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HomeMy WebLinkAbout03387 - Technical Information Report - Drainage n � ;,.< �M !di'l l N.E.29th Fro_._ ` �' "! �r� (� C��� 6ellewe,Washington 980CIi �.� �,- � '�� ._ � 'S rT`. .u�' F7,- Z�5 R4=- STORM DR.AINAGE ANALYSIS FOR HILLCREST S UARE I� Q RENTON, WASHINGTON r;' , o w �o ' ��, � ti � o,� \ " � � ��� I�NAL � , �ic�s 12/14✓o � �, Prepared by: James A. Morin, P.E. Project Nlanager: David E. Cayton, P.E. Core Project No.: 03127 Date: August 2004 '�3387 ' �,� _ , - . , � su���� ,�rr�� HILLCREST SQUARE TABLE OF CONTENTS I. Project Overview II. Off-Site Analysis ' III. Flow Control/Water Quality Facility Analysis and Design A. Hydraulic Analysis B. Existing Conditions C. Developed Conditions D. Detention Routing Calculations E. Water Quality Volume I IV. Conveyance System Analysis and Design V. Erosion Control Calculations � 1 I. PROJECT OVERVIEW The Hillcrest Square property is located in Section 15, Township 23 North, Rang 5 East W.M. near the intersection of 138`h AVE, SE and SE 128th ST in Renton, Washington (See Figure 1-Vicinity Map). The site is approximately 4.5 acres. The project proposes a mixed-use development to construct 35 town home units and 4 commercial buildings with the supporting roads, curb, gutter, sidewalk and utilities. See Figure 2- Site Plan, far the overall site plan. The existing site is forested. See Figure 3- Land cover for a scaled aerial map of the property. The City of Renton requires Leve12 flow control and the Basic Water Quality menu for the site as specified in the 1998 King County Surface Water Desi�n Manual. The on-site generated runoff will be conveyed to two combined detention/water quality vaults. The two vaults will have their own flow control riser within each vault but the vault outfalls will combine at one common point before leaving the site. Each vault will also have an identical control structure and design water depths so they can be model as one vault. All drainage discharge from the site«�ill be conveyed via pipe to '_�faple«-ood Creek as sho�vn in the plan. ao5 5 4 3 2 ������, � ��,A��� � � C/TY OF RENTON _��`� CONIROL POINT N0. 1848 8 9 10 I I • � � � '�' p � C/TY OF RENTON CONTROL PD/NT M0. 150.� r� �r�.sT. � 5�' "' ��3 � o GREENWooD q '"' cEMETERY QJ�T� 1� 0 N z � 1'1 �y 16 I� � 14 � m � o �� y,�� � � N M � MAP�EWOOD �' CsOLF GOl1R3E w � N .� M o Y l�l/ tl l/ / I Y//�l/ �-1c � � 1" = 3000'f " �.�"���� � SEC. 15, TWP. 23N, f,'GE 5E., W.M. _ ,__ 1�8'8Li 00 B£.00N . ..� _ _ __ __ . _ __— .__ _.���__ -- - -- - _ _ . _. . .,_ �..._. ,. _ -- - �- _ _, _ �- _--._.._1 —.._— --_ _.__�-___-'.--- ------ - ---_______ •---- _� -- _ - - -_.. ._._. 