rill;v.l� .►� P/ I Approx 40 L.F. , r.�l `I 1'11►irl jr,/,J� Slope 0.50% r .1.1. X11 1.1 . (Weil�a0a0) CP 1 S "------Gravel h ete l' --to,,,, ,1 1 Bottom Width 4' ► W: 1372715.08 1 Depth ,' E• o:3258N2.8B / ` ` r� ` Sloe Slope 3H 1 V Elevation : 4782.33' ' / / 17, Figure 8 — Impervious Cover III rI ENERCON E R C O N (405) 722-7693 l0 dC DRAINAGE REPORT P LA SALLE GAS PLANT • Millstream,. a \ • %Y wINsimanX94.NOM11 ,Op PE P LE.*4791.11 \\, \� I S 9'91IbPbEPG S 4791 11) `\ toollati 80.11.2 We MIL 4794 W ItSk flok \.` \ b RVR4D V- , � . _ l'r�r '`fee�/ N$U04 COR.SECTION 31 ��' -4 '. / Al * FOU1!SOLE `� �,�'��•��'/��'�'vrf��/;40-A. �� i I Comb Pl81LLF0lLE i 4 4, 17 SCN 40 POPE Rs It, '�� /'!��I+M� 1: - ' AppOa1411F., S'/, %'•i� 1 •� L :�� ta 8 op9 t13% ilear �1��►/i• .±AP.. /.L _�I Typiu17Dap PIIOPOSED 91MTC111'ARD ``:``7/r*,� 1�. 0 ► 0 1 1V 1t FOPE APPROX 126Y125' /117,1 '1 41�� . 114��I� LE. :4795 PROPOSED LEEC►1FELD �� 1 APPROX 1001?w 1Ur NW Typical 2 Deep ' '�I 11 FF-M11 1 I It ., 10'HOPE IL 4797 woo 0281 OSA ' koh ik - 12 ii lit-hvittcmors-i is i rI '1111'11 . . J it ��%t .. . . -> C' . , -4i .. twatis -d.-nevenrr��1 SIX. " •�� 11'1.5 14 pISitai r.. I j SCM. .. �. , 5■' ) irRCP r 1 1 RiadfliW �� App1ac40i.F. AmpIat Sops 0.50% (a nw9¢WW) CP1 fM 4' P a ly 1372715.01 ` i II WPM 7' SS 1. Este: Est:479239' 1 i t 1 • ,/ Figure 9 - Open en Ground Cover P As described below sub-basin POB2 has an area of 1 . 11 ac. The parking lot area to the east along the access road is part of sub-basin POB2. The paved impervious area for sub-basin POB2 is approximately 0.84 ac and is shown in Figure 8. To be conservative, entire sub-basin is assumed to be impervious for hydrologic analysis only. Therefore, CN of 98 was used for sub- basin POB2. Sub-basin POB4 represents the proposed gravel lined switchyard area corresponding to CN value of 88. Remaining impervious and open ground cover areas shown in Figures 8 and 9 are part of sub- basin POB 1 . The impervious cover area shown in Figure 8 for sub-basin POB 1 is 0.84 ac. The open ground cover area shown in Figure 9 for sub-basin POB 1 is 2.83 ac. The remaining drainage area of 9.76 ac ( 13.43 ac - 0.84 ac - 2.83 ac) for sub-basin POB 1 is gravel. The composite CN value for sub-basin POB 1 is determined as follows: CNimpervious * Areaimaervious + CNonen * Areaopen + CNgravel. * Areagravel Drainage Area CNpoBI = (98 * 0.84 ac + 88 * 9.76 ac + 69 * 2.83 ac) / 13.43 ac = 84.62 = 85 Sub-basin POB3 comprises of access road just east of parking lot to the County Road. The gravel road is proposed to be gravel lined. Therefore, CN of 88 was used for sub-basin POB3. Similarly sub-basin POB4 comprises of gravel lined switchyard area. Therefore, CN of 88 was • used for sub-basin POB4. ID ENERCON E R C O N (405) 722-7693 11 d,/ }r� DRAINAGE REPORT M d Pram LA SALLE GAS PLANT • Design Length and Slope for Time of Concentration HydroCAD utilizes SCS TR-55 method to determine the time of concentration (Tc). The SCS TR-55 method consists of categorizing portions of the hydraulic length into overland flow, shallow concentrated flow, or channel flow. The travel time for each segment of flow is summed to result in the time of concentration. Weld County Drainage Manual (Reference 6) recommends minimum Tc value of 10 minutes for non-urban watersheds. The time of concentration is estimated using initial sheet flow and channelized flow within the ditches. HydroCAD analysis (Appendix A and B) indicates that the estimated Tc value for each sub-basin and storm event is less than 10 min. Therefore, Tc value of 10 min. was used for runoff analysis. The sheet flow and channelized flow characteristics (length and slope) are determined using the grading plan (Attachment C) for the site. The initial overland, sheet, and channel flow lengths used in HydroCAD are summarized below in Table 2. The initial overland flow length of 100 feet (ft)was used for each sub-basin. Initial Overland Sheet Flow Channel Flow Sub- Area Flow Basin (ac) Length Slope Length Slope Length Slope (ft) (ft/ft) (ft) (ft/ft) (ft) (ft/ft) Existing Conditions EOB1 5.52 100 0.0263 1,000 0.0263 - - • EOB2 7.82 100 0.0279 700 0.0279 EOB3 0.92 100 0.0350 415 0.0350 - - EOB4 0.28 100 0.0240 355 0.0240 - - Total 14.54 Access Road Area EOB5 I 3.3 I 100 10.0200 I 1,000 I 0.02 Proposed Conditions POB1 13.43 100 0.030 - - 975 0.018 POB2 1.11 100 0.022 225 0.022 205 0.005 POB3 0.02 100 0.029 450 0.029 - - POB4 0.02 100 0.0162 139 0.0162 Total 14.56 Table 2—Length & Slope Inputs for Tc Determination • ENERCON E R C O N (405) 722-7693 12 dC P DRAINAGE REPORT - LA SALLE GAS PLANT • Midstream. Storage Volume The storage area at each elevation was determined using the AutoCAD 5 ft and 1 ft interval contours. The storage areas were then used to determine the storage volume. The storage areas are shown in Figure 10. The storage volume is presented in Table 3. \\\) 4790' 4795' N4eN Figure 10 — Storage Area Elevation Area Volume (ac-ft) (ft) (ac) Incremental' Cumulativeb 4790 0.4608 0 0 4791 0.5279 0.4944 0.4944 4792 0.5973 0.5626 1 .057 4793 0.6690 0.6332 1 .6902 4794 0.7430 0.7060 2.3962 4795 0.8194 0.7812 3. 1774 Table 3 — Storage Volume a) Incremental = (Area X + Area Y) / 2 b) Cumulative = Incremental X + Incremental • EN E R C O N (405) 722-7693 13 dc DRAINAGE REPORT LA SALLE GAS PLANT • Midstream. As indicated by HydroCAD Proposed Condition results (Appendix B), the 100-year runoff volume is 2.994 ac-ft. The proposed truck rack will also drain to the detention basin. In addition to rainfall-runoff an additional volume of 11,500 gallon (0.0353 ac-ft) may drain to detention basin from tanker truck release. Therefore,the combined volume from 100-year rainfall-runoff and tanker truck is 3.0293 sc-ft. Table 3 indicates a total volume of 3.1774 ac-ft; which is more than combined volume of 100-year rainfall-runoff and tanker truck Manning's Roughness Manning's roughness coefficients used in hydraulic analysis utilizing FlowMaster are listed below in Table 4. Material Manning's Roughness Coefficient Gravel 0.029 HDPE 0.010 RCP 0.012 Table 4—Manning's Roughness Coefficient Source: Chow Book(Reference 7) 7.0 Calculation Hydraulic and Hydrologic Calculations • The overall hydrology of the existing and proposed site conditions was analyzed using HydroCAD software. The existing condition results are presented in Appendix A. The proposed condition results are presented in Appendix B. Resultant rates of runoff for the various frequency storms are summarized in Table 5- Runoff Summary. The proposed conditions will increase the peak storm water runoff. The increase in runoff due to change in land cover will be staged at the detention basin. The proposed conditions runoff detained at the detention basin will be released at a controlled rate so as to not exceed the existing conditions runoff rate. The proposed storm water drainage structures (i.e. swales, storm drain pipe, and detention basin) have been designed to have adequate capacity to convey discharges from up to a 100-year, 24 Hour storm frequency. The hydraulic capacity of the proposed drainage system was assessed using the FlowMaster software. The proposed detention basin is 5 ft deep with a crest elevation at 4794.5 ft and a 6 ft crest length of approximately 10 ft. The detention basin has three outlets which involve pipes for 5-year and 100-year runoff and an emergency spillway. An 8-inch HDPE pipe has been proposed to discharge 5-year rainfall-runoff. The invert for 8-inch HDPE pipe is at elevation 4791.10 ft. A 24-inch HDPE pipe is proposed to discharge 100-year rainfall-runoff. The invert for 24-inch HDPE pipe is at elevation 4791.75 ft. A concrete spillway (emergency spillway) is located at elevation 4794.5 ft near the northeast end of the detention basin. Additionally, an 18-inch RCP is proposed at the entrance to convey the storm water runoff across the access road. • ENERCON E R C O N (405) 722-7693 14 DRAINAGE REPORT -.P LA SALLE GAS PLANT • Midstream. As indicated in Table 5 the total runoff due to 100-year rain event is 21.70 cfs and 54.98 cfs under existing and proposed conditions respectively. The results indicate the total discharge from 24-inch HDPE pipe is 19.29 cfs which is less than 21.70 cfs. The results also indicate that all storm frequency events are maintained below the detention basin embankment crest elevation. Peak Flow (cfs) Drainage Area Sub Basin 5-Year 100-Year Storm Storm Existing Conditions EOBI 1.31 7.35 EOB2 2.31 12.35 EOB3 0.29 1.53 EOB4 0.09 0.47 Total 4.00 21.70 Access Road Area EOB5 I 1.05 I 5.49 Proposed Conditions POBI 19.17 46.02 POB2 2.94 5.15 POB3 0.04 0.09 POB4 0.89 1.96 Total 23.04 53.22 • Table 5—Runoff Summary Note Composite hydrograph presents peak flow at the design outlet point. Individual drainage areas represent unrouted peak flows. The flows within the proposed pipes and swales were analyzed using FlowMaster software. The runoff from sub-basin POB2 will drain to the proposed gravel swale just east of the parking lot area and then cross the access road via 18-inch RCP. A catch basin has been proposed on the north end of the proposed access road. An 18-inch HDPE has been proposed to connect the catch basin to the detention basin. Please refer to the Proposed Onsite Drainage Map (Attachment B) for catch basin and pipe location. The results from the FlowMaster analysis are shown in Table 6. • ENERCON E R C O N (405) 722-7693 15 DRAINAGE REPORT P LA SALLE GAS PLANT • Midstream. 100-Year Runoff Slope Depth of Flow Velocity (cfs) (ft/ft) (ft) (ft/sec) Swale (POB1) 46.02 0.018 1.15 6.27 Swale (POB2) 5.20 0.005 0.57 2.16 18-inch RCP(POB2) 5.20 0.005 0.88 4.84 18-inch HDPE Pipe 7,11 0.0088 0.80 7.44 (POB2 and POB4) 12-inch HDPE Pipe 0.96 0.010 0.25 6.09 (POB4) Swale(POB4) 0.96 0.0162 0.39 2.11 18-inch RCP (Access 5.49 0.012 0.70 6.83 Road Culvert-POBS) Table 6—FlowMaster Analysis Results Water Quality Capture Volume(WOCV) Calculation As indicated in the Weld County Drainage Manual, the required WQCV can be estimated using • the following equation: WQCV =a(0.91 13- 1.19 12 + 0.78 I) (Reference 6; Equation 3-1, Page 930) Where: WQCV=Water Quality Capture Volume (watershed inches) a= Coefficient corresponding to WQCV drain time I=Imperviousness (%) As indicated in the Drainage Manual (Reference 6), the value of coefficient "a" ranges from 0.8 to 1.0 depending on drain time. The value of coefficient "a" chosen was 0.80 corresponding to 12 hour drain time. The Drainage Manual indicates a percentage imperviousness value of 80 for light industrial facilities. Therefore,the value of I was chosen to be 0.80. WQCV = 0.80 (0.91 * 0.803- 1.19 * 0.802+ 0.78 * 0.80) =0.80 (0.46592-0.7616+ 0.624)watershed inches =0.262656 * (14.56 ac) * Oft/12 inch) =0.3187 ac-ft<0.4944.OK As mentioned earlier, the invert elevation for the 8-inch HDPE Pipe is 4791.10 ft. Therefore, there is one (1) foot of water quality storage available. Table 3 indicates that for the first one (1) foot of the detention basin, the available volume is 0.4944 ac-ft. The WQCV is less than the available volume. • ENERCON E R C O N (405) 722-7693 16 DRAINAGE REPORT ---P LA SALLE GAS PLANT • Midstream. 