Top

Heal the Bay Blog

Category: River Report Card

Celebrating Labor Day at the River or the Beach?

09.01.2017 |

Beach Report CardEventsL.A. RiverLos AngelesRiver Report CardWater Quality

Most people view Labor Day weekend as the last celebration of summer and a final opportunity to enjoy a relaxing water adventure either at the beach or the river. A last hurrah before settling into the fall season.  With that in mind, now is a good time to deliver a friendly reminder about water quality when heading to your favorite beach or stream.

First – let’s remember the basic safety tips.

These are some general rules to follow to lower your risk of getting sick when:

Going to the beach

  • Swim at least 100 yards from piers and flowing storm drains.
  • Because of poor circulation, water quality at enclosed beaches and harbors is often poorer than at open beaches.
  • Wait at least 3 days after a rainstorm before diving into the water (and wait at least 5 days before swimming at beaches near storm drains).

Going to the river

  • Do not drink the water.
  • After water contact, rinse off with soap and water.
  • Be aware of your swimming conditions (funny smells, homeless encampments, nearby drainages, posted signs) before entering the water.

Second – knowledge is power.

Heal the Bay has two great, if not awesome, sources of water quality information regardless of whether you are going to the beach or the river. In addition to practicing safe swimming, water enthusiasts should visit Heal the Bay’s Beach Report Card to get the latest information on all California beach conditions. (We publish the Beach Report Card on a weekly basis for the whole year, so can stay informed if you plan on swimming in the ocean beyond Labor Day Weekend.)

If you plan to visit a swimming hole in Los Angeles County this coming weekend, then see our River Report Card to see updated water quality information about these swimming holes.

Our motto has always been, and always will be: KNOW BEFORE YOU GO!

Have a great Labor Day Weekend!

Read More
Read Less


Heal the Bay Launches “The River Report Card”

07.27.2017 |

Los AngelesNewsRiver Report CardWater Quality

Today we begin publishing regular water quality grades for freshwater recreational zones across greater L.A. Staff scientist Dr. Katherine Pease explains why the work is so important, and some interesting people helping us do it.

Last summer, Heal the Bay released a landmark study of water quality that showed that bacterial pollution continues to plague the L.A. River on a chronic, long-term basis. Our scientific report demonstrated that increasingly popular recreation zones suffered from poor water quality, and posed health risks for the growing number of people fishing, swimming and kayaking its waters.

The findings were a cause for concern, but also served as an opportunity – given all the renewed interest about the L.A. River and a $1 billion revitalization plan for L.A.’s central water body.

Building on that study and our longtime work to protect public health by providing weekly water quality grades at California beaches, Heal the Bay this year committed to regular water quality monitoring in rivers throughout greater L.A.

Today, we take the wraps off our River Report Card, a new online tool that lets users check for harmful bacteria levels at nearly a dozen freshwater recreational zones, stretching from Malibu to Frogtown, from Encino to Atwater Village.

We began monitoring inland recreational areas in 2014, starting with swimming holes in the Santa Monica Mountains, and adding sites in the L.A. River in 2015. To make sure people could see whether these popular spots are clean and safe, we posted the test results online in a weekly blog.

With our expanded River Report Card, the public can use our online map to check out water-quality ratings (green, yellow, or red) at their favorite summer spot. We will update the grades twice a week, every Monday and Wednesday. The data come from bacteria testing by Heal the Bay staff, supplemented by testing by the City of Los Angeles and Council for Watershed Health as part of the Los Angeles River Watershed Monitoring Program (LARWMP).

Our report on the L.A. River water quality garnered quite a bit of attention last year, leading to improvements in public awareness about water quality issues in the River.

Among the positive changes:

  • The L.A. County Department of Public Health now has a webpage devoted to Fresh Water Swim Areas
  • Additional agencies now test at recreation sites in the L.A. River through the LARWMP program (Heal the Bay was previously the only group testing the Elysian Valley recreation sites)
  • L.A. City Sanitation has posted new signs along the L.A. River about water quality that Heal the Bay and L.A. County Department of Public Health recommended

In another positive development, Heal the Bay has recruited some local students to conduct this work.