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OFF-SITE AVAL�'SIS Upstream Tributary area This site is located at the top of a drainage basin; the only flow that enters any of the proposed improvements is the surface runoff from the proposed frontage improvements. This offsite drainage remains in the street conveyance system as is not detained. See below for a detailed narrative of the downstream system. I Downstream Anal sis II', Y See Figure 6-Downstream Hydrology, as an aid in the following discussion. ' The storm water runoff that leaves this site, and does not infiltrate, moves to the I east side of the property along 138th Ave SE where the flow enters a conveyance system by way of a catch basin where it is conveyed through the Van Gard property to the east in an 18-inch pipe. The storm water then flows to a release point in the wetland area near the outfall from the Van Gard detention pond where it flows to an unnamed stream that continues south and through the Puget Colony Homes plat. Copies of drainage complaints for this location are included in the appendix of this report. The stream channel continues south for another mile until it combines with water from Maplewood creek From this location the streain��alley opens even more. Isolated pools of sediment deposition and steeper areas of erosion exist along the channel here. This continues unti10.8 miles from the discharge point where the stream enters a pond at the I�'orth-East edge of��aplewood Golf course. ------ --- — -- ----- �'� , CORE. 2- 1 III. FLO�'�' CONTROL/W�TER QUALITY FACILITY ANALYSIS /DESIGN �, i A. HYDRAULIC ANALYSIS The drainage analysis was modeled using the King County Runoff Time Series (KCRTS) software version 4.40g. The site soils are Alderwood(AgC), KCRTS group, Till. The site is located in Sea-Tac rainfall region with a sale factor of 1.0. See the Appendix for the soils map and scale factor exhibit. B. EXISTING CO'�rDITIONS The Bales property is 4.5 acres. The exiting site is all forested for computational purposes. This information was used to produce the Predeveloped Runoff Timeseries (PREDEV) in the KCRTS program. PREDEVELOPED CONDITIONS Total area=4.5 ac Ground Cover Area (ac) Till-forest 4.5 Impervious Area(measured) 0.0 See the KCRTS calculations in the Appendix for the detail Flow Frequency Analysis Time Series File:predev.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- -----Flow Frequency Analysis------- Flow Rate Rank Time of Peak - -Peaks - - Rank Return Prob (CFS) (CFS) Period 0.284 2 2/09/0118:00 0.363 1 100.00 0.990 0.077 7 1/06/02 3:00 0.284 2 25.00 0.960 0.210 4 2/28/03 3:00 0.218 3 10.00 0.900 0.007 8 3/24/04 20:00 0.210 4 5.00 0.800 0.125 6 1/05/05 8:00 0.184 5 3.00 0.667 Q.218 3 1/18/06 21:00 0.125 6 2.00 0.500 0.184 5 11/24/06 4:00 0.077 7 1.30 0.231 0.363 1 1/09/08 9:00 0.007 8 1.10 0.091 Cornptit�ed Peaks 0.336 50.00 0.980 – — `�-- CORE, ,.�-- - 3- 1 C. DEVELOPED CONDITIONS The developed site will consist of 73% impervious area; the remaining area will be till-lawn. The site was measured to determine all impervious area. A tabulation of the areas is included at the end of this section. The modeled detention vault will be split into two vaults with one common control structure/water depths and one common release point just north of the northern most driveway alongl38th AVE SE. Since it is not possible to convey all the storm water run off from Duval Ave NE to the detention water quality vaults, the vaults will be sized to over detain to makeup for the volume. Duval Ave NE will have its own water quality vault. This information was used to produce the Developed Runoff Timeseries (DE� in the KCRTS program. DEVELOPED CONDITIONS Total area=4.5 ac Ground Cover Area (ac) Till-lawn 1.