8.0 References 1) HydroCAD 8.0, HydroCAD Software Solutions LLC, P.O. Box 477, Chocorua, NH 03817. 2) FlowMaster 3.1, Service Pack 3, Open Channel Design & Analysis, Haestad Methods, Inc., 37 Brookside Road, Waterbury, CT 06708-149. 3) Autodesk, AutoCAD Lite Desktop Software, 2006. 4) U.S. Department of Commerce, National Oceanic and Atmospheric Administration, and National Weather Service's NOAA Atlas 2 Precipitation- Frequency Atlas of the western United States, Volume- III Colorado, prepared by J.F. Miller, R.H. Fredrick, and R.J.Tracey, 1973. 5) United States department of Agriculture, Natural Resource Conservation Service, Soil Data Mart http://soildatamart.nrcs.usda.gov/. 6) Urban Drainage and Flood Control District's, Denver Colorado — "Urban Storm Drainage Criteria Manual", Volumes 1, 2, and 3;, June 2001 Revised April 2008. 7) Chow, V.T., "Open Channel Hydraulics," McGraw-Hill,New York, 1959. • END OF REPORT • CD E N E R C O N (405) 722-7693 17 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A • 1S < 25 > ( 3S ) EOB1 EOB2 EOB3 K4S ) EOB4 • < 5S > Access Road Area ill Subcat Reach on • Link Drainage Diagram for La Salle Gas Plant_Exisitng Conditions ..---\____ Prepared by {enter your company name here} 5/24/2011 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC Page 33 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A • La Salle Gas Plant_Exisitng Conditions Prepared by {enter your company name here} Page 2 HydroCAD®8.00 s/n 004197 ©2006 HydroCAD Software Solutions LLC 5/24/2011 Area Listing (all nodes) Area (acres) CN Description (subcats) 3.300 69 50-75% Grass cover, Fair, HSG B (5S) 16.270 69 Pasture/grassland/range, Fair, HSG B (1S,2S,3S,4S) 19.570 • • Page 34 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A • La Salle Gas Plant_Exisitng Conditions Type II 24-hr 5-year Rainfall=2.20" Prepared by{enter your company name here} Page 3 HydroCAD®8.00 s/n 004197 ©2006 HydroCAD Software Solutions LLC 5/24/2011 Time span=1.00-72.00 hrs, dt=0.05 hrs, 1421 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: EOB1 Runoff Area=5.520 ac Runoff Depth=0.29" Flow Length=1,100' Slope=0.0263'/' Tc=16.2 min CN=69 Runoff=1.31 cfs 0.134 af Subcatchment 25: EOB2 Runoff Area=9.550 ac Runoff Depth=0.29" Flow Length=800' Slope=0.0279 'P Tc=11.5 min CN=69 Runoff=2.82 cfs 0.233 af Subcatchment 35: EOB3 Runoff Area=0.920 ac Runoff Depth=0.29" Flow Length=515' Slope=0.0350 'P Tc=10.0 min CN=69 Runoff=0.29 cfs 0.022 af Subcatchment 4S: EOB4 Runoff Area=0.280 ac Runoff Depth=0.29" Flow Length=455' Slope=0.0240 'P Tc=10.0 min CN=69 Runoff=0.09 cfs 0.007 af Subcatchment 5S: Access Road Area Runoff Area=3.300 ac Runoff Depth=0.29" Flow Length=530' Slope=0.0250'/' Tc=10.0 min CN=69 Runoff=1.05 cfs 0.080 af Total Runoff Area = 19.570 ac Runoff Volume =0.477 af Average Runoff Depth = 0.29" 100.00% Pervious Area= 19.570 ac 0.00% Impervious Area= 0.000 ac • • Page 35 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type II 24-hr 5-year Rainfall=2. 20" • Prepared by {enter your company name here} Page 4 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 1S : EOB1 Runoff = 1 .31 cfs @ 12. 13 hrs, Volume= 0. 134 af, Depth= 0.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs. dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.20" Area :ac) CN Description 5.520 69 Pasture/grassland/range, Fair, HSG B 5.520 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1 .5 100 0.0263 1 .09 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 14.7 1 ,000 0.0263 1 . 14 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 16.2 1 , 100 Total Subcatchment 1S: EOB1 Hydrograph / ; I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I 1 I I I I • 1 I 1 I II I I I II I I I I IIIIIIIIIIIIII ❑ Runoff' 1 .31cfs I I I ; ; ; ; ; ; ; 1 I . : I I l : ; II Type II' 244ir 5-year I I I I II I III I I I II I I I I I I I I I I I I III I I I II I I I I IIII I II I I " 1 I I II " ( II I II I I 1 I I I I I 1 I I I I I I I I I I I I I I I I I I IIII I I I II I I I I IIIIIIIIIIIIII I - I I l i l I I I I I ; III Rtin,�ff IT ea'=5.520- ac 1 - I I I I I IIII I I I II I I I I I I p IIIIIII II I ; ; ; : : ; : : : : RurnOff VQIUr i0 134 if 0 I I I I I IIII I I I III I I I I I I IIII I I I III I I I I I I I I 41 - I I I I 1 I I I I ' I I I I ' 1 ' ' I Runoff: Depth=0 .29" I I I I 1 I I I I I I I I I I I t I I I 3 I I I I I I I I I I I I 1 I I 1 I I O 0� I � � � ; ; � ; ; ; ; ; ; ; ; ; ; I*IbwLength=1 ,100' Li. I I I I / I I I I I I I I II I I I I III I I I I il IIII ' III II II III Slo a=0.1)263 '/' 1 1 I I I I I I I I I I II I I I I I I 1 h 1 1 I t I I I I I I I I I I I I I I I I I I I I I I I I I, I I I I I IIII I I I II I I I I I I I I I Tci1 6.2 mini I I I I I IIII I I I II I I I I I I I 1 I I I I I I 1 II I ! III1111111 I I I: ; / I I I I I I I I I I II : II : I : I : ; CN =69 1 1 I I s I IIII I I I It I I I I lilt I III I - I I I I I IIII I I I II I I I I IIII I III I I I I I IIII I I I I I I I I I I 1 I I I III I I I I I I I I I I I I I I I I I I I I I I I III I I I I I I I I I 1 I 1 1 I 1 I I I I I I I I III I IIII Ala ;/ 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 36 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type /I 24-hr 5-year Rainfall=2. 20" • Prepared by {enter your company name here} Page 5 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 2S : EOB2 Runoff = 2.82 cfs @ 12.07 hrs, Volume= 0.233 af, Depth= 0.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.20" Area (ac) CN Description 9.550 69 Pasture/grassland/range, Fair, HSG B 9.550 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1 .5 100 0.0279 1 . 11 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 10.0 700 0.0279 1 . 17 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 11 .5 800 Total Subcatchment 2S : EOB2 Hydrograph Z : I ; Ilia a I I I I I I II I 1 I 1 I I I I I I I 1 I 1 I a a I I I I I 1 1 1 1 I I I 1 III , - r 1 - T r r r r r 1 1 I I I I —I — -I - T - -r — T — r — r — r — r r — r —I— —1 ❑ Runoff , I 1 t I I I I I I I I I II I 1 1 , I IIIII 3J I 2.82 cfs I a ii I 1 I a a I I a a Illia 1 I 1 1 I I I I 1 1 1 I 1 1 ? Jill I I I III 1 1 1 1 1 11 I I Type II 24`hr �5,-year I 1 1 1 I 1 I III 1 I 1 1 I 1 I I 1 1 I I 1 I III I 1 I I 1 I 1 1 1 1 1 1 I I I i I 1 1 i I I la l [ Rainfall=2.20•! - I I 1 I I 1 1 III 1 I I 1 1 I I 1 1 1 1 1 I 1 I ' I ! I I I II I 1 I ; 1 1 1 1 1 ; I ' Ronoff Area=9 .550 a©_ - - -�- -�- I - - i - -la- - + - h - 1 - r -la- -r -I , � _ I I 1 1 1 1 1 1 I I I I I 1 I I 1 I I 2- I 1 a 1 I 1 1 I I I 1 1 I 1 I I Run°f volume=0,2;33 I I a I 1 a a a a I I I a a I I 1 1 a I 1 I a a a I I 1 a a I I I I I 1 I , I V I I a I I ilia I 1 1 a 1 I I a a I Runoff 1 Depth=0.29„ I I I I I 1 1 1 1 1 1 1 1 1 I I I 1 I 1 r I 1 1 I I 1 1 1 1 1 I I 1 1 I I I I 1 I I I 1 1 Iii Fli 0 " " " " I ' FIoLlet�gth-800ri: ' I 1 a I I I I I 1 1 I 1 I I 1 I I I I 1 I wl I I I I 1 I I I 1 1 1 1 1 1 I 1 I I I I I 1 1 1 1 1 I i I e_I 1 1 I 1 1 1 1 ] I I I I I I 1 I I 1 I I _IS!lope=0 .0279 , - I 1 I I 1 I I I I I L a a I I I I I I 1 _ I � I I a 1 I I I 1 I I I I 1 la I I I I I I 1 I 1 1 — I 1 a 1 1 1 Ilia I 1 I if r I 1 I la I 1 I i I I a I 1 a 1 1 1 ilia 1 1 1 ii I I I 1 I 1 1 1 1 i '' c=1 1 5 min I I a 1 1 1 1 1 1 I 1 1 1 la 1 1 I I a a a a a I I I I a I 1 1 alai I 1 1 al 1 I 1 I 1 1 1 1 I I I I 1 mii I I a I I 1 a all 1 1 1 al I 1 I 1 I I 1 1 I I I 1 I 1 1 1 C N.49 1 I I 1 I I 1 1 I I 1 1 I 1 I 1 I I , 1 I a I I I I I a 1 1 1 1 I 1 1 I 1 1 Ilia I I I 1 I I 1 I I I a I I I I I I I I I 1 Ilia I I 1 la a a I I I I I I I 1 1 1 I 1 1 1 1 I 1 I a 1 I la la I 1 I alai I I mall al 1 1 1 1 I I I I I a al t I I am 1 I i I ' Imam I I 1 I I - 1 I I I I I I I I I 1 i , ii mail I I I I I 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 37 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type II 24-hr 5-year Rainfall=2. 20" iPrepared by {enter your company name here} Page 6 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 3S : EOB3 Runoff = 0.29 cfs @ 12.05 hrs, Volume= 0.022 af, Depth= 0.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.2011 Area (ac) CN Description 0.920 69 Pasture/grassland/range, Fair, HSG B 0.920 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1 .4 100 0.0350 1 .22 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .6011 5.3 415 0.0350 1 .31 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 6.7 515 Total , Increased to minimum Tc = 10.0 min Subcatchment 3S : EOB3 Hydrograph r r r - r - I - I i , I1 r -�. I I I I I I + I I I I 1 I I + I I I I I I I I I I I I p Runoff • 0.32' _ I l 1 L L L L I_ I I I 1 1 .1 L L L t __ I ._1 ..I -1 1 1 1 L L L I I I 0.29 cfs I I I- I I I I I IIIII I I I I I I I I I I I I I 0.3 . - ,- - ; I , I I II I „ I I I I I I I I I "F ,-- e �1I: 24;-hr;5 ;ear I I I I , I I I I I I I 1 1 I I I I I I Y�' I I Y 0.28 1- L_ - I - -1 7 - Y t r r r 1 I I I 7 7 7 'r - r - I" r _. I - I I I I I - , -i r ' 0.26-? t_ I I I . 1 1 1 L L L I_ II I II _II 1I 1 LI L LI IR L I ai nfa I i=2.2 0" - i I I I IIIIII I I I I 11111 1 I I I I I I I I I I 0.24= I ; ; i T r r ; ; ; ; : ; 4 - Runoff-Aj"ea=0.920 ad- - 0.22- / I I I I I I I I I I I I I I I I I I I I I I I I - .I - - i- "-I - - - 1 - 4 - ± - - - I- - -I- -1- -I- ; - ; - 1 - r - I I ' - t- - 0'2-. I I I _ � �. 1 L L 1 1 1 1 1 I 1 1 runoff-Volume=002 - a I I I I 1 1 1 1 I I I 1 1 I III to I I 0.,8= I T r - r - ,- -,- - ; - 11 - 4 - Runoff Depth=0 .29"- - 0 0.16= I I I I I I I I I I I 1 I I I I I I I I I I 1 Iow ILen I =515, u- 0.14- • 1 I I I I I I I I I I I I I I I I I I I I I I I I I - 1 i I I I I I I I I I I I I I I I I II I I I I I 0.12: t I I I I I I I I I I I I I I I I I I I I Slope=_0 0350 .'