Under an EPA grant, we’re partnering with Los Angeles Trade Technical College, a public community college in downtown Los Angeles. Five LATTC students have joined our field staff for the summer, to learn the science of water quality monitoring and the art of advocating for environmental protections – starting with the River in their own backyards.

The enthusiasm that these students bring to the River is contagious, and their varied backgrounds and experiences bring broad new perspectives to our watershed work. (You can read more about them here.) The training underscores Heal the Bay’s commitment to diversifying the ranks of environmental science and developing future leaders in our region.

We will highlight their voices and experiences over the rest of the summer through Heal the Bay’s blog and social media channels – check back often to hear what they have to say!

These students have been charged with an important task: identifying where pollution is entering the L.A. River. It’s an important question, not only for people along the banks of the River, but for ocean users as well. The vast majority of pollution at our beaches is carried there via rivermouths and stormdrain outfalls.

To pinpoint these nasty pollution sources, the LATTC students are biking along the L.A. River in the Elysian Valley to identify and sample flowing stormdrains.

Conducting this monitoring is fascinating – we get important data, and the opportunity to be up-close and personal with the River. Every week we see people using the river for recreational activities like fishing, wading and kayaking but also for basic human needs, such as bathing and washing clothes.

Areas with flowing water provide people and their dogs respite from the oppressive summer heat. They serve homeless encampments as a place to freshen up or bathe. They are also ground zero for the often-polluted urban runoff that harms people, habitat and wildlife in the rivers as well as downstream at the beach.

These are sobering observations, but there is good news too. More people are connecting with nature and discovering their own freshwater oases in urban L.A. And many inland locations have good water quality. Residents are working to protect these special places and keep them healthy and safe.

We encourage you to check back here often, explore your local water bodies, learn about water quality, and learn what you can do to improve the health of your watershed.

If you are thinking about getting out on the water, please check out our FAQ about recreation and water quality issues along the L.A. River.

Read More
Read Less


Freshwater Friday: Safe to Swim in Malibu Creek?

08.12.2016 |

Malibu / Pacific PalisadesRiver Report Card

For 2017 grades, please see our River Report Card.

Heal the Bay’s inaugural study of Los Angeles River microbial water quality that we published July 27, 2016 and last year’s study on swimming holes in the Santa Monica Mountains called for more readily available public water quality information. The public has a right to know about water quality conditions in these freshwater recreation areas so that they can make informed decisions on how to minimize the risk of getting sick.

We will be posting an update every Friday during the summer with water quality information from our weekly sampling of freshwater recreation sites in Los Angeles County.

Malibu Creek State Park – Number of Exceedances
Site Name9/29/169/21/169/15/169/7/168/31/168/24/168/17/168/10/168/3/16
Rock Pool0 out of 4

None of the four criteria exceed the threshold values this week at Rock Pool site in Malibu Creek. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml as was the geometric mean value for Enterococcus (below 30 MPN/100ml). Since June 15, 2016, we have documented exceedance rates (for single samples) of 20% for E. coli and 13% for Enterococcus at this site.
0 out of 4

None of the four criteria exceed the threshold values this week at Rock Pool site in Malibu Creek. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml as was the geometric mean value for Enterococcus (below 30 MPN/100ml). Since June 15, 2016, we have documented exceedance rates (for single samples) of 21% for E. coli and 14% for Enterococcus at this site.
0 out of 4

None of the four criteria exceed the threshold values this week at Rock Pool site in Malibu Creek. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml as was the geometric mean value for Enterococcus (below 30 MPN/100ml). Since June 15, 2016, we have documented exceedance rates (for single samples) of 23% for E. coli and 15% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at Rock Pool site in Malibu Creek. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since June 15, 2016, we have documented exceedance rates (for single samples) of 25% for E. coli and 17% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at Rock Pool site in Malibu Creek. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since June 15, 2016, we have documented exceedance rates (for single samples) of 27% for E. coli and 18% for Enterococcus at this site.
2 out of 4