� i.� Imper��ious Area(measured) 3.3 3 �� , `1 )� See the KCRTS calculations in the Appendix far the detail Flow Frequency Analysis Time Series File:dev.tsf ' Project Location:Sea-Tac ��, ---Annual Peak Flow Rates--- Flo« Frequency Analysis------- II ----- � ' Flow Rate Rank Time of Peak - -Peaks - - Rank Return Prob ��, (CFS) (CFS) Period � 0.898 6 2/09/O1 2:00 1.79 1 100.00 0.990 0.755 8 1/OS/0216:00 1.23 2 25.00 0.960 1.07 3 2/27/03 7:00 1.07 3 10.00 0.900 0.843 7 8/26/04 2:00 1.01 4 5.00 0.800 1.01 4 10/28/0416:00 0.956 5 3.00 0.667 0.956 5 1/18/0616:40 0.898 6 2.00 0.500 1.23 2 10/26/06 0:00 0.843 7 1.30 0.231 1.79 1 1/09/OS 6:00 0.755 8 1.10 0.091 Computed Peaks 1.60 50.00 0.980 Hillcrest Square Impervious Area Measurements Location Bldgs Sidewalk Pavement Mixed Use 30,200 sf 5,340 sf 28,200 sf Commercial 26,900 sf 1,730 sf 41 ,230 sf Duvall Ave 0 sf 2,740 sf 6,745 sf ' � N E 4th ST 0 sf 1,150 sf 300 sf 57,100 sf 10,960 sf 76,475 sf Total Impervious: 144,535 sf Total Area %� Mixed Use & ` Commercial 184,290 sf ' '- >�, ��� = �'>>� � � - � � � ��r , - , !, , Duvall Ave 11,723 sf -- � NE 4th ST 1 ,450 sf ' �' ' Total: 197,463 sf Percent Imperviou; 144,535/197,463 = 73% Impervious SEC. 15, TWP. 23N, RGESE., W.M. .. .r� ,,�� � � �� � , r�a` � � , f ,� _ �, � ,����. ., N �� ,�: .,s,. 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" DE I N , a �� , � � - ..;. � - ` � S G � � , ENGINEERING • PLANNING • SURVEYlNG '� - _ .-:i - '� `} .t;.: , + . `-` i �! - �` ' 2 _. '�i!'r �. � �� # - I' � - ��`�'�� � Sl TE L A N O C O �/ER . . .�i''s � _ '' 4 �� ��t�� �, Y� k�.� :��� � F #'�` �� �,� H/L L C R ES T S Q U A R E � �r � � � � �' �� f ` ` > �� ' 1r5 � � � �' �,V a'= " ��� k = � �' � : � _ , � ���'.`�� �` =�� —.3 � .: _ ;:� .'� : ; DATE AUG 2004 SHEET OF , � z � - ,:, . � ,� •�. . � ` � ��-��,a�,� , � _ . �" , F .��__ � . :- .j� ,' . F t;, .. ��� � �.+�` DESIGNED JAM 1 1 , - � . DRAWN JAM PROJECT NUMBER ; 03127 � .., �.��.,J3\03��,���,�r\Ex,�,,,,���„3127����.��rial.dwy,O/G7�ZOLY O.J7.Z3 AI°I n��� � �° �� �? ��;� ����•tin.. ' . . . ,. j� �. �� �� , ,,���� ��.,. 3 , �., ..;�� .. Ls ;. , ,��''"JI„ B ��, t i, � �� � . � �' ;, ��� ,� � „ �, �,��,.,������� ,��� � � ; � _ �..:':�g���;�I�J��a+.�iYr Mn;�ra�w�i�yp rkddhe��. `�, .. 