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Item 4D - St Laurence Flood StudyST. LAURENCE FLOOD STUDY North Jones Branch Southlake, TX n i ln�Uisat Ud t� N tp � ee y� •/ ,E p ry t �p x 4 � r PROJECT SITE C ra 41 hi n � O • �'"'r-� � � is c R,Slaf.tftphwty 174 a E Suutlilasio fStvA w � ;:,�„ •,, c„�. �; Y Prepared by: Foose Engineering & Development Services TBPE Firm No. F-26471 Prepared for: 3 jrkman EN(:I�il EflihG J u ly 9, 2024 Material Copyrighted ©All Rights Reserved E OF r + i y,�P�,.. •�� q * ' �. ..... ••�JOHN•W��FOOSE . ..... 144124 �•��; Kirkman Engineering Attn: Sydney Foster 5200 State H i g hway 121 Colleyville, TX 76034 Re: Flood Study - North Jones Branch Project Name - Saint Laurence Church, Southlake, Texas Dear Ms. Foster: Enclosed herewith is the Flood Study Report for North Jones Branch to support the proposed improvements at Saint Laurence Church in Southlake, Texas. This report includes hydrologic and hydraulic modeling and results for the existing and proposed conditions for existing flows. Should you have any questions or concerns, please do not hesitate to contact me at (214) 986-2283 to discuss any items related to this Report. Sincerely, John W. Foose, P.E., CFM President Foose Engineering & Development Services TBPE Firm Registration No. F-26471 Foose Engineering & Development Services Contents Saint Laurence Church Flood Study North Jones Branch J u ly 9, 2024 1.0 Project Description..............................................................................................................................4 1.1 Purpose.......................................................................................................................................................4 1.2 Site Location and Proposed Improvements........................................................................4 1.3 FEMA Flood Insurance Rate Map...............................................................................................4 1.4 Data Collection.......................................................................................................................................4 2.0 Hydrologic Analysis......................................................................................................................................7 2.1 Existing Conditions...................................................................................................................................7 2.2 Hydrologic Results...................................................................................................................................11 3.0 Hyd ra u I ic Ana lysis ........................................................................................................................................11 3.1 Pre-Project.....................................................................................................................................................11 3.2 Post-Project.................................................................................................................................................12 3.3 Hydraulic Results.....................................................................................................................................12 4.0 Conclusion.......................................................................................................................................................18 List of Tables Table 1 - Existing Conditions Hydrologic Parameters........................................................................8 Table 2 - Existing Conditions 100-yr Hydrologic Results..................................................................11 Table 3 - Proposed Culvert Dimensions.....................................................................................................12 Table 4 - Comparison of100-yr EX Conditions