Plaza Mexico Residences 3000 E Imperial Highway Lynwood, CA KPFF Job #

Transcription

1 WATER AND SANITARY SEWER STUDY Plaza Mexico Residences 3000 E Imperial Highway Lynwood, CA KPFF Job # October 16, 2017 PREPARED BY: KPFF Consulting Engineers 700 S Flower Street, Suite 2100 Los Angeles, California T (213)

2 TABLE OF CONTENTS I. INTRODUCTION... 1 II. III. IV. EXISTING CONDITION... 2 SEWER CAPACITY CALCULATIONS...2 WATER CAPACITY CALCULATIONS...5 EXHIBITS Exhibit 1 Site Plan APPENDICES Appendix A Appendix B Appendix C Bentley FlowMaster Hydraulic Calculations Sewer Flow Gauging Data Fire Flow Test Water and Sanitary Sewer Study KPFF Consulting Engineers Plaza Mexico Residences Job # Lynwood, CA October 16,

3 I. INTRODUCTION The purpose of this study is to analyze the capacity of existing water and sanitary sewer infrastructures adjacent to the proposed Plaza Mexico Residences project site. The project consists of a mixed-use residential development with 4 stories of residential units over a twostory concrete parking structure on grade. The first floor includes 26,200 square feet of restaurant and retail spaces. The scope of the new construction is approximately 156,816 square feet or 3.6 acres. An aerial photograph of the project site is shown below. Imagery from Google Earth Water and Sanitary Sewer Study Plaza Mexico Residences Lynwood, CA KPFF Consulting Engineers Job # October 16,

4 II. EXISTING CONDITION The existing water and sanitary sewer services to and from the project site are mainly owned and operated by the City of Lynwood. Exhibit 1 shows the size of the existing water and sewer lines and the direction of flow within the vicinity of Plaza Mexico Residences project. The existing water mains are 6 in Imperial Highway, 12 in State Street, and 12 in Beechwood Avenue. The existing sanitary sewer system serving the proposed Plaza Mexico Residences is made up of a combination of 8-inch diameter vitrified clay pipe branch lines in Beechwood Avenue and Imperial Highway lines and a 24-inch diameter Los Angeles County trunk line located in State Street. The general direction of sewer conveyance from the project site is shown in Exhibit 1. III. SEWER CAPACITY CALCULATIONS US3 conducted sewer gauging studies at four manholes located in Imperial Highway, State Street and Beechwood Avenue (see Exhibit 1) during an eight day period from 9/28/2017 to 10/4/2017. The summary of the sewer gauging results is shown on Table 1 below. See Appendix B for the complete sewer gauging data. Table 1 - Sewer Gauging Study Results Pipe Location US3 ID Diameter (in) Pipe Slope Flow Direction Maximum Measured Flow (gpm) Minimum Measured Flow (gpm) Beechwood Site % West State & Beechwood State & Imperial Hwy Site % South Site % South Imperial Hwy Site % East The capacity of existing sanitary sewer pipes was calculated using Bentley FlowMaster hydraulic modeling software. For the sewer pipes equal to or less than 15 in diameter, the hydraulic capacity was calculated based on them maximum d/d (flow depth versus diameter) ratio of 0.5. For the sewer pipes greater than 15 in diameter, the hydraulic capacity was calculated based on them maximum d/d (flow depth versus diameter) ratio of The summary of the sewer capacity calculation is shown on Table 2. See Appendix A for software output. The total available sewer capacity at the project site is estimated to be gallons per minute. Water and Sanitary Sewer Study KPFF Consulting Engineers Plaza Mexico Residences Job # Lynwood, CA October 16,

