water calculation report - buena park, california
TRANSCRIPT
WATER CALCULATION REPORT
For:
BEACH AND ORANGETHORPE
MIXED USED DEVELOPMENT PROJECT
CITY OF BUENA PARK
CALIFORNIA
June 03, 2008
PREPARED BY:
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TABLE OF CONTENTS
1. GENERAL DISCUSSION
a. Project Background
b. Demand Estimate
c. Hydraulic Modeling
d. Proposed Water Node Exhibit
e. Proposed Water Exhibit
2. CALCULATIONS
a. Existing Commercial and Residential Demand Calculation
b. Commercial and Residential Ultimate Demand Calculation
c. Proposed High Rise Mixed Used Project per Capita
3. APPENDIX
a. Water Atlas Map (City of Buena Park)
b. Water As-built Maps
4. REFERENCE MATERIAL a. City Buena Park 2005 Water Master Plan Study, Final Report (see City of
Buena Park for Report)
.
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GENERAL DISCUSSION
Project Background
The project site is 12.75 acres located at the northeast corner of Orangethorpe Avenue
and Beach Boulevard. 6.73 acres are vacant land surrounded by residential and
commercial buildings. The site is bounded by Beach Boulevard on the west,
Orangethorpe Avenue on the south, Brenner Avenue on the east, and Melrose Street on
the north. 18 single family residential lots and 7 commercial buildings exist on-site and
currently have a demand of approximately 12,108 gallons per day (gpd) estimated
average day water demand which is provided by city facilities located in the streets that
bound the project. The City of Buena Park 2005 Water Master Plan Study identifies the
undeveloped area located at the northeast corner Beach and Orangethorpe as commercial
land use (Entertainment Corridor Specific Plan).
Demand Estimates
The projects water demand can be calculated on the basis of estimated population and per
capita demands for residential land uses, and unit demand factors by acre for non-
residential land uses or from a direct analysis of facilities and fixtures for non-residential
land uses. However, the City of Buena Park does not maintain any standard unit demand
factors for specific types of land uses. The City of Buena Park 2005 Water Master Plan
Study dated February 2007 provides a water demand usage of 200 gallons per capita
daily (gpcd) that is calculated from the city population and total production records for
system wide demands, and not the consumption record. Water demands are not constant
within the service area, and therefore cannot simply be evenly distributed to all area of
the service area. Seasonal and daily variations in the water demands are accounted for by
adjusting Average Daily Demands (ADD) using a multiplier to simulate other demand
periods. Per the Center for Demographic Research, 3.44 persons per household reside in
the City of Buena in each single family home per December 2007 Population and
Housing Estimates by Jurisdiction. The high-density, multi-family housing units
proposed for the project would be smaller than many existing single-family residences in
the city that have 3 to 4 bedrooms. The proposed project units are smaller than many
homes in the city which have an average household size of 3.44 persons. Demands
estimated for this project are slightly higher than the demands estimated using a 3.44
persons per household because 3.44 is based upon a generalized census for community
or city including uses such as residential, commercial, office, hospital, hotel, irrigation,
industrial, and school etc.
Actual demands vary from user to user depending on many factors, but land use is one of
the primary determining factors for estimating water demand. A household ratio of 2 for
hotel units and 2.7 for condo units is consistent with downtown oriented development.
Therefore, for analysis in this EIR, a conservative estimate derived from many varieties
of single-family homes, condominium complexes and multi-family rental units found
thought Orange County and Los Angeles County of 2 persons per hotel unit and 2.7
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persons for condo unit was used in the study. The proposed development, which will
consist of a maximum of 1,000 condo/office units, 300 hotel rooms, and 355,000 square
feet of retail space will have an average day water demand (ADD) of approximately 514
gallons per minute (gpm) based on preliminary estimates using 200 gpd per capita for
domestic use, 190 gpd per 1,000 sf of retail area, and 5,000 gpd per acre (20% irrigated
area on a commercial site). Table 1 below shows water use estimates by proposed land
use type for the proposed project. Maximum day demand (MDD) and peak hour demand
(PHD) estimates are based on peaking factors from the City of Buena Parks 2005 Water
Master Plan Study of 1.6 and 2.4 times the ADD respectively. The estimated MDD is
rounded up to 900 gpm (1,296,000 gpd) and a total peak hour demand of 1,350 gpm
(1,944,000 gpd) to be conservative, see Table 2 Modeled Flow and Pressure.
Table 1
Water Demand Estimate
Area Name
Square
Feet Unit No. of Units
Capita per Unit Capita
Demand (gpd)
Demand (gpm)
Condo/Office Phase I DU 681 2.7 1839
367,740 255
Condo/Office Phase II DU 319 2.7 861
172,260 120
Hotel Room 300 2.0 600
120,000 83
Retail
355,000 1,000 SF 355 0 0 67,450 47
20% Irr @ 5000 gpd/acre 12.75 AC 2.55 0 0
12,750 9
Total Average Day Demand
740,200 514
The fire flow demand for each structure will be based on building square footage,
construction type, and the installation of automatic sprinkler systems. Building
construction type is unknown at this time as well as the use of sprinkler systems. To be
conservative, the highest fire flow demand of 8,000 gpm, from the California Fire Code
(Table A-III-A-1), was assumed for a flow duration of 4 hours. A minimum fire flow
pressure of 20 pounds per square inch (psi) will be required.
