City of Leander San Gabriel East Pump Station
Increasing Drinking Water Capacity in Response to Local Growth
Project Purpose
With continued exponential growth in the City, and large developments planned in the north and eastern areas, the City of Leander requires expansion of their distribution system and a new 1200 pressure plane to serve the area. The San Gabriel East Pump Station will pump from the existing 1127 pressure plane to the new 1200 plane created by the related Kauffman Loop Elevated Storage Tank (also designed by KFA). Based on updates to the City’s water models and growth projections, KFA determined that the required ultimate capacity of the new pump station was 25.9 million gallons per day. The initial project design consisted of three 4,500 gallons-per-minute pumps, and provided the infrastructure to add two future pumps to reach the ultimate capacity. The pump station was designed to be constructed within a masonry building.
Project Approach
KFA was retained by the City of Leander to plan, design, and provide construction administration for the pump station. In the planning stage, KFA updated the City’s system-wide water models in WaterCAD to determine the required capacity of the pump station for both the current need and ultimate build-out. We also oversaw surveying, geotechnical investigations, environmental, and archaeological investigations. Pump types, sizing, and layout options were discussed with City Staff; vertical turbine pumps were ultimately selected to limit the size of the proposed pump station building. Each pump is outfitted with variable frequency drives to allow for adjustable capacity during service area build-out. Since the pump station will provide water to furthest reaches of the system, it was determined that a chloramine booster station would be included in the design.
The KFA team prepared the final design and construction documents for the pump station, including 2,500 linear feet of 24 and 36-inch piping, site grading, pavement design, and drainage improvements. We then assisted the City with bidding, and construction administration. The site obtained by the City for this infrastructure was located on the side of a steep hill with limited developable space. This location required extensive grading and retaining walls, and efficient use of space to fit the proposed pump station and future elevated storage tank on the site.
Project Results
The pump station was placed online in August 2020.
This was an interesting and challenging project with numerous elements to be accounted for and addressed throughout design and construction. Site constraints dictated many of the design choices, from pump types to extensive use of retaining walls, as well as limiting impacts to an adjacent residential neighborhood.
Dale Murphy, PE, Project Manager
K Friese + Associates (KFA)