Land Use and Population Assumptions The Water Master Plan projects population growth through 2030 based on a 3.68% annual growth rate. The plan projects ultimate buildout at a population of 190,000. The water plan uses this growth projection to determine the need for additional source water. The Water Master Plan assumed future demands and growth based on the 2015 Future Land Use Plan (FLUP). Upon adoption of this comprehensive plan and the revised FLUP, the Water Master Plan should be updated to account for increased densities in specific locations related to this new FLUP. Also, the new place types in the FLUP allow for potential multi-story structures; the revised Water Master Plan should provide capital improvements designed to serve these
Water Supply Sources Pearland’s water system is served by both surface water and groundwater sources. The Water Master Plan lists groundwater supply capacities of 18.40 MGD and 16.0 MGD of surface water supply capacity. Currently, Pearland receives treated surface water of 10 MGD from the Gulf Coast Water Authority (GCWA) at Alice Water Plant and 6 MGD from the City of Houston at the Shadow Creek Plant. The Water Master Plan projects demands across the city and identifies required additional water sources such as the new 10 MGD capacity Surface Water Treatment Plant (SWTP) located at 3720 County Road 48 (Airline Road) and expanding the Alice Water Plant by 5 MGD to provide a total supply excess over the planning period. At the time of this comprehensive plan report, Pearland had designed the SWTP and engaged a Construction Manager at Risk (CMAR). The CMAR team was on schedule for completing the construction of the SWTP and related transmission system by summer 2023. The City of Pearland Wastewater Master Plan describes a program for reuse of treated wastewater effluent for beneficial uses such as irrigation, process water, or other applications. The reuse study identified 2025 projected average daily flows of 12 MGD and 16.31 MGD of potential irrigation water users who could potentially make use of the treated effluent. From a land use planning view, the comprehensive plan recommends promoting the use of reclaimed water and allocating space in the right- of-way for related infrastructure. Distribution System Coverage The existing water distribution system has been constructed largely between 1960 and 2010. The distribution system includes more than 540 miles of pipe ranging from 2-inch to 30-inch diameter. The majority (54%) of the water piping is 8-inch diameter. The primary pipe materials include approximately 87% polyvinyl chloride (PVC), 12%
transite, and 1% ductile iron. The City actively manages an ongoing pipe replacement program to replace the transite and ductile iron with PVC. Water Capacity and Storage Water storage is critical to the function of maintaining pressures in the water system. Pearland water system operates and maintains 14 ground storage tanks (GSTs) for a total GST capacity of 14.4 million gallons (MG). The system operates and maintains six elevated storage tanks (ESTs) for a total EST capacity of 4.5 MG. The Texas Commission on Environmental Quality (TCEQ) requires Pearland, under the alternative capacity requirement letter from February 15, 2019, to maintain the following production capacities: Î Total production capacity: 0.44 gallons per minute (gpm) per connection Î Total storage capacity: 148 gallons per connection Î EST capacity: 74 gallons per connection The Water Master Plan projected 62,420 connections at build out, which means TCEQ requires: Î Total production capacity: 27,464 gpm Î Total storage capacity: 9.24 MG Î EST capacity: 4.62 MG The existing water system includes 18.9 MG of water storage. Prior to the 2030 buildout, the water plan recommends construction of an additional 2.8 MG storage to meet the TCEQ requirements. Capital Improvements The Water Master Plan includes a five-year Capital Improvement Plan (CIP) describing projects that will maintain the service level of the water distribution system.
structures with adequate pressure and flow. WATER DEMAND PROJECTIONS
The Water Master Plan describes hydraulic modeling analysis comparing the local system demands to the available supply. Figure 5.2 from the master plan shows the need for the construction of additional supply sources to maintain pressure, storage, and flow through the system in normal, peak, and fire- flow scenarios.
FIGURE 5.2: SYSTEM WIDE SUPPLY AND DEMAND (2018-2030) Systemwide Potable Water Supply and Demand
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4.7
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40
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4.7
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1.3
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2018
2023
2030
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Existing Groundwater Supply
Existing Surface Water @ Alice WP
Existing Take or Pay Surface Water @ Shadow Creek WP
Planned Surface Water @ New SWTP
Planned Surface Water @ Alice WP
Existing Additional Available Surface Water @ Shadow Creek WP
Maximum Potable Water Demand (Based on 225 GPCD)
Source: August 2019 Pearland Water Master Plan
The Water Master Plan includes an analysis of the historical Average Day Demand (ADD) and Maximum Day Demand (MDD). The plan uses these historical and population projections to project overall water demand. The plan projects an ADD of 24 MGD when the population reaches 190,000.
PEARLAND COMPREHENSIVE PLAN 2040
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Chapter 5
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