For Water Subcommittee Meeting November 19, 2026
TO: Water Subcommittee Members
APPROVAL: Yazdan Emrani P.E., Director of Public Works and Utilities
Title
Staff Request Water Subcommittee Receive an Update on the Well City 3A/4A Project.
Body
RECOMMENDATION
Staff recommend that the Water Subcommittee receive an update on the Well City 3A/4A Project.
BACKGROUND
City Well 3A was drilled in 2010 with the goal of developing and additional source of supply from the Lytle Creek Basin. This well was dug to a depth of 875 feet and the static water level remains around 360 feet. After being drilled, the initial production reports showed elevated levels of arsenic. These elevated levels ultimately resulted in City Well 3A not being equipped and put into production. Subsequent pump test in 2015 indicated that if specific areas were packered (i.e. isolated), then arsenic level might drop. However, at that time, adequate water supplies and a lack of outside funding resulted in the project not moving forward.
ANALYSIS/DISCUSSION
As water supplies have changed over the past ten years, combined with some received grant funding, City Well 3A was reconsidered to be put into production. The City received $2 million from the US Bureau of Reclamation (USBR) and authorized RWS/Veolia to conduct updated water quality testing and treatment costs estimates. The recent test continued to exhibit high arsenic levels. Another complicating factor is site constraints. Because such elevated levels of arsenic were not anticipated at the time of drilling the well, it was located on a site that will not easily accommodate well head treatment equipment adjacent to the well. The arsenic treatment system would be located on a separate nearby parcel of land currently owned by the City at the Booster 2 Pump Station. An evaluation and cost estimate was prepared by RWS/Veolia and a treatment consultant. Their estimated project cost was $6 million to $11 million, resulting in an additional $4 million to $9 million of funding required from the City.
After evaluating the anticipated project cost, long term treatment costs and quantity of water with the City’s team, it was determined that the cost per acre foot of water would likely be very high. As a result, the City, RWS and Veolia looked at other water supply alternatives. Expanding Well 4A was identified as a potential option. This project aims to increase water production at the existing well site through strategic equipment upgrades and infrastructure modifications. The primary approach involves lowering the pump assembly by 100 feet to optimize drawdown, upsizing the primary pump and motor and improving the overall system efficiency. The well itself has been determined to be sufficiently deep, eliminating the need for costly well modification work.
The Well 4A project encompasses modifications across six major categories: primary pumping equipment, electrical infrastructure, structural support systems, secondary pumping systems, disinfection, and regulatory compliance. All modifications have been carefully planned to work synergistically, ensuring that each component of the water delivery system can handle the increased production demands. Veolia’s estimate of this alternative project is $2.29 million, plus appropriate markups under the concession agreement. The lower construction cost will result in a lower cost per acre feet to produce this additional water.
City staff and consultants have met with the USBR to confirm that repurposing of the grant from Well 3A to 4A will be allowed. The City will still be required to provide matching funds from any grant amounts up to $2 million. However, the overall project and cost per acre feet are substantially lower. The well site aerial view is shown as Attachment 1. Veolia’s Well 4A Production Increase Project Memorandum is included as Attachment 2.
ATTACHMENTS
1. Well Sites - aerial view
2. Veolia’s Well 4A Production Increase Project Memorandum