WSELs.....................................................................13 Table 5 - Comparison of100-yr EX Conditions WSELs with Prop. Culvert ...........................13 Table 6 - Comparison of 100-yr EX Conditions Channel Velocities...........................................14 Table 7 - Comparison of100-yr EX Conditions Channel Velocities with Prop. Culvert.15 List of Figures Figure1 - Vicinity Map.............................................................................................................................................5 Figure2 - FEMA FIRM..............................................................................................................................................6 Figure3 - Basin Map................................................................................................................................................9 Figure4 - Hydrologic Workmap.....................................................................................................................10 Figure5 - Hydraulic Workmap........................................................................................................................17 3 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 Foose Engineering Saint Laurence Church Flood Study & Development Services North Jones Branch J u ly 9, 2024 1.0 Project Description 1.1 Purpose The purpose of this flood study is to evaluate the 100-year existing peak discharges for North Jones Branch at Saint Laurence Church and appropriately size a proposed box culvert. The culvert is to be sized so as to create no adverse impacts offsite. To achieve this, a hydrologic and hydraulic evaluation was performed for the watershed and stream. 1.2 Site Location and Proposed Improvements Saint Laurence Church is located in Southlake, TX near the intersection of Kimball Ave and State Highway 114. The North Jones Branch runs through the site, flowing from the southwest corner to the northeast corner of the property. There is an existing church complex on the site currently, with proposed improvements to be made. One of the improvements is a proposed culvert crossing near the northeast edge of the property. The site location can be seen in Figure 1. 1.3 FEMA Flood Insurance Rate Map North Jones Branch is currently mapped within FEMA Special Hazard Area, designated Zone X on the Flood Insurance Rate Map (FIRM) 48439C0105K dated September 25, 2009, as shown in Figure 2. 1.4 Data Collection Data obtained in support of the Saint Laurence Church flood study includes: • Texas Natural Resources Information System (TNRIS) 1-m LiDAR Digital Elevation Model Dated 2019 • On -site topographic survey provided by Kirkman Engineering June 2024 • Soils provided by USDA Natural Resources Conservation Service (NRCS) • Site, Paving, and Grading plan provided by Kirkman Engineering June 2024 The horizontal datum utilized for the project is NAD83 Texas State Plane North Central Zone FIPS 4202. The vertical datum is NAVD88. 4 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 No Text ZONE X CITY OF SOUTHLAKE 480612 CE m MAIN > z STREET w O �� � TRP STREET a NORTHWOOD GARDEN gR�P� S R. COURT SWEET SCENIC DRIVE E X WOODHAVEN DRIVE � w z m w o� > rn O J DR Lu PINEF CHRIS LAN J a w THOMAS COURT 114 LLw LL �[ w _U) 0 m Y \`> ZONE X LILLCASTLE STREET EX > BROOKWOOD LANE / ZONE 9AINFOR� \ cP Io Y a O Foose Engineering & Development Services 2.0 Hydrologic Analysis Saint Laurence Church Flood Study North Jones Branch J u ly 9, 2024 A hydrologic analysis was performed for North Jones Branch to determine existing peak discharges in the stream. This evaluation provides the peak discharges leaving the site to determine the flow to be used in the hydraulic analysis. An existing conditions SCS Unit Hydrograph model was created for the analysis using HEC-HMS version 4.12 The following sections will provide more detail for both the pre -project and post -project analysis. 