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DETENTION ROlTT1NG CALCi-LATIONS The City of Renton requires that the Level 2 Flow Control standard apply to this project. This standard requires that the proposed pond outfall match '/2 the predeveloped release rate and not exceed the other predeveloped design storm events up to the 50 year event. The pond is also required not to exceed frequency and duration for these storm events. Using the appropriate release rates the developed timeseries was modeled in a vault with 7.1-feet of water depth and a pond bottom of 10,640 sf(304' x 35'). A two-orifice control structure was design to meet the release rates and frequency duration standards. See the Appendix of this report for the detailed KCRTS calculations. The resultant vault volume required was 64,900 cf. The volume provided on the plan is 66,661 cf. Therefore the vaults, as shown on the plans are adequate to provide the required volume and maintain the frequency and duration of storm runoff from the project. ^ t , ��. Live Storage �`� ;��� 64,900 cf required Site constraints do not allow for all the storm water detention and water quality to be contained within one vault. Therefore t��vo vaults are proposed. Both vaults will , have the same release characteristics (head,water depth and orifice sizes), which will be like the detention vault modeled in the KCRTS program. The outfall pipe for the two vaults will connect together at one common manhole before conveying offsite. Volume Summary: South Vault=20'x 185' x 6.23' =23,051 cf North Vault=35' x 200' x 6.23' =43,610 cf Total volume provided=23,051 +43,610 = 66,661 cf Total volume required =64,900 E. VVATER QUALITY VOLUAIE The water quality volume for Hillcrest Square was calculated using the King County Surface Water Design Manual (KCSWDM), 1998 Edition, pages 6-68 to 6-71. Vb= f*(0.9A; + 0.25A,g+ O.lOAtr+ O.lOAa)*(R/12) Where, Vb=wetpool volume (c� f=volume factor A; = area of impervious surface (s� Atg=area of till soil covered with grass (s� Atf= area of till soil covered with forest (s� Ao= area of outwash soil covered with grass or forest R=rainfall from mean annual storm (inches) (refer to the attached precipitation graph) Onsite Vr=0.90*Ai + 0.25*Ag X R/12 Vr= [0.90*(3.3*43560) +0.25*(1.1*43560)] x R/12 Vr= (129,373 � 11,979) x 0.47 i 12 Vr= 5,537 Vb =3xVr Vb = 3 * 5,537 Vb = 16,610 cf Dead Storage 16,610 cf required Onsite Duvall Ave NE Vr=0.90*Ai + 0.2�*Ag X R/12 Vr= [0.90*(6745) ] x R/12 Vr=(6745) x 0.47/ 12 Vr= 264 Vb = 3 x Vr Vb =3 * 264 Vb = 792 cf Dead Storage 792 cf required Duvall Ave NE � IV. Conveyance System Anatysis and Design The Conveyance System design follows the City of Renton standard, which is based upon the 1998 King County Surface Water Design manual.This standard requires the conveyance pipe to be sized to convey the 25-year design event. The developed site timeseries modeled for this project produces a 25-year design flow of 2.61 cfs.A 12-inch pipe has a maximum capacity of 3.5 cfs with inlet control and independent of pipe slope. Therefore the 12-inch pipe shown on the plans is adequate. Complete pipe siaing calculations ���ill be provided at final submittal. V. Erosion Control Calculations The Erosion control design follows the City of Renton standard, which is based upon the 1998 King