/' - - - - I - - - - Z 1 -r r r r r I I 1 -I 1 1 r - r - r - r- I I I 'I ' t - I I I IIIIII I I I I I I I I I I I I I I I I I I 'I I I 1 0'1 - _ I 1 J 1 1 L L L L I_ I I J .I 1 1 L _ L _ LI _ L _I_ _ I . I I -10 -0 - min- I I I I I I I I I I I I I I I I I I I I I I I ■ ICr 0.084: I I I I IIIIII I I I I IIIIIIIIIIIIIIIII 1 I 1 - r T r r I I it I I 1 1 T r r r I 1 I I I 1 T CN 69 0.06E I I I 1 1 1 1 1 I I I I 1 1 t t 1 I 1 I I I I 1 I I 1 ■Y_ w - - -1- -I - 1 - 1 - 1- - 1- - 1- - I- - I- -1- -I- -1 - -1 - -I - -1 - 1 - 1- - t- - F - r- - I- -I- -I - -I - 1 - 1 - -1 - t - t- - • - I I I t IIIIII I ii I IIIIIIIIIIIIIIIIIII 0.04" I I I 1 _ _ I 1_ L L I I I I 1 I 1 1 1 1 1. I. I L_ 1 I I 1 I L L L I - I I I I III I t I I II I I I I I I I I I I I ' 0,02- I I I I I I 1 I I I 1 I I t i I I 1 I I 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 38 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant Exisitng Conditions Type II 24-hr 5-year Rainfall=2. 20" • Prepared by {enter your company name here} Page 7 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 4S : EOB4 Runoff = 0.09 cfs @ 12.05 hrs, Volume= 0.007 af, Depth= 0.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.20" Area (ac; CN Description 0.280 69 Pasture/grassland/range, Fair, HSG B 0.280 Pervious Area Tc Length Slope Velocity Capacity Description (min', (feet) (ft/ft) (ft/sec) (cfs) 1 .6 100 0.0240 1 .05 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 5.5 355 0.0240 1 .08 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 7. 1 455 Total, Increased to minimum Tc = 10.0 min Subcatchment 4S : EOB4 Hydrograph / I 1 I I I I I I I I I I I I I I I I I I 1 1 I I I I I 1 I I I I I I I I I I I I I I I I IIIII II IIIIIIIIIIIII • - I- - I - I I 1 I - T - T - r - r - I- - ,- I -- -1 - 1 - r - r I - r -,- -, I - � - T - r I - r j , , 1 - I - T 1 Runoff 0.095= 1 I I I I 1 I 1 1 1 1 1 1 1 1 1 I 1 1 I I I • 1 1 I 1 I I 0.09 cfs - T I I I I I I i I I r , t I I -I -I I I .1 - -1 - i - ] 0.09- I- _ I_ -I _ I I I I I I I I I I I I I I I I I i I t 0.085 I ; I I I ; I ; ; I I ; ; I I I ; Y"ype ;11 ;24—h r 5-year - I II I III II 1 I 1 I I I 1 I I 1 I I 1 I I I I . I //� 0.08- I__ II 1 1 1 1 1 1 " " " " " " I I I 1 I I I I 1 1 1 1 I _ Rainfall-2.20" II i IIIII I 1 1 1 1 1 1 1 1 1 I 1 1 1 0.075-2 '._ _ 1 I I I I I I I I I I I I I I I I I I I I I I I It i I 0.07= I -I ;- 0 1 i R� JAi'ea=0 .280 1Q 0.065- I I 1 _ 1 L L I 1 1 1 1 1 L L L In: . f I---0 . 00i -tai - 1 0.06- I I 1L L L I I I J J I L L 1. �tt,O OL\� O • II I II I II I 1 1 1 1 1 I I I I ' III 0.055= - I I I l _ 1 L L I I I J J L _ L _ L - L _I_ _I- I U I II I II 1 11111 I III iRunoffDIe 4k-fl .29' - 0.05= I_ I I I i I I - 1 _ I L L I I I J LL L _ L _ _II II II 11111 III �° 0.045' _I- L _ l _ 1 _ L _ L _1 _1 _I J J 1 1 L L 1_ I_ I - Flow Length=455' III II I II I 11111 I I I I I L I i I I I ill 0.04-E. I_ _I_ _I -I l 1- L L I_ I I -.I -I l .I- _ L _ L _I- _I- -1 _ -1 _ J - _ I. I 1 1 I I I I I I I 11111 I I I I I I l lope__ m410 / 0.035= ,_ _I- - + - I- I I II- I- I- I I I -I + - + - a J + 4- I 1 I I 1 1 1 1 1 I 1 1 1 1 1 I I I 1 1 I I I I i I I L I 0.03- i- -1- -t- -' - + - + - 1- - I- -I- -I- -1 - -I - -I - + - F - I- - F- -1- -1- -1- -I - -F - + - f- - I al A ..,�■ I I I IIIIIIIIIII 1 I I I I I I I I ITC-1-O.O- min - 0.025= r -r -I- ilk + - + - I- - l- -I- -I- -I- -1 - 1 - F - 1- - I- - I- -I- -1- -1 - -I - -1 - i - r - t - t- - 1- -I- -I - -1 - -I - + - + - III I I 1 1 I 1 1 I I 1 I I I I I 1 I I I I I I I I -I- -r -I- r - r r I I I -1 - ti - r - r - r - r -I- --I- -1 - -1 - - 1 - r - r - r - t- -t- "laymen Ny�6a 0.02= - I I I IIIIIIIIII I IIIIIIIIIIIIIIIII 0.0154' ,- 1- - I- -I' -1 -- -�- -:- -II- -; - - I' r - r I 1 1 1 1 1" - r - r - r -I- -1- 1- 1 - 1 - ? - r - r I I I I 1 7 - r - 0.01=' I I I I "- - I- -I - i - I - r - T - r - r -I- -1- 1 - 1 - 1 - T - r - r - r - t- -I- -I 1 - -1 - 1 ._ T - -I- -t- -II - 0.005= b._ te ,4 I I I ' „ I I I I I I I I I I I I I I I I I I IIII I 0 - I 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 39 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type II 24-hr 5-year Rainfall=2. 20" • Prepared by {enter your company name here} Page 8 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 5S : Access Road Area Runoff = 1 .05 cfs @ 12.05 hrs, Volume= 0.080 at Depth= 0.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.20" Area (ac) CN Description 3.300 69 50-75% Grass cover, Fair, HSG B 3.300 Pervious Area Tc Length Slope Velocity Capacity Description ;min) (feet) (ft/ft) (ft/sec) (cfs) 1 .6 100 0.0250 1 .06 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 3.0 430 0.0250 2.37 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 4.6 530 Total, Increased to minimum Tc = 10.0 min Subcatchment 5S : Access Road Area Hydrograph I 1 I I I I I I I I I I I I i I I I I I I I I I I I I I I I I I I I I I I I I I I i IIII I I I III I I I II I I I I I I I I I I I I I I I I I I 1:1Runoff` I III I I I II I I I I I I I I I I II I I I I I I I1 .05 cfs I I I I I I I I I I I I I I I I I I I II I I I I I I I I I I III I I I II I I I I IMO III1I r' I I I I -I - , , 7TT rrr1 1 1 1 1 1 � II 2�4�h r 5-Year 1 - I I I I I I I 1 I I I I I I 1 I I I I I I I I 1 I I I I 1 1 1 I l 1 1 t 1 I I I till I I I 1 1 I I I I I I I I I 1 I I I 1 I 1 I t 1 I I I I Rainfall=2.2011 1 I I I I I I 1 1 I I I 1 I I I 1 1 1 1 I I I I I 1 I I I I I I I I I I I 1 I I I I 1., ,`J1 1 I I 1 (.1II 1 I I I 1 1 I 4 I I I I t I I I 1 I I I I I I RMnoff ' �Ya=3 .300 ac I I I I I I I 1 1 1 I I I I I I I I - I I I I I 1 1 1 I I I I I I I I I I 1 1 1 I I I I I ' ' Runoff Volume=040;80 of 1 I I I I 1 I I 1 I I I 1 I I I ^ I I 1 I I I I 1 I I I I 1 I 1 I I 1 i I I I 1 I I i i v I I I I I 1 I 1 1 I I 1 1 1 I I I I I U I I I I I I t I I I I 1 1 1 I I I I I Runoff IDepth=0 .29" I I I I 1 t I I I I 1 I 1 1 I I I 1 , 1 I I I I I 0II II II II II II II II " I FI'oinr' Length=5301 IT I I I I I I I I 1 1 1 t 1 1 1 1 1 t I 1 I� I 1 I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I 1 I I I I I I 1 1 1 I I I I I I 1 1 t I 1 I I I I I 1 I , 1 I I 1 I 1 I I I ISIQpe 0250 / I 1 I 1 1 I I I I I I I I I I I I I 1 I I I 1 1 • I I I I 1 I I I I I I I I I I I I I 1 I 1 I I I 1 I 1 I I cF10.0 min I I 1 I 1 I I I I I I I I 1 I I I I I 1 I 1 1 I 1 1 I I i I I 1 I I I 1 I 1 I I I I I I I I I I I I I I I I I I I CN=69 I I 1 I I 1 IIII I I I 1 1 I 1 I I I 1 I I I 1 I I 1 - I I 1 I 1 I 1 I 1 1 I I I 1 1 I I I I 1 I 1 1 I III I I i I I I I I I till I I 1 I I t 1 1 I I I I I I I t 1 I 1 I i I I I I I I I I I I I I I I I I I I I I I I I I III I I I I 1 1 I I I I 1 I t 1 1 I I 1 I I I I I I I I I III I I 1 1 I I 1 1 I 1 1 I 1 I I I I I I I I I I III I lit 1 1 0 Alamis 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 40 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type 1I 24-hr 100-year Rainfall=3.80" • Prepared by {enter your company name here} Page 9 HydroCAD®8.00 s/n 004197 ©2006 HydroCAD Software Solutions LLC 5/24/2011 Time span=1.00-72.00 hrs, dt=0.05 hrs, 1421 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment IS: EOBI Runoff Area=5.520 ac RunoffDepth=1.14" Flow Length=1,100' Slope=0.0263'/' Tc=16.2 min CN=69 Runoff=7.35 cfs 0.524 of Subcatchment 2S: EOB2 Runoff Area=9.550 ac Runoff Depth=1.14" Flow Length=800' Slope=0.0279'/' Tc=11.5 min CN=69 Runoff=15.08 cfs 0.906 of Subcatchment 3S: EOB3 Runoff Area=0.920 ac Runoff Depth=1.14" Flow Length=515' Slope=0.0350'/' Tc=10.0 min CN=69 Runoff=1.53 cfs 0.087 of Subcatchment 4S: EOB4 Runoff Area=0.280 ac Runoff Depth=1.14" Flow Length=455' Slope=0.0240'/' Tc=10.0 min CN=69 Runoff=0.47 cfs 0.027 of Subcatchment 5S: Access Road Area Runoff Area=3.300 ac Runoff Depth=1.14" Flow Length=530' Slope=0.0250'/' Tc=10.0 min CN=69 Runoff=5.49 cfs 0.313 of Total Runoff Area= 19.570 ac Runoff Volume = 1.857 of Average Runoff Depth = 1.14" 100.00% Pervious Area = 19.570 ac 0.00% Impervious Area =0.000 ac • • Page 41 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type I/ 24-hr 100-year Rainfall=3. 80" • Prepared by {enter your company name here} Page 10 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 1S : EOB1 Runoff = 7.35 cfs @ 12. 10 hrs, Volume= 0.524 af, Depth= 1 . 14" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80" Area (ac) CN Description 5.520 69 Pasture/grassland/range, Fair, HSG B 5.520 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet: (ft/ft) (ft/sec) (cfs) 1 .5 100 0.0263 1 .09 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 14.7 1 ,000 0.0263 1 . 14 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 16.2 1 , 100 Total Subcatchment 1S : EOB1 Hydrograph / , , IIIII I I IIIIIIIII .# / , I -1 - 7 r r I- 7 - 1 t T r r r r - r - r -1 • 13-e13-eI I I I I I I I I 1 I I I I I 1 1 1 1 1 1 p Runoff' 1 1 7.35 cfs ' I I 1 I I I I I I I I I I I I I I I 1- Type II 0 I� I- - I- I I I i 1- I I I I I 1 I -I- I 24-h, - 0 ��a�a 1 M 7 I I I I I I ' till 1 I I I I I I I I II I I IIIII I I II I I I I IIIIIIIIi . I I 1 IIIII I 1 II I I I I I I _I I 1 1 Rai of a I1=3.80" _ I I I _ J J .1 1 L L L L L I I I I I I J _ .J _ I I I I I I IIIII I I II I I I I I I I I I I I I I Runoff A►'rea=5.520 ac I I I I I I IIIII I I II I I I 1 5 I I - I I -4 -4 4 4- III 1 III RUnOfi Vol•ur a a.524 at I I I I I I I I I I I I I I I I I 1 I I 1 1 I 1 I I I 1 1 1 1 1 I I 1 I I I I I 1 - 1 Runoff Depth=1-.14", - -i- - - - -7 - 1 l �1 Z r r r r r 1 I I 1 1 I I r . 1 3 4 I I I I I I 1 1 I I I II I I I I I 1 I 1 1 1 1 III I �,.► IIIIIII '' FIbw Leflgth=1 , 100' u_ I 1 1 1 1 1 1 1 1 I I I 1 I I I I I I II I II I I - 1 11111 I I I I I I I I II I I ' 3 I I I I I I 1 I 1 I I I I I I I I I I I Slope=0.0263 / 1 I I I I I I 1 1 1 I I I I 1 I I I 1 I I I I I i III 1 I I 1 I I I I I I I I I III 1 II 1 � L L I_ I I I _LIT c�16-.2 min ii 2 I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I ! I I I I I I I I I I I I I I I I I I I I I 1 I CN�`69 , 1 �' I IIIII 1 I II I I 1 I 1 1 I 1 I I I I I 1 1 I -_ _rI _ -I - a _ 4 _ 4- - Y - I- - I- - I- I- 1 I 1 I 1 -1 - -1 - a - + - -F - F - - F- .. I I 1 /0of 1 1 I I 1 I I I 1 I I I I I I I 1 1 1 I 1 I I I I I 1 I I I , I I I 1 I I I I I I I I I I 1 1 I I I I 1 I 1 Aii.. :)'_r_ratty I I I I 1 I 1 I 1 1 1 1 1 I 1 I 1 1 I 1 1 J 0 . Allin 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 42 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type II 24-hr 100-year Rainfall=3. 