2.1 Existing Conditions The drainage area for North Jones Branch was delineated using 1-ft contours generated from 2019 TNRIS LiDAR data. The watershed upstream of the project site extends to the south of State Highway 114. The total area of the upstream watershed was calculated to be 495.1 acres. The watershed was divided into 3 subbasins at logical drainage divides. The watershed delineation is shown in Figure 3. The basin is comprised of B, C, and D type soils provided by the NRCS. A soils map is provided in Figure 3. The SCS Curve Number and iSWM time of concentration methods were used to estimate losses and lag times, in accordance with the City of Southlake criteria. The time of concentration was calculated using the longest flowpath using TNRIS 1- foot contours and the equations used for calculating sheet, shallow, and channel flow per City of Southlake standards. The calculations for the longest flow path can be found in Appendix B. The time of concentration for each basin is provided in Table 1. The existing conditions land use was determined using the most recent available aerial imagery of the watershed. The curve number calculations can be found in Appendix B. The curve number for each basin is shown below in Table 2. The land use can be seen in Figure 4. Lag time and Muskingum-Cunge routing was used for the model. The lag time methodology was used for a reach that consisted of pipe network flow. For the open channel reach, Muskingum-Cunge Routing was used. TNRIS 1-foot contours were used to develop an eight -point cross section for the reach. A frequency storm metrological model was utilized using precipitation data from Atlas 14 for the 100-yr storm event. Rainfall data is provided in Appendix B. 7 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 Foose Engineering & Development Services Table 1- Existing Conditions Hydrologic Parameters Saint Laurence Church Flood Study North Jones Branch J u ly 9, 2024 A 1 0.202917 115.2 191.8 B 10.234223 127 91.7 C 10.336450 125 83.5 8 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 Oka � � / 1 q� V 670v .�....� 0 r • - I O � SSO.i 1 i K3 �w V 'flrkman .'/ � � °'o r560 580' FNGfNEERING - �y 1 � a `sso 560 I'"T4 • SAINT LAURENCE CHURCH ,� ;� a►'-�„ SOUTHLAKE, TX NORTH ]ONES BRANCH FLOOD STUDY t _ FIGURE 3: - �� '�a��• {'S90 6` c SOILS MAP � �_ • !`� . �•,� is +`pp r 6, � s♦ 5g0 ro 0 1 A� 620 Project Site ° > � 0 ,� Basins 41 r -• r J i soil agov .4 B .. 620 G20 ! r _ r 610 610 B i f �f ' , F y4 0 / ,�"�: ♦ �0`60 620 /^ - _ , ��9 '• • i 620 620 ' 1. A. . -. _ _ - 640— _ 640 Index Contours 1 , yAo' 1Si�'' y�N.c • I o �°�`�,� •c. - . 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'.: k ;gyp ►a. - �•.W�!!'4y1 a� o ' "' ...��L ..._ r 1i AI,►' .. . ,�i��o o ""774.�64 ,ti q J �. vC � ♦ � t ism a � • �: •-� � &�, i � �y +.0';, TZ 670• �y�` "7 el 62o�i} � ' ' • � -Y r r e � �0 0 , _. � _ � x s' � �� '' � ..: sso _.- � t .yY � ' � ,� "-•�.� a� �, .'�= 1 �, w _ of , � • Y � "_•��= � �, � 02° 1 a 0. y •' I 630 r •'{ _) % • � r 68p':.6�0 �t 0 750 11500 ft 380 AL FOOSE ENGINEERING & t ,��. o• t �0 650� 4� ; I DEVELOPMENT SERVICES U o. `v ,,� 0• ». �t,�i��.lr '�' ' Lo _ t _ - TBPE&LS Engineering Firm No. F-26471 4625 Greenville Ave, Suite 305 a Ai� Dallas, TX 75206 IM M 670 I t,:4 640., 0 0 V3 650� LAI 14 AR ft T Y' 660►co°j C 3� r 630 j NOW A r_ yF1i �3p N � �� , �'' , 1 � i w � � � � �' g - O.Le J►a . •'t � ,","H \\I{ , ,1 My 1 • /(630Q7, a T 62a1 K3 Kirkman FNGIN EIRING SAINT LAURENCE CHURCH SOUTHLAKE, TX NORTH ]ONES BRANCH FLOOD STUDY FIGURE 4: HYDROLOGIC WORKMAP o , , 60u 0 1''��620 co CIE h600���,'. Project Site �o 0 Basins 610 4 ► 0 610 ypo ) sNo �� ` in'II �{. 1 Contours 620 ,y 60° 0 600 610 010� ,� ', 1'1 ' Longest_Flowpath Channel 20 - 610 610 -- -- 610 6 — _ '� / `610 �. t7.::':�� i 610 ,`or 620 - -- 620 20 '. Shallow _ -. -�---- _ 620 t _�^ " 620 630 Sheet 0 600 610 -- � - 630 - •� � i~ _ — =��—_63 Land Cover O 630 6 620 1 Acre Residential µ p ,�1/2 Acre Residential �+7Y IA ; � : g40 , I • 630 °� 2 Acre Residential 630 � 62p _ ... / 620 °�i, _, '� ,Rf'c Y,.i ". 