5 Table 2 Sanitary Sewer Hydraulic Calculation Summary Diameter (in) Design Capacity (gpm) Existing Max Flow (gpm) Existing Max Depth (in) Existing % Full Available Capacity (gpm) Site 1: Beechwood % Site 2: State & Beechwood Site 3: State & Imperial Highway Site 4: Imperial Highway 1 Hydraulic Capacity based on d/d ratio of Hydraulic capacity based on d/d ratio of US3 identified 2 of sediments in the sewer line % % % 41.3 TOTAL GPM Using Los Angeles Bureau of Engineering sewer generation factors, the average daily sanitary sewer of the proposed development is estimated to be 77,726 gallons. The breakdown of sewer generation calculation is shown in Table 2. With peaking factor of 2.64, the peak flow is estimated to be 205,196 gallons per day (or 142 gallons per minute), and it is approximately 15% of the available sewer capacity in the adjacent sewer infrastructures. Table 3 - Sewer Generation Calculations Usage Area / Units Total Flow Peak Flow Sewer Generation (gallons per (gallons per Factor day) day) Retail 13,886 SF 300 GPD / 1000 SF 4,166 GPD 10,998 GPD Restaurant 12,314 SF or 30 GPD / seat 24,600 GPD 820 seats 1 64,944 GPD Residential Studio 3 units 80 GPD / unit 240 GPD 993 GPD Residential 1 bed 170 units 120 GPD / unit 20,400 GPD 53,856 GPD Residential 2 bed 167 units 160 GPD / unit 26,720 GPD 70,712 GPD Residential 3 bed 8 units 200 GPD / unit 1,600 GPD 4,224 GPD TOTAL ,726 GPD 205,196 GPD 54 GPM 142 GPM 1 15 sq. ft per seat used to estimate seat count 2 =2.64. Water and Sanitary Sewer Study KPFF Consulting Engineers Plaza Mexico Residences Job # Lynwood, CA October 16,

6 IV. WATER CAPACITY CALCULATIONS Two public fire hydrants were tested by City of Lynwood for fire flow availability. Please refer to Appendix C. Although both hydrants are located on Imperial Highway, the first hydrant is connected to the 6 main, and the second hydrant is connected to the 12 main. The static pressures were measured at 54 psi and 57 psi. The maximum available flows at 20 psi were estimated to be 2,270 gallons per minute and 2,678 gallons per minute, respectively. Based on the preliminary plumbing design, the total water demand for the Plaza Mexico Residences project is 800 gallons per minute. Using the available flow-pressure data of the 6 main as the basis, the available pressure at 800 gallons per minute is calculated to be 49 psi. Please refer to the graph below. Fire Flow Graph for 6 Water Main in Imperial Highway Water and Sanitary Sewer Study KPFF Consulting Engineers Plaza Mexico Residences Job # Lynwood, CA October 16,

7 EXHIBIT 1: SITE PLAN

8 38 x 26 NADEL RESIDENTIAL & COMMERCIAL INC 1990 S. BUNDY DRIVE SUITE 400 LOS ANGELES, CA T F LOS ANGELES LAS VEGAS PROFESSIONAL STAMP(S): NOT FOR CONSTRUCTION CONSULTANT: 700 South Flower Street Suite 2100 Los Angeles, CA O: F: CLIENT: 3000 E. IMPERIAL, LLC 6940 BEACH BLVD., SUITE D-501 BUENA PARK, CA x x 24 NO PARKING 60 x x 24 PROJECT: PLAZA MEXICO RESIDENCES VAN NO PARKING VAN NO PARKING VAN NO PARKING PROJECT ADDRESS: 3000 E. IMPERIAL HIGHWAY LYNWOOD, CA NO HC PARKING HC PUBLIC AGENCY SUBMITTAL: ISSUED FOR BIDDING: - N/A F. DRAIN F. DRAIN F. DRAIN F. DRAIN F. DRAIN ISSUED FOR CONSTRUCTION: N/A F. DRAIN F. DRAIN F. DRAIN F. DRAIN 62 x 26 F. DRAIN 62 x x x x 23 REVISIONS: ISSUE DESCRIPTION: NO.: ISSUE DATE: 10/03/ % DESIGN DEV. NADEL PROJECT : PROJECT DATE: ISSUE: UTILITY PLAN DRAWING TITLE: C1.50 ALL DRAWINGS AND WRITTEN MATERIAL APPEARING HEREIN CONSTITUTE THE ORIGINAL AND UNPUBLISHED WORK OF THE ARCHITECT AND THE SAME MAY NOT BE DUPLICATED, USED OR DISCLOSED WITHOUT THE WRITTEN CONSENT OF THE ARCHITECT. Copyright 2017, NADEL RESIDENTIAL & COMMERCIAL INC. ALL RIGHTS RESERVED. Oct 03, :12pm