80" • Prepared by {enter your company name here} Page 11 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 2S : EOB2 Runoff = 15.08 cfs @ 12.04 hrs, Volume= 0.906 af, Depth= 1 . 14" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80" Area (ac) CN Description 9.550 69 Pasture/grassland/range, Fair, HSG B 9.550 Pervious Area Tc Length Slope Velocity Capacity Description (min; (feet) (ft/ft) (ft/sec: (cfs) 1 .5 100 0.0279 1 . 11 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .6011 10.0 700 0.0279 1 . 17 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 11 .5 800 Total Subcatchment 2S : EOB2 Hydrograph �.. I I I 1 I I I I i I I I I i 1 I I I I I I I I I I I I 1 I I I I I I I I I • - I- - I -I - -t - - T - T - r - r - r - r - r I I I I -I - , - -r - 1 - r - t - r - r - r p Runoffy 16= _,_I 15.08 cfs 2 _ 2 _ 4, _ 4, ' ' 1 I I I I I I I 15= - - - ; ; - ; - ; - ; - ; - ; - - ; - - ; - ; - ; ; Type II 24-hr1QO;-year, 14' I 1 I I I I 1 1 1 1 1 1 1 1 1 I I I , Ra i nfe l l=3I:80'F 13- LLLI1 -I- -I - -1 - -I _ + _ + _ + - + - L - L - 1- _ 1- - I- - I_ 1 1 I I - y. _ 1 _ _ I I I I I I I I I I I I I I I I 12= - _I I _I _ J _ 1 _ 1 _ 1 _ 1 _ 1 _ 1 _ L _ L _ 1. _ I_ _1-Ruinoff Area=9 .550 _ad _ I 1 1 11 I I I I I I I I 1 I I I I I 1 1 I I I I 1 I 1 T T T r r I - r�4 --volume-0 90# oaf 10= I I I I 1 I 1 1 1 1 1 1 I 1 I 1 1 ■ - - I- - I- -I- - -1- -1- -1 - -1 - i - t - t - + - r - r - h - 1- - r - r -I- -I- -I- - 1- - h I )_,J F . Z 1 I II. L L : ;_ ;_ Runoff, Depth=1-:-1i" I I I I 1 1 1 I I I I I I 1 I I 1 I I I I I I I I I T T I I I I I I 1 I I I 1 I 11 Flow Length:800' u. I T r 1 T I I I II I I 1 I 1 -I- -I - -t - -1 - Y - -t -t 1- t - r - r - r - r - r I I I I - S 6- 1 I I _I _I J J 1 1 1 1 1 L L L L L I_ I- I- I_ �" lope=0 .0279 1 1 I I I 1 1 1 1 1 1 1 1 1 1 I II I I I I I 1 t I I 1 t I I I I I 1 I Tc=1 -1 5- min I , I I I 1 1 1 1 1 1 1 1 1 I II I III 4- I I I I I I I I I I I 1 I I I I I I I 1 I I I -I- -I- - - - 1 7 1 -1 1 1 T T T r r r r r 1 I I I I 1 1 1 l -I CNe59 3- I I I I I I I I I I I I I I I I I I I I I I I I I I I 1■■� I- I I I 1 - 1 4 _I - 1 1 1 1 L L L L l- I_ I I I I I _ I -I -1 1 1 -._ 1 I. _ I - I- I I I I I I I 111111111 I II I III I I I I 1 I I I I I 2- I I I 1 I I I I I I I I I I t I 1 it 1 III I I 1 111111I I 1 1 1 I 1 I I 1 - - 1 - I - 1 _ 1 - III1 1 I I I 1 ti 1 III I I I I I I I I I I 1- I I 1 I I I I I I I I I I I I I I I I I I I I I I Q 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 43 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type II 24-hr 100-year Rainfall=3. 80" • Prepared by {enter your company name here} Page 12 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 3S : EOB3 Runoff = 1 .53 cfs @ 12.03 hrs, Volume= 0.087 af, Depth= 1 . 14" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80" Area (ac) CN Description 0.920 69 Pasture/grassland/range, Fair, HSG B 0.920 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet: (ft/ft' (ft/sec) (cfs) 1 .4 100 0.0350 1 .22 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 5.3 415 0.0350 1 .31 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 6.7 515 Total, Increased to minimum Tc = 10.0 min Subcatchment 3S : EOB3 Hydrograph 1 I I I ! I , I I I I I I I / I I I I I I I I I I • I I I ! I I I I I 1 ! I I I I ! I IIIIIIIIIIIII ❑ Runoff! I 1 .53 cfs I I 1 1 I 1 I I II I I I I I I 1 1 ! ! I I I I I 1 I I I I I I I I I II I I I ! I III I II 1 1 I , I I I I I I I I I I I I I I I 1 i I t I I I I I I II I Type 1124-h r 100-year I I I 1 I 1 1 1 1 1 I I I II I I I I I I I I I • I I , 1 I I I I I I I 11 I I I I 1 1 I 1 Rainfall=3.80„ I I I I 1 I 1 I 1 I 1 1 I I t 1 1 1 I I 1 1 I I I 1 I I I I I I I I I I II I I I I III I IIIIIII 1 1 I I I I 1 1 II I I I ' III 'I 1 I I 1 Runoff ' rea=0.920 ac I I I I 1 I I I I 1 I I 1 I I I IIIII I I I I I I I I I I I I - - -; -I- -I- - - 1 - I - -I - ; - ; - ; - ; - , - ; - ; -1- -,- RUflOff Valuri'ii ;87 of mom+ I 1 I I I I I I I I I I I I I II I I I I I I I I I I K4 I I 1 1 I IIIII I I I I I I I I I I Runoff Depth 1 . 14°, v I I 1 I 1 IIIII I I I II I I I I I � 1 I 1 1 1 1 1 I I I I I I I I I I I I I 1 I I I ill O 1 1 1 1 II II II II II II I II 1 i Flow' Length 515' it- I I I I I 1 IIII I I I 11 I I I 1 I - I I 1 I I I IIII I I I II I I I I II I I I I I I I I I IIII I I I II I I I I 11 I t pI I e= I I 1 I 1 I I 1 I I I I II I I I I II I lo . $50 / I I I I I IIII I I I II I t 1 I II 1 I I I I 1 I I IIII I I I II I I I 1 II 1 ! ! I 1 till II 1111 c=10.0 min I I I I I : III 1 1 I I I II I I I I IIII I IIIIIIII//�� I ! I I F 1 1 I I I I I I I I I I I I I I 1 1 I I I I 1 / _N-69 I 1 I 1 ', I I I I 1 I I I I II I I I I I I I I I I I I 1 v - I I I pQS I I I I I I I I I I I I I I I IIII I IIIII I I 1 I I ) 1 IIII I I I II I I I I till I IIIII I II ! 1 I t 1) 1 I I I I 1 I 1 I 1 1 1 I 1 I I I I I I I I I I I I I 1 I I '' 1 1 I I I I I II I II I 1 1 1 1 I I 1 1 1 1 I I sari, I I I 1 I I I 1 I I I 1 I I 1 I I 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 44 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type II 24-hr 100-year Rainfall=3. 80" • Prepared by {enter your company name here} Page 13 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 4S: EOB4 Runoff = 0.47 cfs @ 12.03 hrs, Volume= 0.027 af, Depth= 1 . 14" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80t1 Area (ac) CN Description 0.280 69 Pasture/grassland/range, Fair, HSG B 0.280 Pervious Area Tc Length Slope Velocity Capacity Description (min) ;feet) (ft/ft) 'ft/sec) ;cfs) 1 .6 100 0.0240 1 .05 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 5.5 355 0.0240 1 .08 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 7. 1 455 Total, Increased to minimum Tc = 10.0 min Subcatchment 4S : EOB4 Hydrograph 1 - -r - , - - r - r I 7 7 r r t • 0.52_ ' - L - ' I _ J _ 1 _ L _ I ` I I + 1 I I I I I I I I I J I I I I I I Runoff' 0.5= - I- • - 7 - r - r -r -r -r -1- -I- 1 - 1 - 1 - 1 - r - r - r - t- I I I - -I - 1 - 1 - 1 - r - r - r - L. - 1_ 0.47 cfs - 1 - L - t - 1- -I- -I- I- J- -I - J 1 - 1 - ' 1 - L - L - I 0.48 - _ I I i I 1 I 1 1 1 1 I ( I I I I I I I 0.467 - r -r I I -I - 7 - r - r - r -I- -I- -I- -I- -1 - 1 - 1 - 7 - Type II 24-hr-100-year - 0.44 tilt - 1 — 1 — 1 — L — L — 1— —I_ -I- -I- J— J — .1 — J — 1 — _ - I I I I I I I I I 1 1 I 1 I I I 1 I I i I I I i ii 0.42= r —I- -I— - 1 - 7 - 7 - r - r - r - r -r -r- -I- 1 - 1 - 1 - 7 - r - r r — r —r- Rainfall—a80e_ _ 0.4 -- I I 1 J_ 1 1 I I I I I I I 1 ,4 I I I I I_ I 1 I I I 1 I I I 1 1 1 1 I I I 1 I I I I I i flit II 0.38 . 1- -I- -1- - - -r - 1 - 7 - r - r - r -r -I- -1- -1- -1 - y - 1 - Y - 1 x - 0.36- I I I _ J 1 1 L I I 1 I 1 1 I J J , _ Runoff Area-1'0 .280 Rio-. III 1 1 1 1 1 1 1 1 1 1 1 1 I i 0.341 ' r -I- -I- - 1 - 1 - 7 — r — r — r —t- -r -1- -1- 1 - 1 - 1 - 0.32= I I I _ J J 1 L L 1 1 1 1 1 J ,J Runoff Volume=0.027 of 1 I 1 ii , , , , , , , , , ,1 I 1 I I I I 1 1 I i - 0.3- I - r -r -I- - 1 7 -r r r r r , i 1 1 1 i _ U 0.28- . L -1_ J_ -I_ JJILLLI II I J J 1 1 - " �. = I I 1 1 I I 11 11 I 11 1 I I I I I Runoff Depth-1 .14 0.26_ r -r -I- — 1 - 7 - 7 — r — r — r —r —r —I- -1- 1 - 1 - 7 - 7 — r — I - I O 0.24- _L _I_ -I- - 1 _ 1 _ 1 _ L - L - 1- _ L _I_ _I_ J- J _ _1 _ 1 _ 1 _ 1 _ L . it 0.22= i - t- -I- -,- - 1 - 1 - 7 - r - r - r -r -r - -1 1 - 1 - 7 - r - r - r -glow I ength=455' 0.2-: I_ _L _I_ _I_ _ _I _ 1 _ 1 _ L1_ 1_ 1 I I_ _I .J .1 1 J. L L L L I$to _ _e-0.0240 ,�T _ I 1 1 1 1 I 1 I 1 1 1 I I 1 1 1 1 I I 1 I 1 i 1 LF7 0.18-i - 1 I 1 i - 1 - 7 - T - r - r - r -r —r -1- -1' 1 - 1 - 7 — T — r — r — r —r r r - 0.16- . L I 11 J 1 1 L L L L 1_ I_ I_ J _ J _ 1 _ 1 _ L _ L _ L _ 1 1 - ` _ L _1111 IIIIIIIIIIIIIIIIIIIi 0.14- - r- —t - 1 - 7 - 7 — r — r — r — r —f- —I— —I — -1 - 1 - 7 - 1 — T — r — r — r —r -1' TC- ■ 0 .0 n- - 0 12= _ I I I _ JILL LLI I I I I J 1 1 L L LI I I + - I- 717 1I I 1I 1 1 I I 1 1 I I 1 1 1 I 1 I I I 1 1 1 I 1 I I I CN �/� - 0.1 - 1 - 1 - 7 — r — r — r -r -r - - 1 7 T r — r — r —r —r —r -1— - 1 =69 0.08- _L _I_ J_ 1 _ 1 1 L L L I 11 I J J 1 1 1. L L L I I I I J _ _ L _ L _ L _ I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 0.06 r -1- --r- -r 1 -- 7 - 7 r r r r 1 r r 1 1 1 7r r r r a I I 1 1 1 1 r — r — r — 1— - 0.04- , _ I I I I 1 _ 1 _ L _ L _ L- _ L_ _I_ _I .. -I .. ..I _ I _ J 1 L L L .I_ I_ 1_ I - - I J 1 1 L L L L i I I I 1 I I I I I t 1 I I I I I I I I I I I I I I I 1 0.02- 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 45 of 46 La Salle Gas Plant Draingae Report HydroCAD Existing Conditions Appendix A La Salle Gas Plant_Exisitng Conditions Type II 24-hr 100-year Rainfall=3. 80" • Prepared by {enter your company name here} Page 14 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/24/2011 Subcatchment 5S : Access Road Area Runoff = 5.49 cfs @ 12.03 hrs, Volume= 0.313 af, Depth= 1 . 14" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80" Area (ac) CN Description 3.300 69 50-75% Grass cover, Fair, HSG B 3.300 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet; (ft/ft) :ft/sec) (cfs) 1 .6 100 0.0250 1 .06 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 3.0 430 0.0250 2.37 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 4.6 530 Total, Increased to minimum Tc = 10.0 min Subcatchment 5S : Access Road Area Hydrograph Zn I I I I I I I I I -1 -I 1 Z r r r - -,- - , T I' - r - • 61 11 111 II 111111 1 1 1 1 I I I 1 1 1 1 1 . Runoff 5.49 cfs 1 1 1 } - �- - - �- - ; ; Type I I. 24-h r _100Ly;eir I 1 1 I I I I I I I I I I 1 I I 1 I 1 1 I 1 1 1 1 I I I I 1 I I 1 1 1 I I I I 1 I 5 III I 1 Rainfall=3.90" 11 1 1 1 1 1 1 I I I II I I 1 1 III ' 1 Ili i I I I 1 I 1 I I I I I I I I I I I I � 1p I 1IS� �I��[ ay AI 1 - J - J - J _ J _ J _ l. I L L I I I I I IRUnoff Areal-3,300- 60 _ - - , - - 1 I 1 I I I I I I 1 I I I 1 1 I 1 1 • 1 I I 4 H RUtidff Voitjrme=0 . 