'v. ! a0 ♦''3 _ _ �'. 650 ,�':6so - — N - Commercial 'Ls sS0 �O No ,I,t o 640 660 660 660 �'ss° 1656_,._. Open Space -Good 8 Paved Road - Ditch 00 6jo � Ms6p .. 1, f twpt � r , 1" . � .f : ti s 6ry o o ° `y ,•.vr =,��, `.- °� K Contours Major Contour 30 ,rtiit ,..�r sop Minor Contour 630 60 00 c.(c ti��'. mb, ° o ao g0 hp o fO �,yo m � o 0 610 0 `�• egoego., � �, ,� "' �9, yt �''��/' � t'� � !!l...,+Y�1 ■r►`� ���mo °� 630 630 s �L� ` r68 000_ .i o C� ssO o`Oo s �eL 680 6 4, r �Mo ayo �f`���-��a `� 1,�� ,r�T; •/� j�je6 f ss°��K'� '"—,� �C 680 .i rP1% 6 �, - - ,� ,�:: .�► �;,i�; ttr — 0 750 11500 ft o�o/ �n�J�,o� �♦ , _�� �Ala "' i1�11�.�.i�'�, ��I�:- ��. Gym / �p �� O r � ► �,. ��e�o . I 1 t I sso 680 i 64o FOOSE ENGINEERING & ✓Ati 0 64 6' in " �� 1. DEVELOPMENT SERVICES s j o� J "_' TBPEUS Engineering Firm No. F-26471 } r� 660 r� X' • Jl � p r. ��� s° �� 6,.,_ 1i I 6 4625 Greenville Ave, Suite 305 c .r d�� � ��' �-.L� s�o�=,sso Dallas, TX 75206 Foose Engineering & Development Services 2.2 Hydrologic Results Saint Laurence Church Flood Study North Jones Branch J u ly 9, 2024 The results in peak discharges are shown below in Table 2. The results are showing in hydrological order. A hydraulic analysis was performed for North Jones Branch using the results from the hydrologic analysis. Section 3.0 describes the hydraulic modeling. Table 2 - Existing Conditions 700 yr Hydrologic Results C 1918.5 B 1678.0 Junction -BC 11596.5 Junction -A 11578.9 A* 1548.6 O utfa I I 12113.8 *includes project site 3.0 Hydraulic Analysis A hydraulic model was developed for North Jones Branch to evaluate impacts of the proposed improvements along the stream at the project site. A hydraulic model was created using HEC-RAS version 6.5. The following sections will provide more detail for both the pre -project and post -project analysis. 3.1 Pre -Project Cross -sections were cut from a few hundred feet downstream of the property boundary through the site to the downstream face of the Kimball Ave. culvert. The cross sections were cut using survey contours provided by Kirkman Engineering and 2019 TNRIS LiDAR DEM to develop an existing conditions geometry for the stream. Recent aerial imagery was used to determine the roughness coefficients for the channel and overbanks of the model. The Manning's n-values range from 0.03 in the channel and 0.04 in the overbanks. Guidelines from Ven Te Chow's Open Channel Hydraulics, published in 1959, were used to determine Manning's n-values for the terrain through the reach. 11 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 Foose Engineering Saint Laurence Church Flood Study & Development Services North Jones Branch J u ly 9, 2024 The existing conditions flow from Section 2.2 were used for the hydraulic model. Normal Depth boundary conditions were used for the upstream and downstream boundary conditions. The results are shown in Tables 4 and S. 3.2 Post -Project The pre -project model was used as the starting point for the post -project hydraulic analysis. The post -project analysis was broken into two separate conditions. The first condition incorporated the proposed grading. The second condition incorporated the proposed grading as well as a proposed culvert. In the first post -project condition, the proposed grading contours were added to the model and the cross -sectional geometries were adjusted accordingly. The flows from the hydrologic analysis in Section 2.2 were used. In the second post -project condition a culvert was sized at the northeast corner of the property (see site plan provided in Appendix A for location). The dimensions of the culvert are shown in Table 3 below. Table 3 - Proposed Culvert Dimensions Deck Elevation 1 585.00 Upstream