Two of the four criteria exceed the threshold values this week at Rock Pool site in Malibu Creek. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. In contrast, both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since June 15, 2016, we have documented exceedance rates (for single samples) of 30% for E. coli and 20% for Enterococcus at this site.
1 out of 4

One of the four criteria exceeds the threshold values this week at Rock Pool site in Malibu Creek. For both E. coli and Enterococcus, the single sample values were under their respective thresholds. The geometric mean value for E. coli was under its threshold, while Enterococcus was over its threshold. Since June 15, 2016, we have documented exceedance rates (for single samples) of 33% for E. coli and 11% for Enterococcus at this site.
2 out of 4

Two of the four criteria exceed the threshold values this week at Rock Pool site in Malibu Creek. For both E. coli and Enterococcus, the single sample values were under their respective thresholds but the geometric mean values were over the thresholds. Since June 15, 2016, we have documented exceedance rates (for single samples) of 33% for E. coli and 12% for Enterococcus at this site.
3 out of 4

Three of the four criteria exceed the threshold values this week at Rock Pool site in Malibu Creek. For E. coli, the single sample and geometric mean values were over threshold values; the single sample Enterococcus value was under the threshold of 110 MPN/100ml but the geometric mean value was over the threshold value. Since June 15, 2016, we have documented exceedance rates (for single samples) of 43% for E. coli and 14% for Enterococcus at this site.
Las Virgenes Creek at the Bridge1 out of 4

Only one of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since June 15, 2016, we have documented exceedance rates (for single samples) of 27% for E. coli and 53% for Enterococcus at this site.
3 out of 4

Three of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was below the threshold of 235 MPN/100ml but the geometric mean value for E. coli was over the threshold of 126 MPN/100ml.The single sample Enterococcus value was over the threshold of 110 MPN/100ml and the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since June 15, 2016, we have documented exceedance rates (for single samples) of 29% for E. coli and 57% for Enterococcus at this site.
2 out of 4

Two of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was below the threshold of 235 MPN/100ml but the geometric mean value for E. coli was over the threshold of 126 MPN/100ml.The single sample Enterococcus value was below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since June 15, 2016, we have documented exceedance rates (for single samples) of 31% for E. coli and 54% for Enterococcus at this site.
2 out of 4

Two of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was below the threshold of 235 MPN/100ml but the geometric mean value for E. coli was over the threshold of 126 MPN/100ml.The single sample Enterococcus value was below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since June 15, 2016, we have documented exceedance rates (for single samples) of 33% for E. coli and 58% for Enterococcus at this site.
3 out of 4

Three of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample and geometric mean values for E. coli value were both over their respective thresholds of 235 MPN/100ml and 126 MPN/100ml. The single sample Enterococcus value was below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since June 15, 2016, we have documented exceedance rates (for single samples) of 36% for E. coli and 64% for Enterococcus at this site.
3 out of 4

Three of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was below the threshold of 235 MPN/100ml, while the geometric mean for E. coli was over 126 MPN/100ml. Both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since June 15, 2016, we have documented exceedance rates (for single samples) of 30% for E. coli and 70% for Enterococcus at this site.
4 out of 4

Four of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was above the threshold of 235 MPN/100ml, and the geometric mean for E. coli was over 126 MPN/100ml. Similarly, both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since June 15, 2016, we have documented exceedance rates (for single samples) of 33% for E. coli and 67% for Enterococcus at this site.
3 out of 4

Three of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was below the threshold of 235 MPN/100ml but the geometric mean for E. coli was over 126 MPN/100ml, and both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since June 15, 2016, we have documented exceedance rates (for single samples) of 25% for E. coli and 62% for Enterococcus at this site.
3 out of 4