313 of I t 1 I I I I I 1 1 1 I I I I I I ^ 1 I 1 I I I I 1 1 1 1 I I I I I I I I I I - -,- - - ; -I ; ; 4 7 r Runoff; Depth=1 .14" ' lilt II mill 11111 III Flow; Length=530' I I I 1 1 1 1 1 1 1 1 1 1 t 1 I I I II I I I - - - - - - - - - ; - - 4- - - - -; , - - ,S;IQpe= p 50 2- I I 1 1 1 I I I I 1 I 1 1 1 I I I I I I I I I I I I Tc=10.0 min I I I I I 1 1 1 1 1 I I I II 1 I I 1 1 1 1 1 I 1 1 1 1 I I cw -69 - � 1 1- I 1 1 1 1 1 1 1 1 1 I I I II I 1 1 I I 1 1 I I III I I I I I I I I I 1 I IIIII I 1 I II I 1 1 1 1 1 1 1 I III 1 1 IIII I I I I 1 IIIII 1 I I 1 1 1 1 1 1 1 1 1 1 I III 1 I 1 1 1 1 I I 1 1 I I I 1 I 1 I I II I 1 1 1 1 1 1 1 1 III I I I I I I I I I I I 1 I III I 1 I 1 1 I I I I I 1 I I I 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 46 of 46 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B 0 / , / //- \ 1S (\ 2S \ / // 3S \ / PO 1 POB2 POB3 4S 0 POB4 5P Detention Basin • Subcat Reach on Link Drainage Diagram for La Salle Gas Plant_Proposed Conditions Prepared by {enter your company name here} 5/23/2011 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC Page 39 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B • La Salle Gas Plant_Proposed Conditions Prepared by {enter your company name here} Page 2 HydroCAD®8.00 s/n 004197 ©2006 HydroCAD Software Solutions LLC 5/23/2011 Area Listing (all nodes) Area (acres) CN Description (subcats) 13.430 85 Pasture/grassland/range, Fair, HSG B (1S) 0.024 88 Pasture/grassland/range, Fair, HSG B (3S) 0.520 88 Urban industrial, 72% imp, HSG B (4S) 1.100 98 Pasture/grassland/range, Fair, HSG B (2S) 15.074 • • Page 40 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant_Proposed Conditions Type 11 24-hr 5-year Rainfall=2.20" • Prepared by {enter your company name here} Page 3 HydroCAD®8.00 s/n 004197 ©2006 HydroCAD Software Solutions LLC 5/23/2011 Time span=1.00-72.00 hrs, dt=0.05 hrs, 1421 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: POB1 Runoff Area=13.430 ac Runoff Depth=0.94" Flow Length=1,075' Tc=10.0 min CN=85 Runoff=19.17 cfs 1.057 af Subcatchment 2S: POB2 Runoff Area=1.100 ac Runoff Depth=1.97" Flow Length=530' Tc=10.0 min CN=98 Runoff=2.94 cfs 0.181 of Subcatchment 3S: POB3 Runoff Area=0.024 ac Runoff Depth=1.13" Flow Length=550' Slope=0.0290 '/' Tc=10.0 min CN=88 Runoff=0.04 cfs 0.002 af Subcatchment 4S: POB4 Runoff Area=0.520 ac Runoff Depth=1.13" Flow Length=239' Slope=0.0162 'P Tc=10.0 min CN=88 Runoff=0.89 cfs 0.049 of Pond 5P: Detention Basin Peak Elev=4,792.18' Storage=0.641 af Inflow=22.98 cfs 1.287 of Primary=2.57 cfs 0.985 of Secondary=0.00 cfs 0.000 af Outflow=2.57 cfs 0.985 af Total Runoff Area = 15.074 ac Runoff Volume= 1.289 of Average Runoff Depth = 1.03" 90.22% Pervious Area = 13.600 ac 9.78% Impervious Area = 1.474 ac • • Page 41 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant Proposed Conditions Type II 24-hr 5-year Rainfall=2. 20" • Prepared by {enter your company name here} Page 4 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Subcatchment 1S : POB1 Runoff = 19. 17 cfs @ 12.02 hrs, Volume= 1 .057 af, Depth= 0.94" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.20" Area (ac) CN Description 13.430 85 Pasture/grassland/range, Fair, HSG B 13.430 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1 .5 100 0.0300 1 . 14 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 2.4 975 0.0180 6.80 96.89 TrapNee/Rect Channel Flow, Bot.W=5.00' D=1 .50' Z= 3.0 7' Top.W=14.00' n= 0.029 3.9 1 ,075 Total, Increased to minimum Tc = 10.0 min Subcatchment 1S : POB1 Hydrograph I I I I I I I I- i II -I I I I I I I I I I _ C- • 21 II I 1 I I I I I I _ I _ LIIII I 1 I I J I I 1 1 1 I I t I I I I I I 1 1 I I I I I 1 I 1 1111111 I 1 ❑ Runoff` 20- 19. 17 cfs 1 J 1 1 1 1 1 L L L L L 1- 1 II I I I 19= - 1 1- - - - 4 - ; - � - ; - ; ; - ; - , - ; - ; - ; - ; - -;- -;- type II -24 lir;5.year 18= - I- -1- -I I- -I - -I- -t - '1 - t - t - r - r - r - r - r - r - r -1- -1- --I 7 t 17= ;.. -; ; ; ; ; TT - T - r - r - r - r - ir -:- -:- -;- -;- -;- Rainfall=2,20" 16' I I I I I I I I I I I I I I I I I 1 11 I 1 I II I 11111111 1 I I I - 15-? 1 i i � J 1 1 1 .1. 1 L L L L R unoff Area=13.430 ac I I 1 I 1 1 I 1 I I I I 1 I I In 1 1 I I I I I I I 13� 1 1 I I - -t- -1 - 1 - Y - Y - t - t - t - t - r - r RunofVolume l ,0-5' at I I I I 1 I I 1 I I I I I I I Ili ' I I I I I I ■I � 12-z_ I I I - -1- -y- -,- '� - -j - -j - T - j - T - 1- - ,' - r - r - r -I- -I- '7� - 11 _ I I I I I I I , , , , m ,1 I 1 I 1 1 1 1 1 1 I �u Hoff Depths= .14 1 I I 1 1 1 1 1 1 1 1 1 1 1 1 1 I I 1 1 1 I 1 1 I I -- 1£ 10I_ _ I_ _I_ _1 I I 1 I I I _ 94 _ I _.1 _I - _I J J J 1 1 1 1 1 L L L L L I_ I_ 1 I I I 1 I 1 till 1 1 I 1 1 1 1 t ^ ry,' 8- -f- -t i - -I- -1- -1 - •'1 - ; - { - a - + - 1- - L - I - 1- - I- - I- -1- -I- -1 I - _1 - 1 - Tc=1 T T m i n I I I 1 I I I I I I I I I I 1 I 1 I I I I 7: 1 i I -I- -1- -1 - -1 - 1 - 1 - 1 - T - r - r - r - r - r - r -1- -1- -I- -I - -1 - -1 - -I I - -I - I - r^ j� I - I I I , I I I 1 I I I I I 1 I 1 11111111111 Y--P85 - 6= - ,- -,- -,- - -,- -I- -1 - 1 - 1 - 1 - 7 - 7 - 1 - 1 - 1' - I- - ,- - 1- -1- -1- -1- -1- -1- -1 - l - 1 - 1 - 1 - , 5_ I_ _I_ _I_ I 1 I IIIIIIII I I IIIII I It I I I I _ I I I 1_ I I II I I I I 1 1 I I 1 I I 11111 I II I 111111i 1 1 1 1 1 4= . 1 a I _I_ _1 _1 _ Jill 1. 1 L L L L L I_ I I I I I J J J J 1 1 1 1 L 1 I 11111111111 1 I 1 1 1 I 1 I II I 1 1 1 I 1 1 1 3- , - I- - I- -I- -I- I I I -I - J _ + - -4 - + - J. _ 4. - L. _ I- _ I- - 1- 1 1 II I I I -1 4 4 + 4 4- 4- I- - III IIIIIIIIIII I 1 1 1 1 1 1 I II I I I I I I 1 I 2 - I II - -I- -1 - 1 - 1 - 1 - 'f - t - t - r - r - r - r - h -I- -I- -I- -1- -I -I - -1 - 1 - -I - 1 - t - t III I I _ 1 1 1 1 1 1 1 1 1 1 1 I , II I IIIIII t o_ �d 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 42 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant_Proposed Conditions Type II 24-hr 5-year Rainfall=2. 20" • Prepared by {enter your company name here} Page 5 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Subcatchment 2S : POB2 Runoff = 2.94 cfs @ 12.01 hrs, Volume= 0. 181 af, Depth= 1 .97" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs. dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.20" Area (ac; CN Description 1 . 100 98 Pasture/grassland/range, Fair, HSG B 1 . 100 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1 .6 100 0.0240 1 .05 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 1 .6 225 0.0220 2.39 Shallow Concentrated Flow, Unpaved Kv= 16. 1 fps 1 .2 205 0.0050 2.80 19.57 TrapNee/Rect Channel Flow, Bot.W=4.00' D=1 .00' Z= 3.0 '/' Top.W= 10.00' n= 0.029 4.4 530 Total, Increased to minimum Tc = 10.0 min Subcatchment 2S : POB2 • Hydrograph I I I I I I I I I I I I I I I I I I I I I I I I I r I I I I I I I I I I I I I I I I , fill I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I p Runoff 2.94 cfs , 1 1 I I 1 1 I I ; J J _ i t 3 I 1 I I ( I I I 1 I I I I I I I I I I I I I I Type; III 24-h r 5-year I I I I 1 1 1I 1 1 1 I 1 I I I 1 I 1 1 I I I I I R a i n f a l l=2 .2 0" I I I I I 1 1 I I I I I I I 1 1 I I 1 1 I I t I I I I I I 1 I I I I I I 1 1 I I I I I ' ' ' ' ' ' ' ' ' Runoff Ara=1 . 100 ac I 1 I 1 I I 1 I 1 1 I I I I 1 I I I I M I ( I 1 I I I I I 1 I 1 I I Runoff I I r _I I t � i - L _ L - I- -I- -I- I I I I 2 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; twicifiVolume=0 . 181 if 1 I I I I I I I 1 I I I I I I I I I I I I I 1 � � � � RunoffDepth=1 .97" I I I I I I 1 I I 1 I I I I I I I I I I ' ' ' ' ' Flow Length=530' I I I I 1 I I I I 1 I 1 1 I 1 1 I 1 I I I I I I I 1 1 I I I I 1 I 1 I 1 I I I I I I jT M I I I I I I I I I I I 1 I I 1 I I 1 I I I I 1 c= 1 0.0 _ I y I -1 7 4 Y 1- r r r r 1 1 1 , 1 t -1 l - l - It Y _Z- - 11 I 1 1 1 1 1 I I 1 I 1 I 1 1 I 1 1 1 1 I 11 I I1 I I AI I I 1 I 1 1 I I I I 1 I 1 1 I I 1 I I 1 1 I al 9 I I - t I I I I I I I 1 I I 1 I I I 1 t I I I I 1 I I r 11 I 1 I 1 1 1 I 1 I 11 I 1 1 I 1 I 1 1 I 11 I I I I III 11 1 I 1 1 1 1 1 I 1 I 11 1 1 I I 1 1 1 1 I 11 I I I I lit 1 1 I 1 1 1 1 1 I 1 I II I 1 1 I 1 I 1 1 I 11 I I I I III 1 I I 1 1 1 1 1 I I I II I 1 I 1 1 1 1 1 1 11 I I I I III I I I 1 1 1 1 1 I 1 I 11 I 1 I 1 1 1 1 1 I II I I I I III I I I Milli ! I I I I till I I I I I 1 I 1 1 t I 1 I IIIII I I I II I I I I I I I I I II I I I I 1 1 I 1 ( I 1 I I 1 II I I I I I I I I I I I I I I 1 I I I 0- . 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 43 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant Proposed Conditions Type l/ 24-hr 5-year Rainfall=2. 20" IIPrepared by {enter your company name here} Page 6 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Subcatchment 3S : POB3 Runoff = 0.04 cfs @ 12.02 hrs, Volume= 0.002 af, Depth= 1 . 13" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs. dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.2011 Area (ac) CN Description 0.024 88 Pasture/grassland/range, Fair, HSG B 0.024 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) ;ft/sec) (cfs) 2.7 450 0.0290 2.74 Shallow Concentrated Flow, Unpaved Kv= 16. 1 fps 0.6 100 0.0290 2.74 Shallow Concentrated Flow, Unpaved Kv= 16. 1 fps 3.3 550 Total, Increased to minimum Tc = 10.0 min Subcatchment 3S : POB3 Hydrograph / II . I p i I I I I I I I I I i i i I I I I I I i , _I_ _1_ _I I . _1 1 .. 1 _ L L I I I J J 1 L L I I I I I I I L I I I I I I I I• I I -- - I 1 1 I I I I I 1 I I I I 1 I I I I I I I I I 1 I I I I ❑ Runoff 0-044= - I' - - + -+- -+- -1- I _ 1 _ + _ 1- _ L - F -+ +- + + + I + + I ' I' +- + + - + + __ I 0.04 cfs I I I I I I I I I I I I I I I I I 0.042= - , r - r r 1 I t i -t r r r r l I 0.04_ 1 IIIIIIIIIIIIII 1 1 I 111111111111111 0.038- ._I_ _I 1 _ 1 _ L _ L _ I_ _I_ J_ J _ J _ 1 _ 1 _ L _ L _I_ -I._ J I_ L I .II "0.036; -I- -I t - t - h - I- - I- -I- -I- 1 - 1 - t - t - I- - F- -I - -1- -1 - 1 - 1 I Rainfall=2 .20" 0.034- I I I IIIIIIIIIIIIIIIIII 1 -r -I- -I I T r t , 1 I 1 1 r T r r I .. f 0.0302- _L _I_ _i i _ _ i _ L _'- -�- �- - - _ - - L -l_ _Ft doff Area=0.024 ad 0.03' - -H -I- -I - + - t - F - h- -1- -I- -I- i - i - t - i- - 1- - F I - -I - f��/�I r - 1- 0.028' I I I I I 1 I I 1 1111111 Ruln.01 -�- 0.002-n�e= .002- af - -I - - -1 1 1 r 1 1 1 1 i 1 T T r 1 1 , tq 0.026- -t- _I_ -I _ IILII I I I I I I I I I I I , ,Q V I I I IIIII I IIIIIIIII - tRunoff Depth= 1 . 13" 0.024= I I I - + - + + 1- -+- + - + -I - + - 4 - I- - +- -+- i I I I I I 1 I , I 1 1 I 1 1 1 1 1 , I 0 0.022= -r -1- -1 - r r r r l 1 1 I i r r r r 1 , -1 Flow Length-:550'IL 0.02- I- -1- -I- -I- IIIII I I I I I I 1 I I I I . I 1 I 11111 I 11111111111 ii 0.018- _ L_ _1 -I 1 1 1_ L 1_ I I J J 1 1 L I- 1 1- -1 - --1 - 1 t_ 1_ 0.016= , -' - r - r - r - r - 1 - 1 - ? - r - r - r- - -i - 1 - SIOpe=0.0290 '/' 0.014- IIIII I IIIIIIIIIIII I I IIIII I I 1 I I I I I I I I I I I I I C= 1 0 0 . min 0.012- ' 1 _ 1 L I 1 I I J J 1 1 L L I I J J 1 1 1 It c= 10.0 1 I ' IIIII I I I I I I I I I I I I I I I I I 1 I I , 0.01" - t - + - fr - I- -I- -1- -I - 1 - 1 - t - t - f - I- -I- -I- -1 - H - i - i - t - h - I- - I- CN=88 0.0087 - - _ 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ... I I I I , I I I 1 I I I I I I I I - I I I r 1 I I I I I 0.006= 1 _ 1 L L I I I JJ _ 1 _ 1 _ L _ L _I -1 J J J 1 L L L _. I.. _I_ _I . ! _ J1 _ 1 I 1 I 1 I I I I I I I I 1 I I I I 1 I I 1 1 1 I 1 1 1 I 1 0.0047 . - ✓• - 1- - 1- - 1- -1- -1 - -4 - 4 - + - I- - 1- - 1- -1- -1- --1 - --1 -1 -1-- 1- - 4- 1- - 1 I - -1- --I - -I -1 - + ' ! I t I , 1 I 1 I i I I I ' IIIIII III 0.002-E __o.r 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 44 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant_Proposed Conditions Type ll 24-hr 5-year Rainfall=2. 