Flowline 573.34 Downstream Flowline 573.00 Length 24' Number of Barrels 3 Span Rise 3.3 Hydraulic Results 51 The results provided by the hydraulic model indicate that in both post -project conditions the impacts are kept on site. There are rises in water surface elevation upstream of the proposed culvert. However, these rises dissipate within the site and the water surface elevation is at pre -project elevation at the upstream end of the site. There are major fluctuations in channel velocity due to the proposed culvert. The channel is constructed with gabion basket channel walls, so the channel is able to 12 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 Foose Engineering & Development Services Saint Laurence Church Flood Study North Jones Branch J u ly 9, 2024 withstand erosive velocities which are generally considered above 6 fps. Tables 4-7 show the hydraulic results. A hydraulic workmap is shown on Figure S. Table 4 - Comparison of 100 yr EX Conditions WSELs Pre -Project Post-Project .n WS EleElevation 992 589.97 589.97 890 586.40 586.40 816 586.20 586.20 Difference (ft) 0.00 0.00 0.00 Existing Culvert N/A N/A N/A 716 585.15 585.19 0.04 621 584.09 584.03 -0.06 537 583.20 583.22 0.02 465 582.26 582.38 0.12 376 581.95 581.95 0.00 362 Proposed Culvert 317 581.68 581.69 0.01 N/A N/A 581.35 N/A 581.47 -0.12 259 581.46 581.41 -0.05 193 580.86 580.80 -0.06 Table 5 - Comparison of 100 yr EX Conditions WSELs with Prop. Culvert 13 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 Foose Engineering & Development Services Saint Laurence Church Flood Study North Jones Branch J u ly 9, 2024 Cross -Section 816 Existing Culvert 716 621 Pre -Project Post -Project (Prop. Culvert) 586.20 586.17 N/A N/A Difference (ft) -0.03 N/A 585.15 585.09 -0.06 584.09 584.21 0.12 537 583.20 584.69 1.49 465 582.26 584.75 2.49 376 581.95 584.50 2.55 362 581.68 584.01 2.33 Proposed Culvert N/A N/A N/A 317 581.47 581.08 -0.39 259 581.46 581.41 -0.05 193 580.86 580.80 -0.06 Table 6 - Comparison of 700 yr EX Conditions Channel Velocities Cross -Section Pre -Project Velocity (ft/s) Post -Project Velocity (ft/s) Difference (ft/s) Existing Culvert 14 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 Foose Engineering & Development Services Saint Laurence Church Flood Study North Jones Branch J u ly 9, 2024 Cross -Section Pre -Project Velocity (ft/s) Post -Project Velocity (ft/s) Difference (ft/s) Proposed Culvert Table 7 - Comparison of 100 yr EX Conditions Channel Velocities with Prop. Culvert -Project Pre(Pro Velocity (ft/s) Velocity (ft/s) Difference 992 3.07 3.07 0.00 890 14.13 14.13 0.00 816 9.33 9.30 0.03 Existing Culvert N/A N/A N/A 716 9.26 9.33 0.07 621 10.73 10.39 -0.34 537 10.83 7.17 -3.66 465 10.83 5.80 -5.03 376 9.05 6.09 -2.96 362 9.42 7.86 -1.56 15 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 Foose Engineering Saint Laurence Church Flood Study & Development Services North Jones Branch J u ly 9, 2024 16 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 No Text Foose Engineering & Development Services 4.0 Conclusion Saint Laurence Church Flood Study North Jones Branch J u ly 9, 2024 The post -project analysis was split into two conditions. The first incorporated the proposed grading and the second incorporated proposed grading and a proposed culvert. In both conditions the proposed improvements and changes cause some onsite changes in water surface elevations and changes in channel velocities. As demonstrated bythe hydraulic analysis in Section 3.0, neither post -project conditions cause adverse impacts offsite. The water surface elevation rises have dissipated by the upstream boundary of the site. 18 4625 Greenville Ave, Suite 305, Dallas, TX 75206 - (214) 986-2283 w STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 259 0 50 100 150 200 250 300 350 Station (ft) Legend WS PF 1 ■ Ground • Bank Sta STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 992 Legend WS PF 1 ■ Ground • Bank Sta 0 50 100 150 200 250 Station (ft) STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 890 Legend WS PF 1 ■ Ground A Ineff • Bank Sta 0 50 100 150 200 Station (ft) m STLaunenoaChuroh P|un:10OyrE)( 7/8/2024 River = River 1 Reach = Reach 1 RS = 816 586 578 0 20 40 60 80 100 120 140 160 180 STLaurenceChurch Plan: 100yrEX 7/8/2024 River River 1 Reach Reach 1 RS = 765 CuIv 588- Legend --------- ------------------- --------- I --------- --- ---------- WS PF 1 . .......... .......... .......... ........ ......... ......... .......... ......... ... ...... .......... .......... Ground ......... .......... .......... ......... ......... .......... ....... ...... Ineff. ---------- ---------- --------- --------- ---------- ------------------ -------------------- ---------- ---------- -- -- ---- ---------- ---------- --------- Bank Sta 586 - . ---------- -------------------- .......... .......... ----------- \ -------- ..................... ---------- -------------------- ....... .......... ---------- ...................... ---------- --------- ... .................. ---------- ------------- .......... .......... ------ ---------- ......... .......... -------------------- ......... I . ......... ---------- ..................... - 584- - . ............ --------------------- .......... ......... ---------- --------- ......... ........ ---------- - -------- .................... .......... ......... .......... ...... ... ......... .......... -------------------- ---------- --------- ---------- ------- --------- ---------- --------- --------- ........ ......... ---------- ........ ......... ......... .......... ...................... -------------------- .......... ---------- .......... --------- ---------- .......... ---------- .......... ---------- --------- .......... .......... --------- ----- ---- ......... ........ . --------- ---------- ......... .......... ---------- .......... ---------- ......... . - 582- .......... ---------- .......... ---------- .......... ......... ---------- --------- .......... .......... ---------- ---------- ........ . : .......... - ------ I ----------- -------------------- ......... .......... ---------- .................... --------- ---------- .......... ---------- ......... --------- LU - ---------- ---------- --------- ---------- ---------- -------------------------- ---------- --------- ----------- ---------- ---------- A ---------- --------- .......... .......... ......... .......... .......... ......... .................... .......... ......... - 580-- ---------- ------- ------ ------------------- --------- -------- ---------- --------- I ----------- ---------- --------- --------- ---------- .......... --------------------- ......... ---------- --------- - 578-- - ---------- ------- ---------- ------------------ .......... .......... ......... ..... ----------- -------------------- ......... .......... ---------- ...................... ---------------------- .......... ---------- .......... ---------- -- ----------------- ---------- ......... .......... --------------------- ......... I .......... ---------- .......... ---------- ......... - 576 --------------------- i ---------- --------- ---------- ............. --------------------- .............. --------------------- ......... ---------- --------- ......... .......... --------- ---------- .................... ---------------------- .......... ---------- ......... --------- 0 20 40 60 80 100 120 140 IbU 180 Station (ft) STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 716 Legend WS PF 1 ■ Ground A Ineff • Bank Sta 0 50 100 150 200 Station (ft) w STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 621 0 20 40 60 80 100 120 140 160 180 Station (ft) Legend WS PF 1 ■ Ground • Bank Sta STLaunenoaChuroh P|un:10OyrE)( 7/8/2024 River = River 1 Reach = Reach 1 RS = 537 dJZ/ 574 0 50 100 150 200 250 w STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 465 0 50 100 150 200 250 300 Station (ft) Legend WS PF 1 ■ Ground • Bank Sta STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 376 Legend WS PF 1 ■ Ground • Bank Sta 0 100 200 300 400 500 Station (ft) STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 362 Legend WS PF 1 ■ Ground • Bank Sta 0 100 200 300 400 500 Station (ft) STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 317 588 Legend WS PF 1 ■ Ground • Bank Sta 586 584 582 c 580 w 578 576 574 572 0 100 200 300 400 500 600 Station (ft) w STLaurenceChurch Plan:100yrEX 7/8/2024 River = River 1 Reach = Reach 1 RS = 193 0 50 100 150 200 250 300 350 400 Station (ft) Legend WS PF 1 ■ Ground • Bank Sta Plan: Prop Culvert River 1 Reach 1 RS: 343 Culv Group: Culvert #1 Profile: PF 1 Q Culv Group (cfs) 2113.80 Culv Full Len (ft) 24.00 # Barrels 3 Culv Vel US (ft/s) 12.58 Q Barrel (cfs) 704.60 Culv Vel IDS (ft/s) 12.58 E.G. US. (ft) 584.90 Culv Inv El Up (ft) 573.35 W.S. US. (ft) 584.01 Culv Inv El Dn (ft) 573.25 E.G. IDS (ft) 582.74 Culv Frctn Ls (ft) 0.13 W.S. IDS (ft) 581.08 Culv Exit Loss (ft) 0.81 Delta EG (ft) 2.16 Culv Entr Loss (ft) 1.23 Delta WS (ft) 2.93 Q Weir (cfs) E.G. IC (ft) 584.82 Weir Sta Lft (ft) E.G. OC (ft) 584.90 Weir Sta Rgt (ft) Culvert Control Outlet Weir Submerg Culv WS Inlet (ft) 580.35 Weir Max Depth (ft) Culv WS Outlet (ft) 580.25 Weir Avg Depth (ft) Culv Nml Depth (ft) Weir Flow Area (sq ft) Culv Crt Depth (ft) 6.22 Min El Weir Flow (ft) 585.01 w STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 259 0 50 100 150 200 250 300 350 Station (ft) Legend WS PF 1 ■ Ground • Bank Sta STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 992 Legend WS PF 1 ■ Ground • Bank Sta 0 50 100 150 200 250 Station (ft) STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 890 Legend WS PF 1 ■ Ground A Ineff • Bank Sta 0 50 100 150 200 Station (ft) m 8TLaunenoaChumh Plan: Prop 100yr_Cu|vart 5/1/2025 River = River 1 Reach = Reach I RS = 816 578 0 20 40 60 80 100 120 140 160 180 STLaurenceChurch Plan: Prop 1 00yr—Culvert 5/1/2025 River River 1 Reach Reach I RS = 765 CuIv 588- Legend --------- ------------------- --------- I --------- --- ---------- WS PF 1 . .. .................. ............. ......... ......... .......... ......... ... ...... .......... .......... Ground ......... .......... ......... ......... ......... .......... ....... ...... Ineff ---------- ---------- --------- --------- ---------- -------------------- -------------------- ---------- ---------- -- -- ---- ---------- ---------- --------- Bank Sta 586 - . ......... ----------- .......... - --------- .......... ----------- ------------------- .................... ---------- .......... --------------------- .................... ---------- ---------- ....... ..................... ---------- --------- ....... ........... .......... -- ------ ---------- ......... .......... --------- ---------- .................... -------------------- .......... - 584- - . ............ ---------- ---------- .......... ---------- --------- ..... ---------- - -------- .................... .......... ......... .......... ...... ... ......... .......... -------------------- -------------------- ---------- ------- --------- ---------- --------- I ---------- ........ ......... ---------- ........ ......... ......... .......... ......... I .......... --------- I ----------- .......... ---------- ......... --------- ---------- .......... ---------- .......... ---------- --------- .......... --------- ----- ---- ........ . --------- ---------- ......... .......... ---------- .......... ---------- .......... . - 582-- .......... ---------- .......... ---------- .......... ....... --- ---- ---------- .......... .......... --------- ---------- ....... . ......... - ------ I ----------- -------------------- ......... .......... ---------- .................... --------- ------- .......... ------- .......... --------- LU- ---------- ---------- ---------- --------- ---------- ---------- ------ -------------------- ---------- --------- ---------- ---------- ---------- A ---------- --------- .......... .................... .......... .......... .................... ......... I .......... .......... .......... .......... ......... - 580-- - ---------- ---------- ------ ---------- ---------- --------- -------- ---------- --------- I ----------- ---------- --------- --------- 4 ---------- .......... --------- ---------- ......... .......... ---------- .......... ---------- .......... - 578- - . ---------- ------- ----------------------------- .......... ......... ..... -------------------- ........ ......... .......... --------- ---------- ..................... --------- ----------- .......... ---------- .......... ---------- -- ----------------- .................. ---------- ......... .......... --------------------- ......... I .......... ---------- .......... ---------- .......... 576 -------------------- ---------- --------- --------- ---------- ............. -------------------- ..................... ---------- --------- .......... ......... ---------- --------- ......... .......... --------- ---------- ......... I .......... ---------------------- .......... ---------- ......... 0 20 40 60 80 100 120 140 160 180 Station (ft) STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 716 Legend WS PF 1 ■ Ground A Ineff • Bank Sta 0 50 100 150 200 Station (ft) w STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 621 0 20 40 60 80 100 120 140 160 180 Station (ft) Legend WS PF 1 ■ Ground • Bank Sta STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 537 Legend WS PF 1 ■ Ground • Bank Sta 0 50 100 150 200 250 Station (ft) w STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 465 0 50 100 150 200 250 300 Station (ft) Legend WS PF 1 ■ Ground • Bank Sta STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 376 Legend WS PF 1 ■ Ground A Ineff • Bank Sta 0 100 200 300 400 500 Station (ft) STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 362 Legend WS PF 1 ■ Ground A Ineff • Bank Sta 0 100 200 300 400 500 Station (ft) STLaurenceChurch Plan: Prop 1 00yr—Culvert 5/1/2025 River River 1 Reach Reach I RS = 343 CuIv 590- Legend WS PF 1 ----- ------- ------- ------- ------- ------- ------------- ------ ------- ------ ------- --------------- ----------------------- ------- ------ --------------- Ground Ineff 588 Bank Sta 586- 584- I ------- ------ -------- I ------- 582- -------- ....... ............... ....... ....... I ....... ....... .............. ............... LU 580 ------- ------ ------- ------- ------ ------- ------- ------ ------- ------ -------- 578- :1 -------------- ------- ------ ------- -------- I ------ 576- ....... ...... ....... ....... ...... ....... ....... ...... ....... ....... ...... 574- 4: ------- 4: ------- ------ 4 ------- 4 --------------- ------- --------------- --------------- 572 0 100 200 300 400 500 Station (ft) w STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 317 0 100 200 300 400 500 600 Station (ft) Legend WS PF 1 ■ Ground A Ineff • Bank Sta w STLaurenceChurch Plan: Prop 100yr_Culvert 5/1/2025 River = River 1 Reach = Reach 1 RS = 193 0 50 100 150 200 250 300 350 400 Station (ft) Legend WS PF 1 ■ Ground • Bank Sta STLaurenceChurch Plan:100yrEX 7/8/2024 River 1 Reach 1 >� 595 Legend -------------------- EG PF 1 WS PF 1 ............................ Crit PF 1 ■ Ground 590 585 ..............--------------------- c 0 m ... - w 580 575 570 0 200 400 600 800 1000 Main Channel Distance (ft) STLaurenceChurch Plan: Prop 100yr_Culvert 7/9/2024 River 1 Reach 1 595- Legend ----------------------- EG PF 1 WS PF 1 ............................ Crit PF 1 ■ Ground 590 585.................................... ..-- ..................... c 0 m _ w 580 } 575 570 0 200 400 600 800 1000 Main Channel Distance (ft)