Three of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was below the threshold of 235 MPN/100ml but the geometric mean for E. coli was over 126 MPN/100ml, and both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since June 15, 2016, we have documented exceedance rates (for single samples) of 29% for E. coli and 57% for Enterococcus at this site.
Los Angeles River – Number of Exceedances
Site Name9/27/169/20/169/13/169/6/168/30/168/23/16
Steelhead Park, Elysian Valley1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Steelhead Park site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 6% for E. coli and 61% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Steelhead Park site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 6% for E. coli and 65% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Steelhead Park site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 6% for E. coli and 69% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Steelhead Park site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 7% for E. coli and 73% for Enterococcus at this site.
2 out of 4

Two of the four criteria exceed the threshold values this week at the Steelhead Park site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. In contrast, both the single sample and geometric mean values for Enterococcus were over their respective thresholds (110 and 30 MPN/100ml). Since May 31, 2016, we have documented exceedance rates (for single samples) of 7% for E. coli and 79% for Enterococcus at this site.
2 out of 4

Two of the four criteria exceed the threshold values this week at the Steelhead Park site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. In contrast, both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since May 31, 2016, we have documented exceedance rates (for single samples) of 8% for E. coli and 77% for Enterococcus at this site.
Rattlesnake Park, Elysian Valley3 out of 4

Three of the four criteria exceed the threshold values this week at the Rattlesnake Park site for the Los Angeles River. The single sample value for E. coli was below the threshold of 235 MPN/100ml, but the geometric mean for E. coli was over the threshold of 126 MPN/100ml. Both the single sample and geometric mean values for Enterococcus were also over their respective thresholds (110 and 30 MPN/100ml). Since May 31, 2016, we have documented exceedance rates (for single samples) of 50% for E. coli and 100% for Enterococcus at this site.
4 out of 4

All four of the criteria exceed the threshold values this week at the Rattlesnake Park site for the Los Angeles River. The single sample and geometric mean values for E. coli value were above the thresholds of 235 and 126 MPN/100ml, respectively. Both the single sample and geometric mean values for Enterococcus were also over their respective thresholds (110 and 30 MPN/100ml). Since May 31, 2016, we have documented exceedance rates (for single samples) of 53% for E. coli and 100% for Enterococcus at this site.
4 out of 4

All four of the criteria exceed the threshold values this week at the Rattlesnake Park site for the Los Angeles River. The single sample and geometric mean values for E. coli value were above the thresholds of 235 and 126 MPN/100ml, respectively. Both the single sample and geometric mean values for Enterococcus were also over their respective thresholds (110 and 30 MPN/100ml). Since May 31, 2016, we have documented exceedance rates (for single samples) of 50% for E. coli and 100% for Enterococcus at this site.
3 out of 4

Three of the four criteria exceed the threshold values this week at the Rattlesnake Park site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, but the geometric mean for E. coli was over 126 MPN/100ml. Both the single sample and geometric mean values for Enterococcus were over their respective thresholds (110 and 30 MPN/100ml). Since May 31, 2016, we have documented exceedance rates (for single samples) of 47% for E. coli and 100% for Enterococcus at this site.
3 out of 4

Three of the four criteria exceed the threshold values this week at the Rattlesnake Park site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, but the geometric mean for E. coli was over 126 MPN/100ml. Both the single sample and geometric mean values for Enterococcus were over their respective thresholds (110 and 30 MPN/100ml). Since May 31, 2016, we have documented exceedance rates (for single samples) of 50% for E. coli and 100% for Enterococcus at this site.
4 out of 4

Four of the four criteria exceed the threshold values this week at the Rattlesnake Park site for the Los Angeles River. The single sample E. coli value was above the threshold of 235 MPN/100ml, and the geometric mean for E. coli was over 126 MPN/100ml. Similarly, both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since May 31, 2016, we have documented exceedance rates (for single samples) of 54% for E. coli and 100% for Enterococcus at this site.
Sepulveda Basin at Burbank Blvd.1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Sepulveda Basin site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 0% for E. coli and 6% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Sepulveda Basin site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 0% for E. coli and 6% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Sepulveda Basin site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 0% for E. coli and 6% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Sepulveda Basin site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 0% for E. coli and 7% for Enterococcus at this site.
1 out of 4

