The Sierra Pines Regional Water Treatment Facility project is scheduled for construction completion in June 2029. The timeline comes from a Tuolumne Utilities District board record dated May 26, 2026.

What the schedule shows

The project schedule lists several design checkpoints after the August milestone. It calls for 60% design completion in December 2026, 90% design in March 2027 and 100% design in June 2027.

The planned design work includes site civil work, building systems and treatment processes. The record also identifies a public project meeting in Twain Harte scheduled for May 27, 2026, one day after the board record.

The August 30% design and cost estimate should be understood as a scheduled project step, not a confirmed completed milestone. The available record does not show the August estimate or a current total project cost. It also does not identify a final construction contract.

What it means for Twain Harte

The facility is described as a regional water-treatment project presented to the Tuolumne Utilities District board. That makes the project relevant to the Twain Harte area’s water infrastructure, although the available excerpts do not specify the facility’s exact address or the precise portion of service that would benefit Twain Harte.

Residents and businesses may ultimately gain improved treatment capacity and reliability, but the sources do not provide a specific capacity increase or guarantee a particular benefit to customers. The advancing schedule also signals construction activity beginning with planned mass grading in fall 2026. The available record does not specify traffic, noise, service or other construction impacts.

Twain Harte Community Services District separately identifies water, sewer, fire and park services for the Twain Harte community. A separate environmental record covers a different Twain Harte water-system project intended to improve fire flow in pressure zones 4 and 6 through pipeline replacement, upsizing, relocation or abandonment.

That Sherwood distribution-system improvement project should not be confused with the Sierra Pines regional treatment facility. The Sierra Pines schedule’s next listed steps are the August 2026 design and cost-estimate milestone, the September groundbreaking target and fall mass grading, followed by the later design checkpoints and the June 2029 construction-completion target.