This project consisted of the extension of a 24-inch waterline northward along the Capital of Texas Highway (Loop 360) from RM 2222 to the Davenport Ranch development. The project included the horizontal directional drilling (HDD) of the 24-inch waterline under the Colorado River in Lake Austin adjacent to the Pennybacker Bridge for the Capital of Texas Highway over Lake Austin.
The project was originally designed for Davenport Ranch Municipal Utility District but was carried out by Gray Engineering for the City of Austin in order to relieve dependency upon the Davenport Ranch development on its own independent water supply system when the city annexed it. The project was one of the early examples of horizontal directional drilling of this order of magnitude in the Central Texas Area.
The Loop 360 Water Supply Corporation is a member-owned private water company situated on the Westlake Peninsula. The Corporation serves over 600 customers including residences located in the hills of Westlake and along Lake Austin. Gray Engineering has represented the Corporation since the late 1990s.
The Corporation operates a 3 MGD surface water treatment plant that draws surface water directly from the Colorado River, treats it and distributes it through a series of storage tanks and distribution lines to its residential customers. The service area is dominated by large luxury residential housing that exerts above average water demands due to the size of the residences, a majority of which are located on multiple care lots.
The Cottonwood Creek regional water quality and detention pond improvement was unique in that it provided regional water quality and stormwater detention needs for approximately 261 acres in the upstream Cottonwood Creek watershed located in Williamson County.
The project was a joint venture funded by private development entities along with the City of Cedar Park, which all continue to collaborate on maintenance since its completion in 2008.
Features of the facility include the use of wet pond water quality best management practice and hike and bike facilities that are open to the community.
This project exemplifies what can be achieved through cooperation between landowners and municipalities when it comes to addressing stormwater detention and water quality issues over the North Edwards Aquifer on a regional basis.