Only one of the four criteria exceeds the threshold values this week at the Sepulveda Basin site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. The single sample Enterococcus value was also below the threshold of 110 MPN/100ml but the geometric mean value for Enterococcus was over the threshold of 30 MPN/100ml. Since May 31, 2016, we have documented exceedance rates (for single samples) of 0% for E. coli and 7% for Enterococcus at this site.
2 out of 4

Two of the four criteria exceed the threshold values this week at the Sepulveda Basin site for the Los Angeles River. The single sample E. coli value was below the threshold of 235 MPN/100ml, and the geometric mean for E. coli was below 126 MPN/100ml. In contrast, both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since May 31, 2016, we have documented exceedance rates (for single samples) of 0% for E. coli and 8% for Enterococcus at this site.

We envision safe swimmable rivers and creeks throughout Los Angeles County. However, a number of recreational waterbodies are not regularly monitored or monitored at all. We know thousands of Angelenos use these aquatic resources.

As such, Heal the Bay would rather provide some information about the water quality they are immersing themselves into rather than no information. The idea is to prompt the user to ask questions about these waterbodies: What is the origin of the water? Can I get sick from it? What types of illnesses can I get? How do I get more information? Check out the answers to these questions and more in our FAQ and the joint statement on recreation in the L.A. River.

Malibu Creek State Park testing sites mapL.A. River testing sites map

Heal the Bay has been monitoring water quality in streams and rivers since 1998 through our Stream Team program. In 2014 we initiated a pilot study to monitor human use and water quality at freshwater swimming spots in the Santa Monica Mountains, focusing on bacterial pollution and public health implications. We are currently in our third summer of monitoring water quality in those swimming locations. Given Heal the Bay’s 25-year history of informing and educating beachgoers about beach water quality through our Beach Report Card, assessing the water quality of the Los Angeles River recreation zones was a natural next step. We are now in our second season of monitoring for the L.A. River recreation zones.

The A-to-F grading system of the Beach Report Card took years of work to develop and fine-tune. We are only in the very early stages of thinking about an analogous River Report Card. But we want to start by making basic water quality information available to the public in a timely manner.

We will be providing weekly information about levels of fecal indicator bacteria at five sites. We will report on whether the sample from the current week exceeded limits set by the Regional Water Quality Control Board and US EPA and what the microbial water quality has been over the summer sampling season thus far.

We will report on two types of fecal indicator bacteria, or FIB: E. coli and Enterococcus. FIB, while not harmful themselves, indicate the possible presence of pathogenic bacteria, which have been found to cause ear infections, skin rashes, respiratory illnesses and gastrointestinal illness. High levels of FIB are particularly concerning in areas where people come in contact with water through activities like swimming, fishing, and kayaking.

Excuse us for getting technical in this next section, but we just want to be clear about what we are measuring and what constitutes an exceedance.

We compare bacteria levels measured at each site to water quality objectives from the Total Maximum Daily Loads (TMDL) for Bacteria in the Malibu Creek Watershed and the Los Angeles River Watershed as well as EPA’s 2012 Recreational Water Quality Criteria (RWQC)

The freshwater regulatory limit for E. coli is set in the TMDL at 235 MPN/100ml for a single sample and 126 MPN/100ml for the geometric mean. (A geometric mean is a type of average that results in a number that is not as heavily affected by very high or very low values).

We calculate geometric means from all samples over the last 30-day period (usually four or five samples). For Enterococcus, we used EPA’s statistical threshold value for an illness rate of 32/1,000 (the more protective rate), which is 110 MPN/100ml for a single sample and 30 MPN/100ml for the geometric mean in a fresh waterbody designated for recreation.