Hydraulic Modeling
The City’s current hydraulic water model was utilized for the analysis, with demand
estimates for the proposed project inserted at appropriate model nodes shown on the
attached figure. All model scenarios were simulated using year 2030 build-out
conditions. The model simulations include maximum day demand plus fire flow and peak
hour demand scenarios. Based on these preliminary modeling results, 12-inch pipelines
are recommended along Brenner Avenue and Melrose Street to provide adequate fire
protection. Any internal pipelines, running through the project site, that are used to
provide fire flow should also be sized at 12-inches. The existing 16-inch pipeline in
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Orangethorpe Avenue and 12-inch pipeline in Beach Boulevard as well as the
surrounding distribution system have adequate capacity.
Table 2 below shows modeled flows and corresponding pressures for the proposed 12-
inch water lines in Melrose and Brenner and the existing water lines on Beach and
Orangethorpe surrounding the site. Pipeline velocities in the vicinity of the site remain
below 5 feet per second during peak hour demand conditions and below 10 feet per
second under fire flow conditions, meeting typical design criteria provided in section 1.8
of the Master Plan Analysis and Design Criteria of the City of Buena Park 2005 Water
Master Plan Final Report.
Table 2 Modeled Flow and Pressure
Peak Hour Demand MDD plus Fire Flow
Node Flow (gpm) Pressure
(psi) Flow (gpm) Pressure
(psi)
1 450 63.0 2,300 52.7
2 450 62.6 2,300 52.2
3 450 63.1 2,300 61.2
4 - 62.7 2,000 60.9
Total 1,350 8,900
BUENA PARK WATER DEMAND STUDY
Area Name AREA (SF)
AREA
(ACRE)
WATER
DEMAND
(GPD/AC)
WATER
DEMAND
(GPD)
Flow
(GPM)
Peak
Factor Flow (cfs)
Undeveloped Land 293,469.00 6.73 - 0.00 0.00 -
Donut Express 5,500.00 0.13 2,500.00 315.51 0.22 0.00
Restaurant (Pizza) 10,850.00 0.25 2,500.00 622.42 0.43 0.00
Restaurant (Japenese) 38,188.00 0.88 2,500.00 2190.68 1.52 0.00
Gas/Service Station 11,325.00 0.26 2,500.00 649.67 0.45 0.00
Car Wash (recycling) 15,385.00 0.35 2,500.00 882.57 0.61 0.00
Motel (Orangethorpe) 8,700.00 0.20 2,500.00 499.08 0.35 0.00
Residential 149,730.00 3.44 1,650.00 5668.99 3.94 0.01
Hotel/Motel (Beach) 22,305.00 0.51 2,500.00 1279.54 0.89 0.00
TOTAL 12.75 12108.47 8.41 0.02
Area Name AREA (SF)
AREA
(ACRE)
WATER
DEMAND
(GPD/AC)
WATER
DEMAND
(GPD)
DEMAND
(GPM)
Peak
Factor Flow (cfs)
ECSP 293,469.00 6.73 2,500.00 16825.00 11.68 0.03
Donut Express 5,500.00 0.13 2,500.00 315.51 0.22 0.00
Restaurant (Pizza) 10,850.00 0.25 2,500.00 622.42 0.43 0.00
Restaurant (Japenese) 38,188.00 0.88 2,500.00 2190.68 1.52 0.00
Gas/Service Station 11,325.00 0.26 2,500.00 649.67 0.45 0.00
Car Wash (recycling) 15,385.00 0.35 2,500.00 882.57 0.61 0.00
Motel (Orangethorpe) 8,700.00 0.20 2,500.00 499.08 0.35 0.00
Residential 149,730.00 3.44 1,650.00 5668.99 3.94 0.01
Hotel/Motel (Beach) 22,305.00 0.51 2,500.00 1279.54 0.89 0.00
TOTAL 12.74 28933.47 20.09 0.04
Prepared: 01/07/2008
Existing Commercial and
Commercial and Residential Ultimate Damand Calculation
BUENA PARK WATER DEMAND STUDY
Proposed High-Rise Mixed-Used Project per Capita
Area Name Square Feet Unit
No. of
Units
Capita per
Unit Capita
Demand
per Unit
(gpcd)
Demand
(gpm) Flow (cfs)
Condo Phase I DU 681 2.7 1839 200 255 0.57
Condo Phase II DU 319 2.7 861 200 120 0.27
Hotel Room 300 2.0 600 200 83 0.19
Retail 355,000 1,000 SF 355 0 0 190 47 0.10
20% Irr @ 5000 gpd/acre 12.75 ac 2.55 0.00 0.00 5000 9 0.02
TOTAL ADD 514 1.15
Prepared: 05/05/2008