20" • Prepared by {enter your company name here} Page 7 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Subcatchment 4S : POB4 Runoff = 0.89 cfs @ 12.02 hrs, Volume= 0.049 af, Depth= 1 . 13" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 5-year Rainfall=2.20" Area (ac) CN Description 0.520 88 Urban industrial, 72% imp, HSG B 0. 146 Pervious Area 0.374 Impervious Area Tc Length Slope Velocity Capacity Description (min; (feet) (ft/ft) (ft/sec) (cfs) 1 .9 100 0.0162 0.89 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 0.6 139 0.0162 3.97 11 .90 TrapNee/Rect Channel Flow, Bot.W=0.00' D=1 .00' Z= 3.0 '/' Top.W=6.00' n= 0.029 2.5 239 Total, Increased to minimum Tc = 10.0 min Subcatchment 4S : POB4 Hydrograph • -/ I- I I I I I I 1 1 1 1 1 I 1 1 t I I I I 1 I 1 I 1 I I I I 1 I I I I I I I I I I 1 I I 1 I I 1 I I I I I 1 I 1 1 I 1 I I 1 1 I I I I I I I 1 I 0 Runoff` 0.95= 0.89 cfs I I I 0.9' I 24-hr Type It 5-year - 0.85= _ I _'_ -'- - _ 1 I I I I I I 1 I 1 1 1 1 1 1 I IIII I I II II I II I II I II 1 I I 0.8- I_ Jr Rainfall-2 .20" I I I I I I 1 I t I I I 1 I I I I I I I 0.75 I I I 1 1 1 L L L L I_ I_ 3_ J _ J _ 1 _ 1 _ 1 L _ L _ I_ _ I I0.7- I 1 I I 1 LI L L L L I I J 1 1 1 lRuhoff-Area-0.520 ad - , I I I I I I I I I I I I 1 I 1 I I I I I I I 0.65-t, i i L L ,_ II I J I i Kilnoff %altime=0:0149= a ^ I I I • I I I I I I I I I I I I I I I I 0.55= IV I III I Runoff Depth=1 .1-3" 3 0.5 y -L I I -1 1 L 1- I- I_ II I -I a 4 } _ L _ !- _ , , _ // 1 I I I I I I I I I I I I I I I I l 1 I4" FIow ' Leflgth-239' _ (- _1- -I- 1 - -1 _ .1 _ L - 1- - l- -� I I I -! J 1 -i 4 - L I I I I I 1 I I I I I I 1 I I 1 I 1 I I I - 1 1 I 111111 I I I I I 1 1 I I I I I Slope-�,g162 ,_'/' 0.35 t- -I- -1- — r — t — t — r — r — r — — 1 —I - 1 — + - 1 — + — a — t — t - 1. 1 1 1 1 1 1 I IIIIIIIIIII I lit - 1 - Y - -t - r -- r - r - r 1 I I -1 -, -t - t - Y - Y - Y -I- T/�-10 0 min - 0.25 I I I IIIIII I I 1 I I 1 I 1 I I I I I 1 ■ i�I� 1- -I- -I- - + - + - - h - M - t- - 1- -I- -1- -I- -I - i - i - l - r - r - r - F- -I- -F- -I- i - -t - . 1 I I t 1 1 1 1 I I I I 1 1 I CN -88 - 7 - I - -I - r - r - I - 1- -I- -I- -I - -I - 't - I - -1 - r - I - I - I- I I I I Iy - +� I 1 1 1 1 I 1 I 1 I I I I I t 1 1 1 I I I I 1 1 t 1 I I r -I- -I - l - -t T r r r 1 I I , - , , i r r r r 1 t 1 1 -1 t r III 1 I 1 I I 1 I I 1 I I 1 I I I 1 1 I I I 1 1 1 1 1 1 I I I 0.1 I I I - -T - T - r - r - I I I I I _ , - -1 1 - f - r - r r r -r I - -I 1 1 - T 0.05- I I I I I I I I I 1 I I I 1 I I I I I I I I I I I I 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 45 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant_Proposed Conditions Type II 24-hr 5-year Rainfall=2.20" • Prepared by {enter your company name here} Page 8 HydroCAD®5.00 s/n 004197 ©2006 HydroCAD Software Solutions LLC 5/23/2011 Pond 5P: Detention Basin Inflow Area = 15.050 ac, Inflow Depth = 1.03" for 5-year event Inflow = 22.98 cfs @ 12.02 hrs, Volume= 1.287 af Outflow = 2.57 cfs @ 12.54 hrs, Volume= 0.985 af, Atten= 89%, Lag= 31.5 min Primary = 2.57 cfs @ 12.54 hrs, Volume= 0.985 af Secondary = 0.00 cfs @ 1.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 1.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 4,792.18' @ 12.54 hrs Surf.Area= 0.339 ac Storage= 0.641 af Plug-Flow detention time= 305.4 min calculated for 0.984 af(76% of inflow) Center-of-Mass det. time= 213.4 min ( 1,046.3- 832.9 ) Volume Invert Avail.Storage Storage Description #1 4,790.00' 1.785 af Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) 4,790.00 0.250 0.000 0.000 4,791.00 0.290 0.270 0.270 4,792.00 0.330 0.310 0.580 4,793.00 0.380 0.355 0.935 • 4,794.00 0.420 0.400 1.335 4,795.00 0.480 0.450 1.785 Device Routing Invert Outlet Devices #1 Primary 4,791.10' 8.0"Vert. Orifice/Grate C= 0.600 #2 Primary 4,791.75' 24.0"Vert. Orifice/Grate C= 0.600 #3 Secondary 4,794.50' 10.0' long x 0.50' rise Sharp-Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height primary OutFlow Max=2.57 cfs @ 12.54 hrs HW=4,792.18' (Free Discharge) 1=Orifice/Grate (Orifice Controls 1.45 cfs @ 4.16 fps) 2=Orifice/Grate (Orifice Controls 1.11 cfs @ 2.24 fps) Secondary OutFlow Max=0.00 cfs @ 1.00 hrs HW=4,790.00' (Free Discharge) 3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) • Page 46 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant Proposed Conditions Type II 24-hr 5-year Rainfall=2. 20" IllPrepared by {enter your company name here} Page 9 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Pond 5P: Detention Basin Hydrograph I I I I I I I , I I I t I I I I I I I I I I 1 I I I I I - .y 1- -I' -1 - + _ I- .I - , - I_ _I 1 - + - I- -I - 4 - F -1-- -I - + - {- --1 - 4 - 1- -- I- -I - 4 ■ Inflow 22.98 cfs 1 I I 1 I I I I , I I I I I I I I I I I I I I I I I I ❑ outflow Inflow Area= 15.050 a D Primary _. ,, Secondary 24- I_ I . • , , In; _; Peak Elev=4,792 .1 $' 22- I , I 1 I I I I Storage=0.641 al 20- I I 1 I 1 1 I 1 I I I 1 I I 1 I I 1_ - J I_ _I I _ L _ ,_ J I I. _I _ I I I. -I 1 L I . I t . I I_ 18- I I I 1 I I I I I I I I I I , , I t I I I I I I I I I 1 I I I I I I I I I I 1 I I I I 1 I I I I I I I I I J- - I-- I , I I , 1 I ..I 1 -_ F- _. , .,. - t_ ..I - .i - I- 16- I I I I I I I I I I I I I 1 I I I I I I I I I I I I I ^ I , 1 I I I I I I I , I I I I I I I I I I I I I I I V) _ J- '- i -1 -- _1 - 1- --I - i I I I I 1- I -1 - .. .. I. .I .I , , ( I I -- -- i- _I - .l. O 14- I I I I I , I , I I I I I I , I , I I I I I I , I I L _ ,- I I I I _ 1 - l _ I- .I -_ 1 _. I. _I -. .! I_ I J _ 1. I I I- ' J I_ - I - 3 - I I I I I I I I I I I I I I I I I I I I I I 1 I I o 12 G - I I I I I I I I I I I I I ! I I I I I I I I 1 I 1' "' 1- '_t .i .. r. _I - '1 F- 1 ?- -I- _I • - I- -I -- 1 I- I ! i t , , I -1 -. • 10- I I I I 1 I I I I I I I , I I I I I 1 t 1 I I t I I I I I I I 1 I I I I I I I I I I I ( I f ; , I 1 i I I I I. I I J I I I I- - I" 8-:. 1 , I , t I t I 1 I I I I I , I I 1 I I I I I 9 R7 rf I I - -- _t_ ,. I - _ - I- t i l_ I I I I I I I I I I I I I I I I I I I I I I I I I I I I I s- 2.57 cfs , I I I , I I 4 /1II , �1% / 0.00 cfs ~ f///1�/!l//////%%r////i/// ///// - ////////////i _ ► vA 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 III Time (hours) • Page 47 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B • La Salle Gas Plant_Proposed Conditions Type 1124-hr 100-year Rainfall=3.80" Prepared by{enter your company name here} Page 10 HydroCAD®8.00 s/n 004197 ©2006 HydroCAD Software Solutions LLC 5/23/2011 Time span=1.00-72.00 hrs, dt=0.05 hrs, 1421 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: POB1 Runoff Area=13.430 ac Runoff Depth=2.28" Flow Length=1,075' Tc=10.0 min CN=85 Runoff=46.02 cfs 2.552 af Subcatchment 2S: POB2 Runoff Area=1.100 ac Runoff Depth=3.57" Flow Length=530' Tc=10.0 min CN=98 Runoff=5.15 cfs 0.327 of Subcatchment 3S: POB3 Runoff Area=0.024 ac Runoff Depth=2.54" Flow Length=550' Slope=0.0290'/' Tc=10.0 min CN=88 Runoff=0.09 cfs 0.005 af Subcatchment 4S: POB4 Runoff Area=0.520 ac Runoff Depth=2.54" Flow Length=239' Slope=0.0162 'P Tc=10.0 min CN=88 Runoff=1.96 cfs 0.110 af Pond 5P: Detention Basin Peak Elev=4,793.84' Storage=1.269 af Inflow=53.13 cfs 2.989 af Primary=18.42 cfs 2.686 af Secondary=0.00 cfs 0.000 of Outflow=18.42 cfs 2.686 of Total Runoff Area= 15.074 ac Runoff Volume= 2.994 of Average Runoff Depth = 2.38" 90.22% Pervious Area = 13.600 ac 9.78% Impervious Area = 1.474 ac • • Page 48 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant Proposed Conditions Type II 24-hr 100-year Rainfall=3. 80" • Prepared by {enter your company name here} Page 11 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Subcatchment 1S : POB1 Runoff = 46.02 cfs @ 12.01 hrs, Volume= 2.552 af, Depth= 2.28" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80" Area (ac) CN Description 13.430 85 Pasture/grassland/range, Fair, HSG B 13.430 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1 .5 100 0.0300 1 . 14 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 2.4 975 0.0180 6.80 96.89 TrapNee/Rect Channel Flow, Bot.W=5.00' D= 1 .50' Z= 3.0 '/' Top.W=14.00' n= 0.029 3.9 1 ,075 Total , Increased to minimum Tc = 10.0 min Subcatchment 1S : POB1 Hydrograph / 1 I I I I I I I I I I I I , i i I I , , , , • I- -t- I I I 1 1 -1 - -I -I - 1 - 1 - t - t - r - I- - r - r - t- - r -I- - r - r - f' - 50= -'I I I I I I I I I I I I i , I i I .. ,. -I I I I j_ L II . Runoff 45 46.02 cfsIII - - - - - ; - - - - � - - � � - ;. 46- I- -I- _1- - - -I- -I - -i - -I - -1 - + - + - + - + - t- - r - I- - r - 1- -I--`-p Ja =al-_ht- � Ojyear I I , , I 1 I I I I I I I I I I I 44 42- I 1 1 , I I I 1 1 , I I 1 I I I 1 I , I I I I _ , I , I 40= -;- -I- -I- - - -I- -I- -, - - - 4 - ; - + - 4- - 4- - I- - 4- - t- - I- - ; ' -I- -1-111111 Rainfall=3.80., I , , t I I , , I , 1 , 1 1 , I , 1 I I , 38; _;- _;_ _;_ _ - -1 - ;_ -; _ -1 _ 4 _ 4 _ 4. - 4. _ 4- - 4- - 4. _ 4- - 4. - I. Runoff Area=13.430 -ad - 36 1 I , I I , , I I 1 , I 1 1 , I I 34'; -I-M-I-- ii 1 I I 1 , t I I I 1 i - - 32.; I I I -I -1 J -J -1 -L 1 4 I 4- I- I- ' Runoff Volume=2 .552 2 .5 5 2 af - 1 1 , I I , I I , 1 I I I I I I 30-E j 1 -I- - II I I I I I I I I I I I 45 28_ - _ _ _,_ ' - I - ; - ; _,_ _;_ Runoff Depth=2.28" 26- -j -I -,- - I 1 , , , I I I , I 1 t , II 1 ..I , I O 22- - I- `,- _I_ _ - -1- -1- -t - - - -1 - + - 1 1• - 1- - 1 1- - /- - I- -I- -1- Flow I .ength�-=' ,OT5'_ 1 I I 1 I I I I I I I I I I t I I I 1 I e , I -I- -1 -I- - -1 - -I - -1 - -1 - 7 - 7 - T - T - r - r - r - 1- - r - I- -1 I , , I I , , I I , 20_ I I I 1 - -I- .J _ J _ J _ 4 .1 1 1 l I- L 1_ I- I- 1 I I I I -J L _ 1/25 - 1-18i / ill ' lititiiiiiti ii ii r 1- -I- -1- -I- - -1_ -1 -1 -1 d 4 4 1 1 4- L I- I- I- I_ I- I- I- I- _I - , _ 4 _ a 44 /A, , 1. ' , I 1 I 1 1 1 1 1 1 1 1 1 1 1 1 I II 1 II I I I 1 1 , CN�85 14= rr 1 t 1 , I 1 1 T T T T T r r r r r 1 I II I , I 1 1 7 (�J 12= I_ _L _I_ _,_ _I _I J J J. 1 J. 1 1 1 1.. L L L I_ I 1 I I J J J J J 1 _ i _ i _ 1_ _ , I I 1 I I 1 I I I I I I I I I I II I II I I I MIMI 10- I I I I I I 1 1 1 7 1 T T r r r r r I I II I 1 1 1 1 1 T r r TI 8_ -I- _,- _I_ _I J J J 4 1 1 1 L 1 1- 4- I_ I- I- I I I I I -I J 4 J 1 4. 