For each site, we will report on the number of criteria that exceeded four standards. A site can have 0-4 out of four exceedances. A sample exceeds if:

  • E. coli single sample > 235 MPN/100ml
  • E. coli geometric mean > 126 MPN/100ml
  • Enterococcus single sample is > 110 MPN/100ml
  • Enterococcus geometric mean is > 30 MPN/100ml

So, what does that all mean?

The greater the number and magnitude of exceedances at a site, the worse the water quality is, indicating a potentially increased risk of getting sick.

Deciding what to do with this information depends on the risk level you are comfortable with. Single sample values give you an indication of the most recent water quality, while geometric mean values give you an indication of the ambient water quality over the last 30 days.

However, it is important to note that the single sample gives information for the day on which the sample was taken and conditions can change throughout the week until the next sample is taken.

The thresholds that the US EPA and the RWQCB have put forth are based on epidemiological studies and risk. An increased risk of illness is not a guarantee that you will get sick. Certain activities are more risky when water quality is poor; for instance, swimming and submerging your head is more risky than wading; swimming is more risky than kayaking; kayaking is likely more risky than hiking (at least with regards to picking up a waterborne illness), and so on, with the risk dependent on how likely you are to ingest or contact water.

We recommend following these best practices to stay safe and healthy.

  • Swimming: In waters known to exceed bacterial limits, swimming is not recommended, particularly submerging one’s head. Elevated bacteria levels can occur at any time. Swimmers should use caution when entering the water by checking the latest water quality results, avoiding contact immediately after a rainfall, if they are immunocompromised, or if they have an open wound. If there is any water contact, then rise off with soap and water afterward.
  • Kayaking and Fishing: In waters that are known to exceed bacterial limits, people should limit water contact, especially avoiding hand-to-face water contact. Users should not enter the water with an open wound, if immunocompromised, or after a rainfall. If there is any water contact, then rinse off with soap and water afterward.
Read More
Read Less


Freshwater Friday: Safe to Swim in Malibu Creek?

08.05.2016 |

Malibu / Pacific PalisadesRiver Report Card

Aug, 5, 2016 — Staff scientist Katherine Pease launches our Freshwater Friday blog post, providing weekly updates on the latest bacterial exceedances at popular recreational zones

Heal the Bay’s inaugural study of Los Angeles River microbial water quality that we published last week and last year’s study on swimming holes in the Santa Monica Mountains called for more readily available public water quality information. The public has a right to know about water quality conditions in these freshwater recreation areas so that they can make informed decisions on how to minimize the risk of getting sick.

So beginning today with our Santa Monica Mountains sites, we will be posting a blog post every Friday during the summer with water quality information from our weekly sampling of freshwater recreation sites in Los Angeles County. (You can see this week’s findings at the bottom of this page, but first we want to explain our intent and methodology.)

We envision safe swimmable rivers and creeks throughout Los Angeles County. However, a number of recreational waterbodies are not regularly monitored or monitored at all. We know thousands of Angelenos use these aquatic resources.

As such, Heal the Bay would rather provide some information about the water quality they are immersing themselves into rather than no information. The idea is to prompt the user to ask questions about these waterbodies: What is the origin of the water? Can I get sick from it? What types of illnesses can I get? How do I get more information? We will be posting a Frequently Asked Questions document next week to help answer some of these questions.

Heal the Bay has been monitoring water quality in streams and rivers since 1998 through our Stream Team program. In 2014 we initiated a pilot study to monitor human use and water quality at freshwater swimming spots in the Santa Monica Mountains, focusing on bacterial pollution and public health implications.

The A-to-F grading system of the Beach Report Card took years of work to develop and fine-tune. We are only in the very early stages of thinking about an analogous River Report Card. But we want to start by making basic water quality information available to the public in a timely manner.

We will be providing weekly information about levels of fecal indicator bacteria at five sites. We will report on whether the sample from the current week exceeded limits set by the Regional Water Quality Control Board and US EPA and what the microbial water quality has been over the summer sampling season thus far.

