WATER CALCULATION REPORT - Buena Park, California

APPENDIX K-1

WATER CALCULATION REPORT

WATER CALCULATION REPORT

For:

BEACH AND ORANGETHORPE

MIXED USED DEVELOPMENT PROJECT

CITY OF BUENA PARK

CALIFORNIA

June 03, 2008

PREPARED BY:

M:\2BEA040100\ENGR\DOCS\Report\water\WATER CALCULATION REPORT.doc

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)

.


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


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


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


Calculations

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


APPENDIX


REFERENCE MATERIAL

Documents

WATER CALCULATION REPORT - Buena Park, California