1. 1. L I 1 I I I I I I I I I I I I I I I II I II I I I IIIIIIII 6- '` r -I- -1- -I- -I_ `I- -I - -I - "1 ` TT - T - r - r - r r r I 1 I II t -1 -1 1 -I 11-1- T r r 4y I I_ _I_ I -. _ _I - _I . _1 _ 1 _ 1 _ l _ 1 - 1 I. _ I. _ L _ L _ 1_ _1_ I I I I 1 I J l _ J _ 1 _ L _ L _ I II 1 , I I I 1 I I I I I I I I I I i , , I , 2- 0 - 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 49 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant_Proposed Conditions Type II 24-hr 100-year Rainfall=3. 80" IllPrepared by {enter your company name here} Page 12 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Subcatchment 2S : POB2 Runoff = 5. 15 cfs @ 12.01 hrs, Volume= 0.327 af, Depth= 3.57" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80" Area (ac) CN Description 1 . 100 98 Pasture/grassland/range, Fair, HSG B 1 . 100 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet', (ft/ft) (ft/sec: (cfs) 1 .6 100 0.0240 1 .05 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 1 .6 225 0.0220 2.39 Shallow Concentrated Flow, Unpaved Kv= 16. 1 fps 1 .2 205 0.0050 2.80 19.57 Trap/Vee/Rect Channel Flow, Bot.W=4.00' D=1 .00' Z= 3.0 'P Top.W= 10.00' n= 0.029 4.4 530 Total , Increased to minimum Tc = 10.0 min Subcatchment 2S : POB2 • Hydrograph I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I II I II I II I I III II I I IIII I I I II I II 1 II I I I I I I I I I I I El Runoff t 5. 15cfs illi _ _ _ _,- -,_ _ Type 1r - r100-year 5 I I I HI I I I I I I I I I I I I 1 I Ra l n f a l l 3.8 0" I I I I 1 I I I I I I I I 1 I I I I I I I I I I I I 1 I 1 1 1 1 I I I 1 1 1 I I I 1 I I I I I ill I Ir - - -I- - - -I 1 - 1 - I - I - -1 - I - I -- I - I - I - 1 I I- I I I Rhjll-O#f Ai' a-1 . 1 00 ac 4 I I I I 1 I 1 1 I I 1 I I 1 I I I I I I Rur�Qf , volume=0.3'2? A1 1 I I I I I I 1 I I I I 1 1 I I 1.1. I I I I I 1 I 1 1 I I I I I I I I 1 1 I I I I I 3 -;- -,- - ;mil i i ; ; ; ; , Rufoff;Depth=3.57' � , ; II I iii II I I 11 II I I 1J 1 L L L L L I_ I_ J _ _I _ 1 _ 1 _ 1 r♦,� *On I I e 1 I I 1 1 I I I 1 II t 1 I I I I 1 I I I 'C=1 O. T 2 I I 1 I 1 1 I I I I 1 1 1 I I I I I I 1 I 1 I I I t 1 I I 1 I I 1 I I I I I I I I I IIIIIII I I I 1 ' I g� I I I 1 1 1 I I 1 1 I I I I I I I 1 I I 1 I I I I I I 1 1 _ _ _ _ �, �I _ _I _ _ _ _ _ .: _ :. _ „ _ , _ F _ ,_ _I_ _1_ _1_ _,_ _I_ _1 _ .{ _ -I _ .1 _ -I _ i. _ F _ }- _ F _ I_ _ N _ I- _I_ -1_ _ 1 1 I I 11111 1 I 1 II I I I I IIIIIII I I I IIII I I I I t I 1 I 1 I 1 I I 1 I 1 1 IIIIIII I I I 1 1 I 1 I I I I 11111 I I I II I I I I 1111111 I I I 1 I 1 1 I 1 I I IIIII I I I II I I IIIIIIIII I I 1 1 1 1 1 1 I t 1 IIIII 1 I I II I I IIIIIIIII I IIIIII I I -A I I I I I I I I I I I I I I I III I I I I I I I 0 - S----- 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 50 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant Proposed Conditions Type II 24-hr 100-year Rainfall=3. 80" • Prepared by {enter your company name here} Page 13 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Subcatchment 3S : POB3 Runoff = 0.09 cfs @ 12.01 hrs, Volume= 0.005 af, Depth= 2.54" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs. dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80" Area (ac; CN Description 0.024 88 Pasture/grassland/range, Fair, HSG B 0.024 Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.7 450 0.0290 2.74 Shallow Concentrated Flow, Unpaved Kv= 16. 1 fps 0.6 100 0.0290 2.74 Shallow Concentrated Flow, Unpaved Kv= 16. 1 fps 3.3 550 Total, Increased to minimum Tc = 10.0 min Subcatchment 3S : POB3 Hydrograph 1 1 _ 1 _ L _ L _ I. _ 1 _ 1 _ 1 joe I I I 1111 I I I I • 0.1 ,» L _1_ .. 1 _ L L L I I I I .J J J. 1 1 L L 1 I 1 I J J 1 1 1 L L I _ . Runoff 0.0955 " ,. � _L. 0.09 cfs 1 L L L L L. I- J- J _ J _ 1 . I I _ L - L -L _ I - - L - I _. _I _ I 1 _ J _ L _ L _ L _ L _ : , , I I 1 1 I I I I I 1 I I I I Thè I I1 1- , I I I I I I 1 1 1 I 1 1 1 I I I I lil _ r 00�y;e�rr, - 0.085- . 1- -I- -I- -I - - • - + - + - 1- - 1- - I- - 1- -I- -I- -I- -I- -/ - i - 4-I--II! - I I I - 1- - f- - F - ,- - 008= I I t t - t - t - I- - 1- - I - 1 � Y � f - t 1 Rainfalh=3• - , - ' I I I I IIIII I I I I I I I I I I I I I I I r r I r I III 0.075: O I I _ 0.07 - li - Y - r - r - r - ; - ; - T - 1u b_ff .Akea-0 .021A0'- - } r I 0.065- . ' I I I I I I I I I I I I I I I I 1 'off I I I ' I I I I I 1 r I_ 1 I I I 1 I 1 I uno v'O;lme 0 .005 af- - , 0.06= , ' " I I I I III II I I I 1 II 1 _ i - i _ i I , . I I - w 0.055= I I I 1 id 1 1 1 1 1 I 1 I I I I I I I i - , ' - � - I- 1 I IIIII I I 1 I I 1 ; ; ; - Runoff Depth-2 .54„ 0.05: ' - 1- _ - -I_ 1_ IIIIII I I I I III _ I _ i _ I • I ° I I I I ' ' I II I I I ' II ' ' ' I Flow Length-550' 0.045- • , I I I - I I I I I 1 ii _I - -' - ' - ' - ' I _ ' _ I - : , ' I 1 1 I I I I 1 1 , 1 I I I mill I ii 0.044 ' I- - I- -.1._ _.I _. - 1 _ l _ L _ L _ L _ L _l_ _I_ J_ J_ J _ .l _ 1 - L _ L _ L _L I I : I I I I 1 1 1 1 I 1 1 1 I I 1 I 1 I I 1 1 I 0.035 . L _ I_ _ I- -I - J 1 L L L I- I I I I 1 1 1 1 L L L. Slop 9Q '/I = , I 1 I I I I I I I 1 I I I 1111111 I IIII 0.03 . I- -- I - I I _ J 1 L 1- I- I- II I I -1 4 1 1- L I_ I- I- I- Tc-10 0 -m■n- - 1 I II i fill ( 1 II I 1 I I I I 1 I 1 1 1 0.0257 � - I- - I- --I._ ,.I - .- + - + - 4- - I- - 1- - 1- -I- -I- -1- -1- -I - 1 - 1 - 4' - F - I" - I- -I- -1- -I - -I - 1 - ,. _ y. _ 1- , I I I 1/ IIIIIIII I I I I I 1 I I I 1 1 1 I I C N i-88 0.027 , - I-- - I- - I-- - -1 - + - ♦- - N - 1- -I- -1- -1- --I - -1 - - -1 - + - - H - F - F- -I- -I- -1- -1- -1 - + I� „ I II '/ I I I 1 I 1 1 1 1 IIIIIII I IIIIIIIIIII 0.0157 . - I- - I- -- I- I - t - t - r - r - r -I- -r I 'I - -1 - t - t - t - r - r - r - r 1 1 I -I- 7 - t - T - 1- - r - r - I 0.01� ' III ,/ I I I I I I I I I I 1 1 1 1 1 1 1 1 III 1 1 1 1 1 1 1 I , -, -I T r r r r I I I- -1- 1 - 1 - 1 - r - r - r -I' / 0.005- ' I I I I ' rid, I I I I I IIIIIII I IIIIIIIIIII 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 51 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant_Proposed Conditions Type ll 24-hr 100-year Rainfall=3. 80" • Prepared by {enter your company name here} Page 14 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Subcatchment 4S : POB4 Runoff = 1 .96 cfs @ 12.01 hrs, Volume= 0. 110 af, Depth= 2.54" Runoff by SCS TR-20 method, UH=SCS, Time Span= 1 .00-72.00 hrs, dt= 0.05 hrs Type II 24-hr 100-year Rainfall=3.80" Area (ac) CN Description 0. 520 88 Urban industrial, 72% imp, HSG B 0. 146 Pervious Area 0.374 Impervious Area Tc Length Slope Velocity Capacity Description :min) (feet; (ft/ft) (ft/sec) (cfs) 1 .9 100 0.0162 0.89 Sheet Flow, Smooth surfaces n= 0.011 P2= 1 .60" 0.6 139 0.0162 3.97 11 .90 Trap/Vee/Rect Channel Flow, Bot.W=0.00' D=1 .00' Z= 3.0 '/' Top.W=6.00' n= 0.029 2.5 239 Total , Increased to minimum Tc = 10.0 min Subcatchment 4S : POB4 Hydrograph • / I I I I I I I IIII I I TII II II I 1 1 1 1 1 1 1 1 1 1 I 1 I I I I I I I 11111111111111 `L■ I I I I I I I I I , I I I I I I I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ❑ Runoff I 1 .96 cfs J _ J _ 1 _ !. _ L _ L _ L _ I_ _l_ _1_- IIJIILLLLI_ 1_ I_ I IIII I IIII I I I I I I I I I I I I I I I I I 2 I I I till l I I I I I I I I I I I I 1 1 I I I I I I I I I I I I I 1 I Type lI 24-hr 1 00-year I I I I 1 1 1 1 1 I I I II I I I 77 1 1 1 I I 1 I I I 1 I II I I I I till 1 ' I R a i n f a l l=3 .8 0" I I I IIIII I 1 I 1 1 I 1 1 I IIII I 1 I 1 1 1 1 1 1 I I 1 II 1 t I I 1 1 1 1 1 1 1 1 1 l l Rtinoff A'raa=0 .520 ad I 1 I 1 1 1 1 1 I I I II I I 1 I IIII il I 1 1 1 I 1 , 1 1 1 1 1 I I 1 1 1 I 1 1 I I 1 I I I I I 1 I I I I I �tur�off' Volkir a 0: 111 b if I I _ I I I I I I I I I I I I I I I I r I I I I I I I I I I I 1 I I i I 1I U I I I I I I I I I I I I I I ' ' I Runoff iDepth=2.5'T" I I 1 I I 1 I 1 I I I I I I I I 1 1 1 _I_ _ 1_ _I - - 1 _ i _ -4 _ 4 _ 4 _ 3- _ } - f- _ I- _ I- _I_ _1_ _I_ _I_ _I_ _I -- III 3 11 I 11111 LL 1 I I 1 ' I I 1 I I' 'I Flow Length:=239' 239' 1- 1 I I I I I I I I I I I I I 1 I 1 I I I 1 1 1 1 1 1 I I I II I II I II II I I I. 1 I � � I I I II a I I S I Q pe=4 .0' 6 ; '/' I I I I IIII I I I II I I I I I I 1 I I I I I I I I I I I I 1 I I I 1 I 1 II I I I I I I I I I I tc-1 0 Y Min'I I I I 1 I 1 I I I I II I I I I 1 1 1 1 I I I r ■ I I I 1 1 l 1 I I I II I I I I I I , I I I I I 1 I I I I I IIII 1 1 I II I I I I I I 1 I I I I I C N 8 8 1 I I I I I I I 1 I I II I I I I 1 I I I 1 1 1 I - 1 I I I I IIII 1 I I II I I I I IIII I IIIIIIIII 1 I I I 1111 I • 1 I II I I I I lilt I IIIIIIIII I 1 I I I IIII I I I II I I I I IIII I 111111111 1 I I 1111 1 I 1 II I I I I IIII I 111111111 I I Iiis I I I I II 1 I 1 I 1111 I IIIIIIIII r 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) • Page 52 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant_Proposed Conditions Type 1124-hr 100-year Rainfall=3.80" . Prepared by {enter your company name here} Page 15 HydroCADO 8.00 s/n 004197 ©2006 HydroCAD Software Solutions LLC 5/23/2011 Pond 5P: Detention Basin Inflow Area = 15.050 ac, Inflow Depth = 2.38" for 100-year event Inflow = 53.13 cfs @ 12.01 hrs, Volume= 2.989 af Outflow = 18.42 cfs @ 12.18 hrs, Volume= 2.686 af, Atten= 65%, Lag= 10.2 min Primary = 18.42 cfs @ 12.18 hrs, Volume= 2.686 af Secondary = 0.00 cfs @ 1.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 1.00-72.00 hrs, dt= 0.05 hrs Peak Elev=4,793.84' @ 12.18 hrs Surf.Area= 0.414 ac Storage= 1.269 af Plug-Flow detention time= 168.8 min calculated for 2.684 af(90% of inflow) Center-of-Mass det. time= 118.8 min ( 930.4- 811.6 ) Volume Invert Avail.Storage Storage Description #1 4,790.00' 1.785 af Custom Stage Data(Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) 4,790.00 0.250 0.000 0.000 4,791.00 0.290 0.270 0.270 4,792.00 0.330 0.310 0.580 4,793.00 0.380 0.355 0.935 • 4,794.00 0.420 0.400 1.335 4,795.00 0.480 0.450 1.785 Device Routing Invert Outlet Devices #1 Primary 4,791.10' 8.0"Vert. Orifice/Grate C= 0.600 #2 Primary 4,791.75' 24.0"Vert. Orifice/Grate C= 0.600 #3 Secondary 4,794.50' 10.0' long x 0.50' rise Sharp-Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height rimary OutFlow Max=18.37 cfs @ 12.18 hrs HW=4,793.84' (Free Discharge) 1=Orifice/Grate (Orifice Controls 2.61 cfs @ 7.46 fps) 2=Orifice/Grate (Orifice Controls 15.76 cfs @ 5.02 fps) Secondary OutFlow Max=0.00 cfs @ 1.00 hrs HW=4,790.00' (Free Discharge) 3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) • Page 53 of 54 La Salle Gas Plant Draingae Report HydroCAD Proposed Conditions Appendix B La Salle Gas Plant Proposed Conditions Type Il 24-hr 100-year Rainfall=3. 