County Surface Water Design manual.This standard requires a site that is o�-er 3 acres in size to utilize a sedimentation pond(instead of a sedimentation trap). Sedimentation Pond Surface area: SA=Fs(QZNs) Q� = 1.01 CFS (see drainage calcs,developed timeseries,dev) Vs=0.00096 (given KCSWDM) Fs =2 (Factor of safety, KCSWDM) SA=2*(1.01 / 0.00096) SA=2105 SF—required SA=2500 SF —provided (25 x 100) Dewatering Orifice Design: Ao=As(2h)°�'/0.6*3600*Tg°5 As =2105 (see calculation above) h=3.5' (Riser height used) T =24 hours (given) g= 32.2 ft/secz (given) Ao = 2105(2)(3.5) 0�5/ 0.6*3600*(24)(32.2)o.s Ao =0.0189 D = 13.�4*(Ao) °�' =13.54*(0.0189) o.s D = 1.86", say 1-7/8" TerraServer Image Courtesy of the USGS Page 1 of 1 S���:I i o Pi It Flru t>-,:(C 1 u 1 ci��t5�:i v.� (�i�any��ii, I t�:-I,' I`�u��i',�Ze 51�u1:�tir�n I iitzs i�I �ii��c�; P�i I af��li;a��e :iJS� �t��itt�r�, �Nla�teir��ton, l���it��f �t���s l)1 .1ui 199� ..� � ^::;� ''��,' -��- � _ �. ,A � `. .• ;` $r , - . f . � . .. � �->"�, � i � , ir , �I� . a.�. , ,,` •i M+ � � T ! I { - :�, 1 � } �' 1 • � �"'' e i i ! 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'� ioC 1 ` �.AkF � a`� �-� r ,�4 ♦ �`�N � C �`rU AkF ., Park Ng r PY � � \��, '� � n - - p Cp�`` .e.'•I � '��—..� I �r� 1� ' � AGUE �_ _--� �\�\1, `,`` �,� 1`0`�o EvC n.gC `'� ' � ..�/ ii I -_.��agp AkF M � B` ��� j -- -- -- � 2 � — `''-. �S ---_- -- a- -- --- ----a ---�---- L � `-�;- --- -�-------�---�-- ��_ ':_ '--- BM�"--o�BM 27'30ir � - -- �A B � '-------o_--�_-�-__4��`--- _ � pgC°----- '--- � ° -- _ _ ._ I qgp AgC AgD �- AkF 8 BMp � ' `�`� � f � 428 I�c� �� � /^"✓ o n.. \. `` I PIP:2UNF AmC i A�;� ; , �..` _� � -- --- �:'��,. ; ��� � ' j KING COUNTY SO�LS MAP .. s �.� , � � ;�:-F,�\ . , �, No ��� �, �°�� ��-� I '�'i•` . c i �E. - � ._ .. r1��, --� 3.2.2 KCRTS/RUNOFF FILES METHOD—GENERATING TIME SERIES TABLE 3.2�.B EQUIVALENCE BETWEEN SCS SOIL TYPES AND KCRTS SOIL TYPES SCS Soil Type SCS KCRTS Soil Notes Hydrologic Group Soil Group � Alderwood (Ag6,AgC,AgD) C � _ Till Arents, Alderwood Material (AmB, AmC) C Till Arents, Everett Material (An) B Outwash 1 Beausite (BeC, BeD, BeF) == C Till 2 Bellingham (Bh) D Till 3 Briscot (Br) D Till 3 Buckley (Bu) D 7ill 4 Earlm�nt (Ea) D Till 3 Edgewick (Ed) C Till 3 Everett(Ev6, EvC, EvD, EwC) A/B Outwash 1 Indianola (InC, InA, InD) A Outwash 1 Kitsap (KpB, KpC, KpD) C Till Klaus(KsC) C Outwash 1 Neilton (NeC) A Outwash 1 Newberg (Ng) B Till 3 Nooksack (Nk) C Till 3 Norma (No) D Till 3 Orcas (Or) D Wetland Oridia (Os) D Till 3 Ovall (OvC, OvD, OvF) C Till 2 Pilchuck (Pc) C Till 3 � Puget(Pu} D Till 3 Puyallup (Py) B Till 3 Ragnar(RaC, RaD, RaC, RaE) B Outwash 1 Renton (Re) D Till 3 Salal (Sa) C Till 3 Sammamish (Sh) D Till 3 Seattle (Sk) D Wetland Shalcar(Sm) D Till 3 Si (Sn) C Till 3 Snohomish (So, Sr) D Till 3 Sultan (Su) C Till 3 Tukwila (Tu) D Till 3 Woadinville (Wo) D Till 3 Notes: 1. Where outwash soils are saturated or underlain at shallow depth (<5 feet) by glacial till,they should be treated as till soils. 