9 APPENDIX A: HYDRAULIC CALCULATIONS A.1. Beechwood 8 Sanitary Sewer Capacity

10 A.2. State Street 24 Sanitary Sewer Capacity

11 A.3. State & Imperial Highway 8 Sanitary Sewer Capacity

12 A.4. Imperial Highway 8 Sanitary Sewer Capacity

13 APPENDIX B: SEWER FLOW GAUGING DATA

14 Site Report Confidential Proprietary Information M+D Properties ~2940 Beechwood Av Site 1 Beechwood MH Manhole No. 1 Access: Manhole is located in the center of the street. System Type: Sanitary X Storm Install Date: 9/27/2017 Map Flow Meter Meter Depth: 67" Map Coordinates: , Slow open channel hydraulics Avg Velocity Avg Measured Level Multiplier 0.4 fps 0.125" 1 Gas O2 H2S CO LEL Technology Notes Settlement of normal system solids noted in MH trough. Traffic Safety Used cones & signs in accordance with approved traffic control plan. Land Use Residential Commercial Industrial Trunk X Traffic Plan Manhole Depth Monitored Pipe Size Inner Pipe Size (In/Out) Pipe Shape Pipe Condition Manhole Material Silt Velocity Profile Data Velocity Profile Taken Sensor Offset Sensor Dist. to Crown Sensor Direction Flow Heading 82" 8" 8"/8" Round Good Brick, painted 0 * D 14.52" 6.52" Upstream West

15 Meter Site Document M+D Properties Site 1 Beechwood MH ~2940 Beechwood Av Site Manhole During Install Installation Process Installed MH Condition

16 Velocity (fps) Level (in) Flow (gpm) Average RainFall Inches Maximum Minimum /5/2017 5:02:04 PM

17 Velocity (fps) Level (in) Flow (gpm) Average RainFall Inches Maximum Minimum /5/2017 5:02:04 PM

18 9/27/2017 thru 10/5/ /5/2017 5:02:04 PM

19 Site Report Confidential Proprietary Information M+D Properties ~11201 State St Site 2 State & Beechwood MH Access: Manhole is located in the southbound lanes within the intersection of State St & Beechwood Av. System Type: Sanitary X Storm Manhole No. 2 Install Date: 9/27/2017 Map Flow Meter Meter Depth: 102" Map Coordinates: , Moderate open channel hydraulics Avg Velocity Avg Measured Level Multiplier 3.33 fps 6.75" 1 Gas O2 H2S CO LEL Technology Notes Laterals entering MH from east & west; no flow was noted from either during install or removal. Traffic Safety Used arrow board, barricades, cones & signs in accordance with approved traffic control plan. Land Use Residential Commercial Industrial Trunk X Traffic Plan Manhole Depth Monitored Pipe Size Inner Pipe Size (In/Out) Pipe Shape Pipe Condition Manhole Material Silt Velocity Profile Data Velocity Profile Taken Sensor Offset Sensor Dist. to Crown Sensor Direction Flow Heading 133" 24" 24"/24" Round Good Brick 0 * D 31.08" 7.08" Downstream South

20 Meter Site Document M+D Properties Site 2 State & Beechwood MH ~11201 State St Site Manhole Before Install Installation Process Installed

21 Velocity (fps) Level (in) Flow (gpm) Average RainFall Inches Maximum Minimum /5/2017 5:03:10 PM

22 Velocity (fps) Level (in) Flow (gpm) Average RainFall Inches Maximum Minimum /5/2017 5:03:10 PM

23 9/27/2017 thru 10/5/ /5/2017 5:03:10 PM

24 Site Report Confidential Proprietary Information M+D Properties ~2991 E. Imperial Hwy Site 3 State & Imperial MH Manhole No. 3 Access: Manhole is located in front of the eastbound left turn lane within the intersection of State St & Imperial Hwy. System Type: Sanitary X Storm Install Date: 9/27/2017 Map Flow Meter Meter Depth: 71" Map Coordinates: , Slow open channel hydraulics Avg Velocity Avg Measured Level Multiplier 0.5 fps 5.20" 1 Gas O2 H2S CO LEL Technology Notes Bend within MH; the larger pieces of brick were removed from the trough prior to monitoring. Traffic Safety Used arrow board, barricades, cones & signs in accordance with approved traffic control plan. Land Use Residential Commercial Industrial Trunk X Traffic Plan Manhole Depth Monitored Pipe Size Inner Pipe Size (In/Out) Pipe Shape Pipe Condition Manhole Material Silt Velocity Profile Data Velocity Profile Taken Sensor Offset Sensor Dist. to Crown Sensor Direction Flow Heading 86" 8" 8"/8" Round Poor Brick, painted but crumbling 2" * D 15.16" 7.16" Downstream South

