Water Transmission Mains Overview

Moving water from WTP4 to customers will be an important part of the project. The water transmission mains will be very large pipelines transporting water to storage reservoirs.

The Forest Ridge water transmission main is planned to be 48 inches in diameter, and will carry water from WTP4 to the Forest Ridge Reservoir located near Spicewood Springs Road and Capital of Texas Highway. The Jollyville water transmission main will be 84 inches in diameter, and will carry water from the plant to the Jollyville Reservoir located near US 183 and McNeil Road.

Both Forest Ridge and Jollyville water transmission mains are currently in the preliminary design phase. At the end of this phase a preferred route will be determined and presented to the public for comments.

Route Selection

The project is currently in the preliminary design phase to determine the best route for each water transmission main. In this phase the project teams will evaluate environmental factors, community impacts, cost, and constructability to determine the least environmentally sensitive and most efficient route for each water transmission main. This preliminary design phase should take approximately one year. At the end of which, the proposed routes for both Forest Ridge and Jollyville water transmission mains will be determined.

Construction Methods
Both tunneling and trenching are being considered as construction methods for the water transmission mains.

Tunneling

Tunneling is the construction process where machines are used to create a pathway for the water transmission main underground. Shaft locations or vertical tunnels connecting to the main water tunnel are necessary for this type of construction as entry and exit points. This type of construction is preferred and beneficial in environmentally sensitive zones as it does not disrupt the surface. Tunneling is the required construction method in the Balcones Canyonlands Preserve. This process is more expensive than trenching.

Public Meetings