For the past week and a half I have been in Santa Barbara, CA, getting to know my new UCSB basketball teammates (freshmen!) and working out with the team as a whole. As the time approaches for me to return to Bozeman and complete my summer internship at the Project WET Foundation, I decided it would be interesting to profile Santa Barbara County’s source water system. At Project WET Foundation, this type of information contributes to a “water address.”
Credit: RJ Zaworski, used with permission.
The U.S. Environmental Protection Agency (EPA) offers an online tool for locating and defining a watershed address. The address consists of a watershed’s proper name and Hydrologic Unit Code (HUC)—a hierarchical string of numbers ranging from 2 to 16 digits that describes the location and identification of a hydrologic area. HUCs come from the U.S. Geological Survey (USGS), which has a nationwide system for watershed delineation based on surface hydrologic features.
Santa Barbara’s source water profile consists of multiple watersheds, namely the Santa Ynez Watershed 18060010 (northern highlighted watershed on map of CA on right) and the Santa Barbara Coastal Watershed 18060013 (southern highlighted watershed on map of CA on right).
The story doesn’t end there, however. Within each watershed are a variety of sources that comprise a water profile. Santa Barbara County as a whole has a diverse portfolio of water sources that vary by city. For brevity, consider the two cities most directly relevant to UCSB: Goleta (pop. 30,000, 2011) and Santa Barbara (pop. 89,000, 2011).
Goleta has a relatively simple water source portfolio (left). The city gets its water from two sources: Cachuma Lake (93%) and recycled water (7%). In 1953, the federal government funded construction of the Bradbury Dam on the Santa Ynez River. Cachuma Lake rose behind the dam to become Santa Barbara County’s largest reservoir. Tecolote Tunnel stretches about 6.4 miles through the Santa Ynez Mountains and diverts Lake Cachuma water for human use.
Recycled water is municipal wastewater reclaimed and treated to remove sediments and impurities so it can be reused. This water source is quickly gaining popularity—particularly in urban areas—in large part because it is a local, drought-resistant water supply that helps reduce reliance on groundwater and surface water. Education about the advantages of using recycled water is helping diminish stigmas that have historically limited its use. Goleta uses recycled water for landscaping at some parks, schools, and commercial properties.
Santa Barbara, on the other hand, has a mix of all five currently active county sources: groundwater (9%), Cachuma Lake (52%), local streams and reservoirs (28%), State Water Project (“SWP”, 6%), and recycled water (5%). Santa Barbara uses Cachuma Lake water and recycled water in much the same was as Goleta. However, with a population almost three times that of Goleta, Santa Barbara uses three additional sources of water. (note: Santa Barbara’s Charles Meyer Desalination Facility, built in 1991-1992 in response to severe drought, is now in long-term storage mode but can be reactivated if needed).
Groundwater is mostly self-explanatory—it is the water accumulated underground in spaces between clay, silt, sand, and gravel that forms aquifers. Groundwater is replenished at various rates (can range from a few days to centuries) as precipitation infiltrates the ground and accumulates above some impermeable layer. Although not the major source of water for Santa Barbara or Goleta, the county as a whole relies on it for almost 75% of total water use.
Local streams and reservoirs represent the area’s usable surface water, including manmade water stored behind reservoirs and diversion dams. Managing water supply can reduce flood and drought risks because stream flow is stored until needed. Reservoirs can also help replenish groundwater.
The State Water Project—conceptualized in 1919 and funded in 1960—diverts water from Northern California rivers through the California Bay-Delta and into the San Joaquin Valley. The SWP consists of over 700 miles of canals and pipelines, 34 storage facilities, and can store 5.8 million acre-feet of water. Diverted water is used for agriculture and pumped throughout Southern California for use by over 25 million Californians.
Whether a resident of Goleta, Santa Barbara, or other cities in Santa Barbara County, your water comes from one of these five described sources. Water is collected, stored, transported, treated, distributed, and recovered through a system of water infrastructure (see graphic above). Water connects us all and is the lifeblood for society. The next time we turn on the tap, remember there is a long, organized water system working to ensure not just the availability of water but its quality as well.
Where does your water come from?
Special thanks to RJ Zaworski for providing the wonderful graphics for today’s post.