We will report on two types of fecal indicator bacteria, or FIB: E. coli and Enterococcus. FIB, while not harmful themselves, indicate the possible presence of pathogenic bacteria, which have been found to cause ear infections, skin rashes, respiratory illnesses and gastrointestinal illness. High levels of FIB are particularly concerning in areas where people come in contact with water through activities like swimming, fishing, and kayaking.

Excuse us for getting technical in this next section, but we just want to be clear about what we are measuring and what constitutes an exceedance.

We compare bacteria levels measured at each site to water quality objectives from the Total Maximum Daily Loads (TMDL) for Bacteria in the Malibu Creek Watershed and EPA’s 2012 Recreational Water Quality Criteria (RWQC)

The freshwater regulatory limit for E. coli is set in the TMDL at 235 MPN/100ml for a single sample and 126 MPN/100ml for the geometric mean. (A geometric mean is a type of average that results in a number that is not as heavily affected by very high or very low values).

We calculate geometric means from all samples over the last 30-day period (usually four or five samples). For Enterococcus, we used EPA’s statistical threshold value (for an illness rate of 32/1,000 (the more protective rate), which is 110 MPN/100ml for a single sample and 30 MPN/100ml for the geometric mean in a fresh waterbody designated for recreation.

For each site, we will report on the number of criteria that exceeded four standards. A site can have 0-4 out of four exceedances. A sample exceeds if:

E. coli single sample > 235 MPN/100ml 

E. coli geometric mean > 126 MPN/100ml

Enterococcus single sample is > 110 MPN/100ml

Enterococcus geometric mean is > 30 MPN/100ml

So, what does that all mean?

The greater the number and magnitude of exceedances at a site, the worse the water quality is, indicating a potentially increased risk of getting sick.

Deciding what to do with this information depends on the risk level you are comfortable with. Single sample values give you an indication of the most recent water quality, while geometric mean values give you an indication of the ambient water quality over the last 30 days.

However, it is important to note that the single sample gives information for the day on which the sample was taken and conditions can change throughout the week until the next sample is taken.

The thresholds that the US EPA and the RWQCB have put forth are based on epidemiological studies and risk. An increased risk of illness is not a guarantee that you will get sick. Certain activities are more risky when water quality is poor; for instance, swimming and submerging your head is more risky than wading; swimming is more risky than kayaking; kayaking is likely more risky than hiking (at least with regards to picking up a waterborne illness), and so on, with the risk dependent on how likely you are to ingest or contact water.

We recommend following these best practices to stay safe and healthy.

  • Swimming: In waters known to exceed bacterial limits, swimming is not recommended, particularly submerging one’s head. Elevated bacteria levels can occur at any time. Swimmers should use caution when entering the water by checking the latest water quality results, avoiding contact immediately after a rainfall, if they are immunocompromised, or if they have an open wound. If there is any water contact, then rise off with soap and water afterward.
  • Kayaking and Fishing: In waters that are known to exceed bacterial limits, people should limit water contact, especially avoiding hand-to-face water contact. Users should not enter the water with an open wound, if immunocompromised, or after a rainfall. If there is any water contact, then rinse off with soap and water afterward.

Malibu Creek State Park

for the week ending August 3, 2016

1. Rock Pool: Three exceedances

Three of the four criteria exceed the threshold values this week at Rock Pool site in Malibu Creek. For E. coli, the single sample and geometric mean values were over threshold values; the single sample Enterococcus value was under the threshold of 110 MPN/100ml but the geometric mean value was over the threshold value. Since June 15, 2016, we have documented exceedance rates (for single samples) of 43% for E. coli and 14% for Enterococcus at this site.

2. Las Virgenes Creek at the bridge: Three exceedances

Three of the four criteria exceed the threshold values this week at Las Virgenes Creek at the bridge. The single sample E. coli value was below the threshold of 235 MPN/100ml but the geometric mean for E. coli was over 126 MPN/100ml, and both the single sample and geometric mean values for Enterococcus were over their respective thresholds. Since June 15, 2016, we have documented exceedance rates (for single samples) of 29% for E. coli and 57% for Enterococcus at this site.

Read More
Read Less