2. These are bedrock soifs, but calibratian of HSPF by King County DNR shows bedrock soils to have similar hydrologic response to till soils. 3. These are allu�ial soils,some of which are underlain by glacial till or have a seasonally high water table. In the absence of detailed study,these soifs should be treated as till soils. . 4. Buckley soils are formed on the low-permeability Osceola mudflow. Hydrologic response is assumed to be similar to that of till soils. F998 Surface Water Desi?n D-ianual 9/1/98 3-?5 SECTION 3.2 RUNOFF COMPUTATION AND AN.4LYSIS MEIT30DS FIGURE 3.2.2.A RAINFALL REGIONS AND REGIONAL SCALE FACTORS ST 1.0! . ST 1.0 LA 0.8 LA 0.9 � 1-0 LA 1.2 ST 1.1 - =�o�o,.,=��o��T. � u . 7l'.� �♦ ���f 1 ' .�M�� M AINO COUMiY . _� ��..,��T'i _ �p', \ ` ^ .:; y _�,\ s , 5-„ .r—�_i�� i�J � , ,�� � � _� ' �..�7i� �`::� �¢; na _ '.5 T�- i_ �_� Q r� � . � i •y� i• ; I •' _�'1� �Eo�n�o I,� r` J �4,'�—/. \I IOMRIAM1� 1 J i I� i�T � ;. I �•'Y'IiE ON��^^"( �% I ,�—+ I T � „ �� _/ _J C`'�:, l _ y_��' . { LL_! �i ' `� � I-' �, �' ;;- Fv" ' 8 J � , ` ! t`` , , s;' �:• � � _ ` ^� , a�w , �..� i { � !y=%p� - �. "; 3 ¢�� _ � �-- � �I � , \ ; �A � �_. 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Regional Scale Factors �A o.s �—�,� � ;:�� Incorporated Area LA 1.0 LA 1.2 ...c� RivedLake Major Road K.CrR.T.S., REGIONAL SCALE FACTOR 9/1/98 1998 Surface R�ater Design Manual 3-22 , � � , Release Rates Flow Frequency Analysis Time Series File: rp edev.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- -----Flow Frequency Analysis------- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob (CFS) (CFS) Period 0.284 2 2/09/O1 18:00 0.363 1 100.00 0.990 ' 0.077 7 1/06/02 3:00 0.284 2 25.00 0. 960 0.210 4 2/28/03 3 :00 0.218 3 10.00 0.900 0.007 8 3/24/04 20:00 0.210 4 5. 00 0.800 0.125 6 1/05/05 8:00 0.184 5 3.00 0.667 0.218 3 1/18/06 21:00 0.125 6 2.00 0.500 0.184 5 11/24/06 4:00 0.077 7 1.30 0.231 0.363 1 1/09/OS 9:00 0.007 8 1.10 0.091 Computed Peaks 0.336 50.00 0.980 ' Time Series File:dev.tsf ' Project Location:Sea-Tac ' ---Annual Peak Flow Rates--- -----Flow Frequency Analysis------- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob (CFS) (CFS} Period 0.898 6 2/09/O1 2:00 1.79 1 100.00 0.990 0.755 8 1/05/02 16:00 1.23 2 25.00 0.960 1.07 3 2/27/03 7:00 1. 07 3 10.00 0.900 0.843 7 8/26/04 2:00 1.01 4 5.00 0.800 , 1.01 4 10/28/04 16:00 0.956 5 3 .00 0.667 ! 0.956 5 1/18/06 16:00 0. 898 6 2 .00 0.500 � 1.23 2 10/26/06 0:00 0.843 7 1.30 0.231 ' � 1.79 1 1/09/08 6:00 0.755 8 1.10 0.091 '' Computed Peaks 1 .60 50 .00 0.980 �I Time Series File:rdout.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- -----Flow Frequency Analysis----- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob (CFS) (CFS) (ft) Period 0.261 2 2/09/O1 20:00 0.349 6.12 1 100.00 0.990 i 0.062 7 1/07/02 3 :00 0.261 5.71 2 25.00 0.960 0.221 3 3/06/03 22:00 0.221 5.10 3 10.00 0.900 0.053 8 8/26/04 6:00 0.211 4 .96 4 5.00 0.800 0.063 6 1/08/05 4:00 0.102 4.12 5 3 .00 0.667 0.102 5 1/19/06 1:00 0.063 3.44 6 2 .00 0.50C 0.211 4 11/24/06 8:00 0.062 3 .28 7 1.30 0.231 0.349 1 1/09/OS 12 :00 0.053 2 .37 8 1.10 0.091 Computed Peaks 0.320 6. 