This is part 3 of a 5 part series of results from our water monitoring lab. If you haven’t read our watershed report, head over here and check it out. In this third part, we are going to take a look at the Pueblo watershed.
The Pueblo Watershed is San Diego County’s smallest, and most urbanized, watershed. This roughly 60 square mile watershed drains into San Diego Bay. The Pueblo Watershed runs through the heart of the City of San Diego and it’s boundaries overlap with portions of the Lemon Grove, La Mesa, and National City. The main creek running through the watershed is Chollas Creek, which has two main forks that run through the most densely populated part of the City. As a result, we have altered and lost much of it’s native habitat. Chollas Creek is straightened, channelized, or driven underground in various places.
Prior to development, the watershed supported a coastal scub habitat that was home to plant and animal species that were tolerant to the long dry seasons we have in San Diego. Much of this habitat has been developed away, transforming to heavy and light industry, parking lots ans strip malls, and houses with irrigated landscapes. Chollas creek itself was straightened, channelized, or driven underground in various places through pipes and culverts.
The extensive hydromodification of the creek has resulted in the loss of almost all of the natural habitat associated with the creek. In fact, the creek is so altered that nearby residents often don’t know there is a river flowing through their neighborhood. Now, only the tributary canyons offer some habitat for animals like the threatened Cactus Wren.
In general, our monitoring program found the creek has high levels of ammonia, phosphorus, fecal bacteria and trash. These pollutants are signatures of dense urban development. During the rainy season, these pollutants are carried from inland sources into the creek and out to the bay. The nutrients contribute to an excess of of algae growing in the creek and the trash contributes to our marine debris problem. For an good visual of how nutrients can affect water quality, check out this youtube video I made last year. Look at what a difference of a few drops of fertilizer can do water quality.
Fortunately there are a number of organizations trying to reverse this declining trend. Groundwork San Diego, Chollas Creek; The Jacobs Center for Neighborhood Innovation; and San Diego Canyonlands are working to restore the watershed’s natural hydrology and habitat. See what they are working on here . The Environmental Health Coalition is working hard on environmental justice issues in the area which will help abate some of the problems the area’s residents face by living so close to industrial and transportation centers.
Local municipalities are a part of the solution, as well.The city of San Diego has developed the Chollas Creek Enhancement Plan to guide it’s and other organizations efforts for repairing the creek. The local cities have also developed an urban runoff management plan for watersheds draining into San Diego Bay that sets up the programs for reducing the urban pollution.
There is a lot of work to be done in this watershed. It’s going to take many years of effort, but I have a vision of a vibrant creek supporting native habitat with parks and trails right in the middle of our city.
