To: Members of the Castle Rock Water Commission
From: Mark Marlowe, P.E., Director of Castle Rock Water
Mark Henderson, P.E., Assistant Director
Roy Gallea, P.E., Engineering Manager
Matthew Hayes, P.E., Technical Engineering Manager
Josh Hansen, P.E., CIP Project Manager Supervisor
Aaron Stremel, Water Engineer
Title
Resolution Approving a Design Services Agreement between the Town of Castle Rock and Tetra Tech, for the Hillside Pump Station Upgrade Project [Castle Rock Heights]
Town Council Agenda Date: May 5, 2026
Body
________________________________________________________________________________
Executive Summary
The purpose of this memo is to request the Town Council approval of a Design Services Agreement (Attachment A) with Tetra Tech for design, engineering and bid support services for the replacement and upgrade of Hillside Pump Station and relevant distribution system piping. An assessment will be performed to evaluate pipeline alternatives for upgrade including a memorandum of the identified alignment. Staff recommends approval of the agreement between Castle Rock Water (CRW) and Tetra Tech for $583,575 with a 10% contingency for a total authorization of $641,932.50. Services are expected to begin upon execution of the contract and be completed Spring 2027.
Discussion
The Hillside Pump Station and associated transmission infrastructure are critical components of the Town’s potable water delivery system, conveying treated water from the Plum Creek Water Purification Facility (PCWPF) and the Meadows Water Treatment Facility in the Yellow Zone to the eastern portions of the system within the Blue Zone. The existing pump station, originally constructed in 1985, was designed to transfer water between storage facilities that have since been removed from the Town’s distribution system (Tank 1 and Tank 2), resulting in operations that no longer align with the current system configuration. The facility is currently limited to a single pump with an approximate design capacity of 800 GPM and discharges through approximately 2,100 linear feet of predominantly 8-inch pipeline with limited conveyance capacity. As system demands have increased and development has expanded within the Blue Zone, these facilities have become capacity-constrained, inefficient, and lack resilience, including the absence of on-site backup power. To address these deficiencies and support future system demands, the Town is advancing improvements to both the pump station and transmission infrastructure, including increasing firm pumping capacity and evaluating options to upsize or replace the existing conveyance system.
The objective of this project is to improve system capacity, reliability, and operational resiliency through the replacement of the Hillside Pump Station and the upgrade of the associated transmission main. The proposed pump station will be designed to provide up to 2,600 GPM firm capacity at approximately 450 feet of total dynamic head, while meeting current design standards and accommodating long-term operations and maintenance needs. Transmission improvements will include evaluation of alternatives to either upsize the existing 8-inch pipeline or construct a new 12-inch alignment extending from the pump station south along South Gilbert Street to the point of connection with the existing 12-inch distribution system. Work will include the following: an initial Alignment Evaluation Phase to assess feasible pipeline alternatives, a Design Phase consisting of survey and site investigation, identification of property lines and easements, preliminary through final design of the pump station and pipeline, preparation of TESC plans and technical specifications, coordination with local residents to address neighborhood considerations, and completion of required permitting.
A Request for Qualifications (RFQ) was advertised on Bidnet to procure qualified consultants for the 2026 pre-qualified consultants list for various Castle Rock Water Capital Improvement Projects. A project specific Request for Proposal (RFP) was issued to nine (9) of these pre-qualified consultants for this project from both the Water Infrastructure and Water Facility lists. Responses were received from six (6) firms. The following table shows the fee proposals received from the consulting firms assuming that full replacement of the pump station would be required:
|
Consulting Firm |
Total Cost |
|
Black & Veatch |
$1,183,135 |
|
Burns & McDonnell |
$699,894 |
|
Carollo |
$742,522 |
|
Consor |
No Proposal |
|
Dewberry |
$862,102 |
|
Hazen |
$762,629 |
|
HDR |
No Proposal |
|
Providence |
No Proposal |
|
Tetra Tech |
$583,575 |
Tetra Tech was selected by the evaluation committee to perform services for this project, and staff have determined that their proposed fee is reasonable. While proposal values ranged from approximately $580,000 to $1,200,000, all teams generally met the project scope. Tetra Tech’s proposal, however, best aligned with the requirements and intent of Castle Rock Water while also offering the lowest cost. Additionally, Castle Rock Water has an established working relationship with Tetra Tech that has consistently proven to be collaborative and successful.
Budget Impact
The Tetra Tech proposal fee is $583,575. Staff requests an additional $58,357.50 (Town-managed 10% contingency) be authorized for a total project authorization of $641,932.50. The project will be funded from the Distribution System Upgrades Fund (210-4275-442.75-38) and managed by a budget transfer from the Tank 8B Fund (210-4275-442.79-36) after 2025 to 2026 carry-forward.
|
Project Number |
Account Name |
Account Number |
Contract Amount |
Contingency |
Authorization Amount |
2026 Budget |
|
260007 |
Distrib System Upgrades |
210-4275-442.75-38 |
$583,575.00 |
$58,375.50 |
$641,932.50 |
$0 |
Proposed Motion
“I move to recommend to Town Council approval of the Resolution as presented”
Attachments
Attachment A: Resolution (Not Attached)
Exhibit 1: Agreement (Not Attached)
Attachment B: Area Map
Attachment C: Location Map