25 Meter Site Document M+D Properties Site 3 State & Imperial MH ~2991 E. Imperial Hwy Site Manhole Before Install Debris Removal Sensor Installed Installed MH Condition

26 Velocity (fps) Level (in) Flow (gpm) Average RainFall Inches Maximum Minimum /5/2017 5:03:36 PM

27 Velocity (fps) Level (in) Flow (gpm) Average RainFall Inches Maximum Minimum /5/2017 5:03:36 PM

28 9/27/2017 thru 10/5/ /5/2017 5:03:36 PM

29 Site Report Confidential Proprietary Information M+D Properties ~2934 E. Imperial Hwy Site 4 Imperial MH Manhole No. 4 Access: Manhole is located in the center median lane. System Type: Sanitary X Storm Install Date: 9/27/2017 Map Flow Meter Meter Depth: 65" Map Coordinates: , Slow open channel hydraulics Avg Velocity Avg Measured Level Multiplier 0.33 fps 1.125" 1 Gas O2 H2S CO LEL Technology Notes Settlement of normal system solids noted in MH trough. Traffic Safety Used barricade, cones & signs in accordance with approved traffic control plan. Land Use Residential Commercial Industrial Trunk X Traffic Plan Manhole Depth Monitored Pipe Size Inner Pipe Size (In/Out) Pipe Shape Pipe Condition Manhole Material Silt Velocity Profile Data Velocity Profile Taken Sensor Offset Sensor Dist. to Crown Sensor Direction Flow Heading 80" 8" 8"/8" Round Fair Brick, painted but crumbling 0 * D 14.83" 6.83" Upstream East

30 Meter Site Document M+D Properties Site 4 Imperial MH ~2934 E. Imperial Hwy Site Manhole Before Install Installation Process Installed MH Condition

31 Velocity (fps) Level (in) Flow (gpm) Average RainFall Inches Maximum Minimum /5/2017 5:04:21 PM

32 Velocity (fps) Level (in) Flow (gpm) Average RainFall Inches Maximum Minimum /5/2017 5:04:21 PM

33 9/27/2017 thru 10/5/ /5/2017 5:04:21 PM

34 APPENDIX C: FIRE FLOW TEST

35 *... PART Il-A %/aen.c2 C I& P r INFORMATION ON FlRE FLOW AVAILABILITY (To be completed by Water Purveyor) Location Hydrant Number Distance from Size of 47" Nearest Property Line Size of Hydrant C X Y % ~ ~ ~ main ~ 6" Static PSI 5" Residual PSI ys Orifice size lh pitot ZS? Fire Flow at 20 PSI?--! 2fl Duration 2 #s Flow Test Date I Time?d?//k ~ ' Location -me - - LVY PQ C 6 L 'a & a Llh Hydrant Number Distance from Size of Nearest Property Line # Size of main 1 " Static PSI 57 Residual PSI * Orifice size 2 '/z Pitot 7% Fire Flow at 20 PSI 2; bt8 Duration Flow Test Date I Time ~!9 Location //* /.Iw* a Hydrant Number Distance from Size of Nearest Property Line Size of Hydrant Water main Static PSI Residual PSI Orifice size Pitot Fire Flow at 20 PSI Duration Flow Test Date I Time PART Il-B SPRINKLERED BUILDINGSIPRIVATE FIRE HYDRANTS ONLY Detector Location (check one) Above Grade Below Grade Either Backflow Protection Required (Fire S~rinklerslPrivate Hvdrant) (check one) yes No Minimum Type of Protection Required (check one) U Single Check Detector Assembly Double Check Detector Assembly Reduced Pressure Principle Detector Assembly 8'11 s 117 Date ' This Information is Considered Valid for Twelve Months Fire Department approval of building plans shall be required prior to the issuance of a Buildinq Permit by the jurisdictional Building Department. Any deficiencies in water systems will need to be resolved by the Fire Prevention Division & prior to this department's approval of building plans.