Aerial view of the Goleta Sanitary Sewage Treatment Plant, which serves IV, with the remains of Mescalitan island at left and UCSB in the distance. In September 2011 (while undergoing renovations), by Britta Gustafson (CC BY-SA).

Goleta West Sanitary District is a special district that provides wastewater collection and treatment for residents of Isla Vista and the West Goleta Valley. It runs a wastewater treatment plant between the airport and UCSB, on the site that used to be Mescalitan Island.

"Goleta West Sanitary District, which contracts with Goleta Sanitary District for sewage treatment, was initially formed as the Isla Vista Sanitary District in 1954. Expanding into western Goleta Valley, it became the Goleta West Sanitary District in 1989. Goleta West Sanitary District serves 32,000 customers in the Goleta Valley and in Isla Vista. An agreement was reached with the Goleta Sanitary District to treat Goleta West Sanitary District's wastewater. Approximately 40% of the processing by the Goleta Sanitary District is under the contract with the Goleta West Sanitary District. Although the district is Goleta Sanitary District’s biggest customer, it is only a customer and has no vote on GSD’s board." Santa Barbara Grand Jury: Goleta West Sanitary District (2004)

In 2008, Goleta West Sanitary was required to upgrade one of its treatment plants to a higher level called "full secondary". At the time, despite financial pressures, they stated "Goleta West Sanitary District has sufficient reserves to cover its $15 to $20 million share of treatment plant upgrade costs, and, therefore, does not need a rate increase to cover it"State Budget Problems Could Impact District (2008)

Goleta West Sanitary District is a sponsor of IV's Adopt-A-Block volunteer litter cleanup program.