80" illPrepared by {enter your company name here} Page 16 HydroCAD® 8.00 s/n 004197 © 2006 HydroCAD Software Solutions LLC 5/23/2011 Pond 5P: Detention Basin Hydrograph I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I , I I I , I I I I - - ,1 _ 1I I I , I I I I I I I I 1 1 , I I I I I , _ 1_ _ 1 _I , ■ Inflow 53. 13 cfs I I -I - I , I I I I I I I , I I I I I I , I ❑ outflow I-- ! _ ,_ _1_ , _ ■ Primary 1 1 . 1 1 , Inflow Area-15.050 ac, p Secondary , , I I I , , I I I I I I I I I 55- '_ _' - 1 I _ , i Peak EIev=4;;793.84'1 5°- , I 1 1 1 1 , 1 1 , Storage=1 .2!9 of I I I I I 1 I I I I I T T f l i - r- -I - i - f 45 I , , , I I , I I I I , I I I I I 1 , I , I I I I I I I I , I I I I I I I I , I I I 1 , 1 I 1 , 40 I I , .I - - , 1 , , 1 , 1 , , , - , - - - 771— (- - I I I I I I I I I , I I I t I I 1 I I I I 1 1 I I I I I I I I I l I I I 1 I ! I I • ! I I I I I —_ t I I .I _ i_ ' _ - I I I I , I I I I I 1 __ II - ' I_ I , I I I <n 35 _ 1 I I I I I I I I I I I I I I I I I I I I I I I I I 4- C.) - I I I I I , , I I I I I I I I I , , , I I - I I I I - 3 3°- I I I I I I I I 1 R 49 rf 1 , I I I I I I I I I I I I I I I I I I I I I I I I , 0 I I _ I _ I_ _, _ I I I I , - I- -'I -- I - I- -1 - -_I - ! - I - ' -- LT 25- 18.42 cfs , I 1 , , , I I I , I 1 I , , I , , I , , , , , I I I 1 , 1 , , I I I I I 1 I 1 . _I20 '�� I , I I 1 I I I I I I I I I I I I 1 I I I I I I ,%'J`� I I I I /mil/ ////% 0.00 cfs // �� r///r/////////////////////////////////////f/./////////�///� 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 IITime (hours) • Page 54 of 54 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Trapezoidal Channel - P081 Swale Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.029 Channel Slope 0.01800 ft/ft Left Side Slope 0.33 ft/ft(H:V) Right Side Slope 0.33 ft/ft(H:V) Bottom Wdth 6.00 ft Discharge 46.02 ft3/s Results Normal Depth 1.15 ft Flow Area 7.34 ft2 Wetted Perimeter 8.42 ft Top Width 6.76 ft Critical Depth 1.20 ft Critical Slope 0.01594 ft/ft Velocity 6.27 ft/s • Velocity Head 0.61 ft Specific Energy 1.76 ft Froude Number 1.06 Flow Type Supercritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 1.15 ft Critical Depth 1.20 ft Channel Slope 0.01800 ft/ft Critical Slope 0.01594 ft/ft • Bentley Systems,Inc. Haested Methods Solution Center Bentley FlowMaster [08.01.088.00] 6/11/2011 10:26:26 AM 27 Slemona Company Drive Suite 200 W Watertown,CT 06796 USA +1-203-766-1688 Page 1 of 1 Page 1 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Trapezoidal Channel- POB2 Swale Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.029 Channel Slope 0.00500 ft/ft Left Side Slope 0.33 ft/ft(H:V) Right Side Slope 0.33 ft/ft(H:V) Bottom Width 4.00 ft Discharge 5.20 ft3/s Results Normal Depth 0.57 ft Flow Area 2.40 ft2 Wetted Perimeter 5.21 ft Top Width 4.38 ft Critical Depth 0.37 ft Critical Slope 0.02019 ft/ft Velocity 2.16 ft/s • Velocity Head 0.07 ft Specific Energy 0.65 ft Froude Number 0.51 Flow Type Subcritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.57 ft Critical Depth 0.37 ft Channel Slope 0.00500 ft/ft Critical Slope 0.02019 ft/ft • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 6/11/2011 10:26:69 AM 27 Slemons Company Drive Suite TOO W Watertown,CT 06796 USA +1-203.766-1666 Page 1 of 1 Page 2 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Circular Pipe - 18 inch RCP Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.012 Channel Slope 0.00500 ft/ft Diameter 1.50 ft Discharge 5.20 ft'/s Results Normal Depth 0.88 ft Flow Area 1.07 ft' Wetted Perimeter 2.61 ft Top Wdth 1.48 ft Critical Depth 0.88 ft Percent Full 58.5 % Critical Slope 0.00499 ft/ft Velocity 4.84 fUs Velocity Head 0.36 ft • Specific Energy 1.24 ft Froude Number 1.00 Maximum Discharge 8.66 ft3/s Discharge Full 8.05 fN/s Slope Full 0.00209 fUft Flow Type SuperCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % Normal Depth Over Rise 58.52 % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster (08.01.088.00] 6/11/2011 10:29:30 AM 27 Siemons Company Drive Suite 200 W Watertown,CT 06796 USA +1203-766-1666 Page 1 of 2 Page 3 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Circular Pipe - 18 inch RCP GVF Output Data Normal Depth 0.88 ft Critical Depth 0.88 ft Channel Slope 0.00500 ft/ft Critical Slope 0.00499 ft/ft • • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster ]08.01.066.00] 611112011 10:29:30 AM 27 Siemons Company Drive Suite 200 W Watertown,CT 06796 USA +t-203-766-1666 Page 2 of 2 Page 4 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Circular Pipe - 12 inch HDPE POB4 Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.010 Channel Slope 0.02130 fUft Diameter 1.00 ft Discharge 0.96 ft'/s Results Normal Depth 0.25 ft Flow Area 0.16 ft' Wetted Perimeter 1.06 ft Top Wdth 0.87 ft Critical Depth 0.41 ft Percent Full 25.5 % Critical Slope 0.00342 ft/ft Velocity 6.09 ft/s Velocity Head 0.58 ft • Specific Energy 0.83 ft Froude Number 2.53 Maximum Discharge 7.27 fr/s Discharge Full 6.76 ft'/s Slope Full 0.00043 ft/ft Flow Type SuperCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % Normal Depth Over Rise 25.46 % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 6/2312011 4:18:61 PM 27 Siemons Company Drive Suite 200 W Watertown,CT 06795 USA +1.203-768-1666 Page 1 of 2 Page 5 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Circular Pipe - 12 inch HDPE POB4 GVF Output Data Normal Depth 0.25 ft Critical Depth 0.41 ft Channel Slope 0.02130 fUfl Critical Slope 0.00342 ft/fl • • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 6/23/20'11 4:18:61 PM 27 Siemons Company Drive Suite 200 W Watertown,CT 06795 USA +1-203-766-1666 Page 2 of 2 Page 6 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Circular Pipe - 18 inch HDPE POB2 and POB4 Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.010 Channel Slope 0.00880 fUft Diameter 1.50 ft Discharge 7.11 ft/s Results Normal Depth 0.80 ft Flow Area 0.96 ft2 Wetted Perimeter 2.45 ft Top Wdth 1.50 ft Critical Depth 1.03 ft Percent Full 53.2 % Critical Slope 0.00404 ft/ft Velocity 7.44 ft/s Velocity Head 0.86 ft • Specific Energy 1.66 ft Froude Number 1.64 Maximum Discharge 13.78 ft/s Discharge Full 12.81 ft/s Slope Full 0.00271 ft/ft Flow Type SuperCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % Normal Depth Over Rise 53.22 % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s • Bentley Systems,Inc. Wonted Methods Solution Center Bentley FlowMaster [06.07.066.00] 6/23/2011 4:20:28 PM 27 Siemons Company Drive Suite 200 W Watertown,CT 06796 USA +1-209-765-1666 Page 1 of 2 Page 7 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Circular Pipe - 18 inch HDPE P082 and P084 GVF Output Data Normal Depth 0.80 ft Critical Depth 1.03 ft Channel Slope 0.00880 fUfl Critical Slope 0.00404 ft/ft • • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 5/23/2011 4:20:28 PM 27 Slemons Company Drive Suite 200 W Watertown,CT 06795 USA +t-203-766-1666 Page 2 of 2 Page 8 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Circular Pipe - 12 inch HDPE P084 Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.010 Channel Slope 0.02130 ft/ft Diameter 1.00 ft Discharge 0.96 ft'/s Results Normal Depth 0.25 ft Flow Area 0.16 ft2 Wetted Perimeter 1.06 ft Top Width 0.87 ft Critical Depth 0.41 ft Percent Full 25.5 % Critical Slope 0.00342 ft/ft Velocity 6.09 ft/s Velocity Head 0.58 ft • Specific Energy 0.83 ft Froude Number 2.53 Maximum Discharge 7.27 ft/s Discharge Full 6.76 f /s Slope Full 0.00043 fUft Flow Type SuperCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % Normal Depth Over Rise 25.46 % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.086.00] 5/23/2011 4:18:51 PM 27 Slemons Company Drive Suite 200 W Watertown,CT 06795 USA +1-203-755.1886 Page 1 of 2 Page 9 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • Circular Pipe - 12 inch HDPE POB4 GVF Output Data Normal Depth 0.25 ft Critical Depth 0.41 ft Channel Slope 0.02130 ft/ft Critical Slope 0.00342 ft/ft • • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMester [08.01.066.00] 6/23/2011 4:18:51 PM 27 Siemons Company Drive Suite 200 W Watertown,CT 06796 USA +1.203-755.1666 Page 2 of 2 Page 10 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C • 18 inch RCP- Access Road Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.012 Channel Slope 0.01200 ft/ft Diameter 1.50 ft Discharge 5.49 fiats Results Normal Depth 0.70 ft Flow Area 0.80 ft2 Wetted Perimeter 2.25 ft Top Wdth 1.50 ft Critical Depth 0.90 ft Percent Full 46.4 % Critical Slope 0.00510 ft/ft Velocity 6.83 ft/s Velocity Head 0.73 ft • Specific Energy 1.42 ft Froude Number 1.64 Maximum Discharge 13.41 re/9 Discharge Full 12.47 ft2/s Slope Full 0.00233 ft/ft Flow Type SuperCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % Normal Depth Over Rise 46.44 % Downstream Velocity Infinity fUs Upstream Velocity Infinity ft/s • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 6/2412011 2:28:06 PM 27 Slemona Company Drive Suite 200 W Watertown,CT 06796 USA +1-203.756-1666 Page 1 of 2 Page 11 of 12 La Salle Gas Plant Draingae Report FlowMaster Results Appendix C 18 inch RCP- Access Road GVF Output Data Normal Depth 0.70 ft Critical Depth 0.90 ft Channel Slope 0.01200 ft/ft Critical Slope 0.00510 ft/ft • • Bentley Systems,Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 5/24/2011 2:28:06 PM 27 Slemona Company Drive Suite 200 W Watertown,CT 06795 USA -20J-766-1666 Page 2 of 2 Page 12 of 12 • NARRATIVE 1. Explain, in detail, the proposed use of the property. The purpose of the La Salle gas plant is to expand DCP's gathering system to allow DCP to service producers in the Niobrara Shale development to the north and west of DCP's existing facilities. The site for the plant consists of 160 acres. Only 40 acres of the site would be disturbed in the building or operation of the gas plant. The plant will be intended for natural gas processing and will include a high-pressure gathering system. The plant will be fully electric, and a substation will be located at the northeast corner of the plant. (It is possible that location of the substation and parking area, which are currently proposed to be located on opposite sides of the entry road to the plant, will be reversed.) • • • File contains CD with digital copy of Application materials • Please See Original File • Hello