These Ten Locations Featuring Urban Runoff Pollution Will Shock You

Every year, the first major rain after the dry summer season gives us an opportunity to see the complicated problem of urban runoff and its impacts to our water quality. Urban runoff is water that flows over thehard scape surfaces we fill our cities with and drains directly into our waters. Stormwater, irrigation, and other water carry pollutants such as trash, oil, grease, pesticides, metals, bacteria and viruses, and toxic chemicals.

And it washes into our rivers, bays, lakes and ocean – untreated. 

To unwind this major water quality issue in San Diego would require turning back the clock to a time before we developed the county and rethinking how we paved, connected and changed the natural landscape. Still, today, we can do things to capture or slow down runoff before it hits our water or to prevent pollutants in the first place. In thinking about our upcoming stormy season, we tapped the brains of our water quality sampling volunteers, who collect water samples from nine of our eleven watersheds, to produce this list of the top ten places to watch urban runoff. In no scientific way, we ordered it from the most basic visual to the most compelling. We target different pollutants, diverse geographic locations, a varierty of infrastructure impacts and human health and use impacts.

Take a look. What do you see?

10. 2306 S Coast Highway: Open channel dumping onto the beach

This popular North County surf spot features an open channel carrying urban runoff from the adjacent parking lot and highway straight onto the beach. This location highlights how stormwater washes trash and dissolved pollutants from our developed places onto our beaches.

9. 300 Forward Street in La Jolla/Bird Rock: Drain at the street’s end 

This is the most straightforward illustration of a storm drain labeled “drains to the ocean,” where you can see the drain, the end of the street and the polluted water and its entrance to the Pacific. It simply illustrates the complicated infrastructure our region built that assumed pushing all water into our bays and ocean was the smartest way to keep our homes and businesses dry. 

8. Tourmaline Surf Park: Channelized stormwater outlet meets popular surf spot

This Pacific Beach surf spot is world-renowned for its waves, thankfully not for its urban runoff pollution. Risking intestional illnesses of all sorts, surfers get barreled here when its raining, unaware that a paved stormwater channel leads direct to sandy beach and into the water. Polluted runoff in this channel dumps directly in the surf zone.

urban runoff effects

7. Coast Boulevard Park: Cement pipe at ocean’s edge

The Waterkeeper movement started decades ago because fisherman saw large industrial sites using massive pipes to discard pollution directly into the Hudson River. This location symbolizes San Diego’s version of that as a cement pipe carries polluted water from the storm drain straight to the ocean. With the Hudson’s pollution, fishermen could pinpoint a specific corporation responsible for dumping pollution into the water. In San Diego, it’s impossible to target one contributor to this issue because every person adds to the problem as rain water runs over our homes, yards, driveways, workplaces and more, until it carries accumalted toxins to this singular end point. In this spot, a large algae plume from the excess nutrients (commonly caused by fertilizer) grows along the rocks at the end of the drain. You can even see the algae mat in this photo to the right.

6. Cottonwood creek at Moonlight State Beach:Storm Drain opening

We’re particularly aware of this polluted runoff example because Moonlight Beach is a favorite among locals, families and surfers. It’s one of those rare beaches where a community member organizes regular cleanups to keep it trash free. Surfers flock here. Families play here. But, it’s also a prime location to see an open channel storm drain flow right to the sandy beach. 

5. San Dieguito River Park Stormwater Treatment lagoon: Treatment wetland in action

Is it too late to reverse the effects of polluted runoff? Absolutely not, especially when we get creative.

We chose this location because it showcases a stormwater pipe that drops large amounts of urban runoff from the nearby development. The folks at San Dieguito Lagoon built a treatment wetland to clean the water before it gets to the actual lagoon. Here, you’ll see the pipe dumping water into the first pond. This first pond always has stagnant algae pond water, even when it’s not raining. But, the good news in this solution-oriented example, is that you can see the treatment ponds prevent the gross water from reaching the lagoon. 

This illustrates what many people refer to as stormwater capture, and it also depicts the role that nature plays in helping humans handle polluted runoff.

In their natural state, our inland creeks slow polluted water and force it through nature’s filter–offering a true eco-cleanse that can remove a lot of urban runoff pollution from water before it reaches the ocean. Sandly, by channelizing many of San Diego County’s creeks, we dehabilitated nature’s role by replacing vegetation with paved concrete to quickly move water away from our developed areas into our bays and ocean. 

4. Tecolote Shores, Mission Beach: Creek emptying into man-made bay

Mission Bay is gross–in this part of the bay. Here Tecolote Creek drains into Mission Bay, a tourism hot spot that we engineered when we rerouted the mouth of the San Diego River. Due to the high bacteria counts in this creek, this section of Mission Bay is often closed for swimming, even when it’s not raining. It’s particularly polluted here year round because this far-back section of Mission Bay does not have much current to mix the polluted water into the open ocean.

3. Dog Beach, Ocean Beach: The mouth of our region’s largest river

The polluted runoff in this iconic location begins collecting bacteria and toxins from as far inland as Julian–the eastern edges of this watershed. The amount and the intensity of polluted runoff flowing through the mouth of this river demonstrate the gravity of our top water quality problem. Here, you’re also likely to see a secondary issue in urban runoff–marine debris.

2. 3001 Harbor Drive: Trash

This bridge overlooks the outlet for Chollas Creek, one of San Diego County’s most polluted creeks. Flowing through the most densely populated urban areas in the county, Chollas Creek is wrought with trash, oil, grease, pesticides, metals, bacteria and viruses and toxic chemicals. What makes this secure the #2 spot on our list of ten is that you can see a trash boom designed to capture trash flowing from upstream into the bay. Particularly with the popularity of photos on the Internet, many people have seen images from around the globe featuring humans in boats surrounded by massive amounts of trash in the water. It’s easy to dismiss that in San Diego because we do have strong trash and recycling systems in place. But, if you find yourself here at the end of Chollas Creek, you may see that marine debris issues are much closer to home than they appear. 

1. Dairy Mart Road: Binational polluted runoff

During the winter, the Tijuana River overruns the South Bay International Wastewater Treatment Plant in San Ysidro, California. It then runs through the Tijuana River Estuary, one of the largest remaining Southern California coastal wetland habitats. This area is as important stopover on the Pacific Flyway bird migratory route. Unfortunately, the river carries large amounts of raw sewage as well as trash and sediment straight through the estuary and onto the beaches near Imperial Beach. During the winter, the river flows close nearby beaches. This one location perfectly illustrates that urban runoff is not “one person’s problem” or even “one country’s problem.” It highlights trash management issues as well as chemical water quality issues. This location slots into #1 because of the severity of the polluted runoff, the amount of the water flowing in this spot and the complicated matter of finding solutions to polluted runoff that starts in the U.S., flows through Mexico and completes it journey back in America.

Did we miss a location that you think should earn a spot on our top ten list of places to experience and learn about polluted runoff issues? Please, share with us your ideas in the comments below.