San Gabriel River Regional Monitoring Program
Key Program Documents

Question 1: What is the condition of streams in the watershed?

Parameters measured to assess the condition of streams in the watershed includes water chemistry, biological condition and physical habitat condition. This multiple lines of evidence approach provides stream condition information on a watershed-wide basis. By collecting and analyzing data from locations throughout the watershed over time, we have begun to gain a better understanding of the condition of streams and the key stressors to this condition. Sampling for this program has been conducted annually in the summer months since 2005 to present, with over 100 sites sampled from locations throughout the watershed. To learn more about this program go to any of the Annual Assessment Reports under Publications and Presentations, Chapter 1, on this website.

Question 2: Are conditions at unique sites changing over time?

This question focuses on how conditions are changing over time at sites of unique interest to watershed managers. From 2006 to 2016 eight San Gabriel River confluence sites were sampled for biotic and habitat condition each year. Having determined that trends at these sites were either highly variable or without specific increasing or decreasing trends over ten years, the Stakeholders redesigned the program in 2017. The Stakeholder group used the following criteria to select sites: 1) the site had biotic condition scores that were either under or over performing based on landscape context; 2) sites were linked to a management program (e.g. TMDL); or 3) the site was effected by natural phenomena (e.g. fires or floods). Based on these criteria, seven new target sites were identified and will be sampled annually for at least five years. To learn more about this new SGRRMP trend site program go to the 2018 and later Annual Assessments Reports under Publications and Presentations, Chapter 2, on this website.

Question 3: Are receiving waters downstream of discharges meeting regulatory requirements?

This question was answered using routine NPDES monitoring data collected downstream of five Los Angeles County Sanitation Districts (LACSD) waste treatment facilities (POTWs). This question assesses the potential impacts from these point source discharges into the San Gabriel River and its tributaries. To accomplish this, NPDES receiving water data was evaluated against regulatory thresholds for E. coli, ammonia, dissolved metals, and trihalomethanes. To learn more about this program go to any of the Annual Assessment Reports under Publications and Presentations, Chapter 3, on this website.

Question 4: Is it safe to swim?

The parameter measured to assess swimming safety includes a fecal indicator bacteria (FIB) called E. coli. The presence of E. coli in a water body indicates fecal contamination may have occurred, especially as the concentrations increase above State of California recreational standards (AB411).
The SGRRMP has measured E. coli at up to nine recreational swim sites located in the upper watershed, five times per month, from May to September each year since 2008.

Question 5: Is it safe to eat fish?

Parameters measured to assess fish consumption safety include tissue concentrations of mercury, arsenic, selenium, DDTs, PCBs dissected from sportfish located at popular swim sites. The concentrations of these constituents are compared to State of California consumption thresholds to determine if they are safe to eat. Since 2008 fish have been collected from 6 fishing sites and analyses have been performed on 13 species.