11 50 .00 0.960 Retention/Detention Facility Type of Facility: Detention Vault Facility Length: 304.00 ft Facility Width: 35.00 ft Facility Area: 10640. sq. ft Effective Storage Depth: 7.10 ft Stage 0 Elevation: 395.65 ft Storage Volume: 75544. cu. ft Riser Head: 6.10 ft Riser Diameter: 12.00 inches Number of orifices: 2 Full Head Pipe Orifice # Height Diameter Discharge Diameter (f t) (in) (CFS) (in) 1 0.00 1.13 0. 085 2 4.00 2 .25 0.208 6.0 Top Notch Weir: None Outflow Rating Curve: None Stage Elevation Storage Discharge Percolation (ft) (ft) (cu. ft) (ac-ft) (cfs) (cfs) 0.00 395.65 10640. 0.244 0.000 0.00 0.01 395.66 10746. 0.247 0.004 0.00 0 .02 395.67 10853. 0.249 0.005 0.00 0 . 04 395.69 11066. 0.254 0.006 0.00 , 0. 05 395.70 11172. 0.256 0.007 0.00 0 . 06 395.71 11278. 0.259 0.008 0.00 0 . 07 395.72 11385. 0.261 0.009 0.00 0 . 08 395.73 11491. 0.264 0.010 0.00 I 0 . 09 395 .74 11598. 0.266 0.011 0.00 0 .20 395.85 12768. 0.293 0.015 0.00 0 .30 395.95 13832. 0.318 0.019 0.00 0 .40 396.05 14896. 0.342 0.022 0.00 0.51 396.16 16066. 0.369 0.024 0.00 0.61 396.26 17130. 0.393 0.027 0.00 , 0 .71 396.36 18194. 0.418 0.029 0.00 0 .82 3.96:47 19365. 0.445 0.031 0.00 0 . 92 396.57 20429. 0.469 0.033 0.00 ' 1. 02 396.67 21493. 0.493 0.035 0 .00 1. 13 396.78 22663 . 0.520 0.036 0.00 1 .23 396.88 23727. 0.545 0.038 0.00 1 .33 396.98 24791. 0.569 0.040 0.00 1 .44 397.09 25962. 0.596 0.041 0.00 1 .54 397.19 27026. 0.620 0 .043 0.00 1.64 397.29 28090. 0.645 0.044 0.00 1.75 397.40 29260. 0.672 0.045 0.00 1. 85 397.50 30324. 0.696 0.047 0.00 , 1 . 95 397.60 31388. 0.721 0.048 0.00 2 . 06 397.71 32558. 0.747 0.049 0.00 2 . 16 397.81 33622 . 0.772 0.050 0.00 2 .26 397.91 34686. 0.796 0.052 0.00 � 2 _37 398 .02 35857 . 0. 823 0 .053 0. 00 ' 2 .47 398 .�_2 36921 . �`. 8-�8 0 . 054 0 . 00 2 .58 398.23 38091. 0.874 0.055 0.00 I 2 .68 398.33 39155. 0.899 0 .056 0.00 2 .78 398.43 40219. 0.923 0.057 0.00 I 2 . 89 398.54 41390. 0.950 0.058 0.00 2 . 99 398.64 42454. 0.975 0.059 0.00 3 .09 398.74 43518. 0.999 0.060 0.00 3 .20 398.85 44668. 1.026 0.061 0.00 3 .30 398.95 45752. 1.050 0.062 0.00 3 .4a 399.05 46816. 1.075 0.063 0.00 3 .51 399.16 47986. 1.102 0.064 0.00 3 .61 399.26 49050. 1.126 0.065 0.00 3 . 71 399.36 50114. 1.150 0.066 0.00 3 .82 399.47 51285. 1.177 0.067 0.00 3 .92 399.57 52349. 1.202 0.068 0.00 4 .00 399.65 53200. 1.221 0.069 0.00 ' 4 .02 399.67 53413. 1.226 0.070 0.00 � 4 .05 399.70 53732. 1.234 0.074 0.00 � 4.07 399.72 53945. 1.238 0.081 0.00 4 .09 399.74 54158. 1.243 0.090 0.00 4.12 399.77 54477. 1.251 0.102 0.00 4.14 399.79 54690. 1.256 0.115 0.00 4.16 399.81 54902. 1.260 0.126 0.00 4.19 399.84 55222. 1.268 0.130 0.00 4.29 399.94 56286. 1.292 0.145 0.00 4 .39 400.04 57350. 1.317 0.158 0.00 I� 4.50 400.15 58520. 1.343 0.170 0.00 � 4 .60 400.25 59584. 1.368 0.180 0.00 j 4.70 400.35 60646. 