Coastkeepers monitor the health of watersheds

RANCHO SANTA FE — One Saturday a month, volunteers head out with extension poles, filtration devices, thermometers and other data collection equipment with the intention of gathering as much information as possible on the health of San Diego County’s 11 watersheds.
San Diego Coastkeeper monitors nine of the 11 watersheds in the county.
Watersheds are essentially large drainage areas. All of the rain that falls on land collects into the rivers, creeks and lakes, making its way to the coast.
The San Dieguito Watershed drainage area is approximately 346-square-miles that begins in the west-central Santa Ysabel Mountains and runs through Rancho Santa Fe, eventually pouring out into the Pacific from Del Mar and Solana Beach. Each of the watersheds is monitored by trained volunteers.
George Liddle, a UCSD grad with a background in hydrogeology, has been a volunteer with the Coastkeepers for four years. He’s the captain of a three-person team that monitors the San Dieguito Watershed.
One Saturday a month, the team travels to three spots in the Rancho Santa Fe area to collect water samples and parameters around the site, including air and water temperatures, pH levels and noting any characteristics the surface of the water may show such as soapy bubbles, or growth of scum.
Each of the three sites was chosen using only a Thomas Brothers Guide and driving along streets looking for access points to the water. The sites tested included the San Dieguito River at Via de Santa Fe, the Lusardi Creek on Artesian Road and along Del Dios highway. Monitoring at one of the sites began in 2008, with the remaining sites being monitored in 2010.
The team also monitors any wildlife they might see. In one instance, Liddle noted the presence of dragonflys at one of the sites. “We note thoroughly everything we see,” he said. “You never know when a grad student might be studying dragonflys in the area.”
“We also note invasive plant species,” explained Rexanne Dayes, who’s volunteered for the past three years. “They affect insect life and birds will stop nesting in the area once an invasive species takes over”
“It’s a pretty radical change to the whole ecology,” Liddle said.
Common issues they see around the sites are trash pile-ups, but the trash isn’t primarily the problem, Liddle said. “The trash is pretty ubiquitous.”
What they see posing the most danger to the watershed is the presence of urban runoff. The testing they do is pretty basic, Liddle said, adding that the tests provide basically a “red light, green light,” type of result.
Travis Pritchard is lab coordinator for San Diego Coastkeeper.
The lab, which is based in Point Loma, receives all of the collection samples. Half of the testing is done on site for nutrient analysis with the second half undergoing analysis for dissolved metals at SDSU.
Once all of the data has been compiled it goes into a database and can be accessed by the general public and state and regional departments. The results coming in are just
now being used to be able to develop trends for the watershed, Pritchard said .
“The San Dieguito watershed is in good condition relative to the rest of San Diego’s watersheds,” Pritchard said. “It shows some problems typical of urbanization such as slightly elevated concentrations of some nutrients. This is typical of irrigation of agricultural land or over watering of lawns. Our sites are downstream of ag land and golf courses, so this probably explains the nutrient levels being slightly elevated.”
As for the slightly elevated levels, Pritachard added that they mostly don’t exceed the standards set in the San Diego region basin plan.
Pritchard did offer some caution regarding rapid urbanization and development of the open space still found in the San Dieguito watershed, adding that it will cause more water quality problems if low impact development practices aren’t used. He said that we would see the same problems as the Los Penasquitos watershed has seen due to the rapid growth of the Carmel Valley area.
According to the Project Clean Water organization, nearly half of the vacant land area is open to future development, most being zoned for residential usage. They add that they current population in the watershed, approximately 125,000 is projected to increase to over 210,000 residents by 2015.
San Diego Coastkeeper has 15 full-time biologists, activists and lawyers working to help protect and restore San Diego’s bays, beaches, rivers, creeks and lakes that feed into the ocean.
Full results of the testing may be found at
For more information on San Diego Coastkeeper and how to volunteer, visit


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