SPDSS_Task66-2_CollectDevelopMunicipalIndustrialConsumptiveUseEstimates

• Title: SPDSS Task 66.2 - Collect and Develop Municipal and Industrial Consumptive Use Estimates
• Description: This memorandum presents the general approach used to develop municipal and industrial consumptive use for the CU and Losses Summary Report and estimate indoor and outdoor water demands, consumptive use, and return flows for SPDSS modeling efforts.
• Decision Support - Doc Type: Task Memorandum
• Date: 11/14/2007
• DSS Category: Consumptive Use
• DSS: South Platte
• Basin: South Platte
• Contract/PO #: C153954
• Grant Type: Non-Reimbursable
• Bill Number: SB01-157, HB02-1152, SB03-110, HB04-1221, SB05-084, HB06-1313, SB07-122
• Prepared By: Leonard Rice Engineering

The Colorado Water Conservation Board (CWCB)-sponsored Surface Water Supply Initiative
(SWSI) completed a comprehensive effort involving data and literature review to estimate
appropriate per capita water demand estimates for the year 2000 for municipalities and rural
water users throughout the State of Colorado. These demand estimates represent a baseline level
in the SWSI report upon which future water demand was compared against future water supply
options. This information is summarized in the Statewide Water Supply Initiative Report,
November 2004, particularly Chapter 5 -Projected Water Use and Appendix E -Statewide
Municipal and Industrial and Self-Supplied Industrial Water Demand Projections. Information
for this report, along with information regarding municipal ground water use, was considered in
this task.
APPROACH
The approach to the following tasks carried out for this effort is summarized below. More details
regarding the approach are presented along with the Results and summarized in the attached
tables and figures.
1. Gather Population Data
2. Estimate Historical Municipal and Industrial Water Demands
3. Estimate Historical Municipal and Industrial Consumptive Water Use
4. Recommend Preliminary SPDSS Model Locations and Modeling Approach for Key and
Aggregate Municipal Structures and Self-Supplied Industrial Structures
Data gathered from interviews carried out for the Task 3 and Task 5 efforts, along with review of
data from the SWSI effort and historical population data collected for the SPDSS Study Area,
were used to estimate the total municipal and industrial water demand and consumptive use over
time. The population data over time gathered for this effort were provided to the State database
administrator for incorporation into HydroBase (see Task 66.1 memo). These data have been
loaded into HydroBase. The annual population data were accessed via TSTooI for use in
developing historical demand input files.
Information regarding the interviews and sources used are summarized in the References section.
Limitations associated with available data and the methodology chosen for this analysis are
discussed in the Comments and Concerns section.
RESULTS
1. Population Data
There are two major sources of census data: U.S. Census Bureau and Colorado Department of
Local Affairs (DOLA). Census Bureau data are available from before 1950 through 2000,
published every ten years. Between the decennial census years, DOLA adjusts the Census
Bureau data every year to account for population changes in local communities. Population data
are available on an annual basis from DOLA for 1961 to present for counties and 1971 to present
for municipalities. Unincorporated populations within counties are estimated based on total
county population minus municipal populations within the county.
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