1.392 0.190 0.00 4.81 400.46 61818. 1.419 0.199 0.00 4.91 400.56 62882. 1.444 0.207 0.00 5.01 400.66 63946. 1.468 0.215 0.00 5.12 400.77 65117. 1.495 0.223 0.00 5.22 400.87 66181. 1.519 0.230 0.00 5.32 400.97 67245. 1.544 0.237 0.00 5.43 401.08 68415. 1.571 0.244 0 .00 5.53 401.18 69479. 1.595 0.251 0.00 5.63 401.28 70543. 1.619 0.257 0 .0� 5.74 401.39 71714. 1.646 0.263 0 .00 5.84 401.49 72778. 1.671 0.269 0.00 5.95 401.60 73948. 1.698 0.275 O.00 6.05 401:70 75012. 1.722 0.281 0.00 6.10 401.75 75544. 1.734 0.284 0.00 6.20 401.85 76608. 1.759 0.597 0.00 6.30 401.95 77672. 1.783 1. 170 0.00 6.40 402 .05 78736. 1.808 1. 900 0.00 6_50 402.15 79800. 1.832 2.700 0.00 6.60 402.25 80864 . 1.856 2.980 0. 00 6.70 402.35 81928. 1.881 3 .240 0. 00 6 . 80 402.45 82992 . 1.905 3 .480 0. 00 6. 90 402.55 84056. 1. 930 3 .710 O. 00 7. 00 402.65 85120. 1. 954 3 .920 0. 00 7. 10 402.75 86184 . 1. 979 4 .120 0. 00 7.20 402 .85 87248. 2. 003 4 .300 0.00 7 .30 402.95 88312 . 2.027 4 .490 0.00 7.40 403 .05 89376. 2.052 4 .660 0.00 7 .50 403 .15 90440 . 2 . 076 4 .830 O. OQ 7 . 60 403 .25 91504 . 2 . 101 4 . 990 0 . 00 7 .70 403 . 35 92568. 2 . 125 5 . 140 0 .00 7 . 80 403 .45 93632. 2 . 149 5 .290 0.00 7 . 90 403 .55 94696. 2 .174 5.440 0.00 8 . 00 403.65 95760. 2.198 5.580 0.00 8 . 10 403.75 96624. 2.223 5.720 0.00 Hyd Inflow Outflow Peak Storage Target Calc Stage Elev (Cu-Ft) (Ac-Ft) 1 1.81 ******* 0.28 6.07 401.72 75210. 1.727 2 0.91 0.33 0.26 5 .71 401.36 71381. 1.639 3 1.09 0.21 0.22 5.10 400.75 64873. 1.489 4 1.23 ******* 0.21 4 .96 400.61 63420. 1.456 5 0.97 ******* 0.10 4 .12 399.77 54465. 1.250 6 1.01 0.06 0.06 3.44 399.09 47291. 1.086 7 0.76 ******* 0.06 3.28 398 .93 45577. 1.046 8 0.84 ******* 0.05 2.37 398 .02 35870 . 0.823 Duration Comparison Anaylsis Base File: predev.tsf New File: rdout.tsf Cutoff Units: Discharge in CFS -----Fraction of Time----- ---------Check of Tolerance------- Cutoff Base New �Change Probability Base New %Change 0.064 � 0.90E-02 O.10E-01 10.8 I 0.90E-02 0.064 0.065 1.6 0.081 � 0.62E-02 0.30E-02 -51.7 I 0.62E-02 0.081 0.067 -16.9 0.098 � 0.47E-02 0.27E-02 -44 .0 I 0.47E-02 0.098 0.068 -30. 1 0.115 � 0.36E-02 0.24E-02 -34 .1 I 0.36E-02 0.115 0. 070 -38. 9 0.131 � 0.28E-02 0.20E-02 -28.3 I 0.28E-02 0.131 0.091 -31.0 0.148 � 0.22E-02 0.17E-02 -22.4 � 0.22E-02 0.148 0. 127 -14.5 0.165 I 0.15E-02 0 .15E-02 0.0 � 0.15E-02 0.165 0.165 0.0 0.182 I 0.96E-03 0 .11E-02 16. 9 I 0.96E-03 0.182 0.193 6.1 0.199 I 0.60E-03 0.86E-03 43 .2 I 0.60E-03 0.199 0.210 5.1 0.216 I 0.34E-03 0.44E-03 28.6 I 0.34E-03 0.216 0.220 1.6 0.233 I 0.21E-03 0.23E-03 7.7 � 0.21E-03 0.233 0.239 2.5 0.250 I 0.16E-03 0.13E-03 -20.0 � 0.16E-03 0.250 0.246 -1.7 0.267 � 0.82E-04 O.00E+00 -100.0 � 0.82E-04 0 .267 0.257 -4.0 Maximum positive excursion = 0.015 cfs ( 8.3%) occuring at 0.184 cfs on the Base Data:predev.tsf and at 0.200 cfs on the New Data:rdout.tsf Maximum negative excursion = 0.049 cfs (-39.3%) occuring at 0.125 cfs on the Base Data:predev.tsf and at 0. 076 cfs on the New Data:rdout.tsf