State of the San Gabriels Rivers Watershed Symposium
From Wendy Wert, LA County Sanitation Districts
On July 20, 2011 the Council for Watershed Health (Council) hosted a State of the San Gabriel River Watershed Symposium, in Whittier, CA. This Symposium presented results from a 5-year State of the Watershed Report, which represents the culmination of a successful, cooperative watershed scale monitoring program. The Symposium opened with remarks from Executive Director, Nancy Steele who set the stage for this collaborative program. Nancy stated that the Council and its partners envision a healthy, sustainable San Gabriel River Watershed that meets the water quality, water supply, recreational and habitat needs of its human and biological communities. Nancy thanked the participants who contributed staff time, laboratory analyses, and funding in a collaborative effort that involved representatives of regulated, regulatory, environmental, and research organizations, which included the: Sanitation Districts of Los Angeles County (Sanitation Districts), City of Downey, Los Angeles County Flood Control District, Los Angeles Department of Water and Power, Council for Watershed Health, Los Angeles Regional Water Quality Control Board, Orange County Stormwater Program, Santa Ana Regional Water Quality Control Board, Southern California Coastal Water Research Project, and the U.S. EPA. A majority of the funding was provided by the Sanitation Districts.
Dr. Brock Bernstein related that in 2004, these key stakeholders formed the San Gabriel River Regional Monitoring Program (SGRRMP) to establish a monitoring framework that could go back to the baselines presented in the Clean Water Act and answer the following Questions:
1. What is the condition of the streams in the watershed?
2. Are conditions at the areas of unique interest getting better or worse?
3. Are receiving waters near dischargers meeting water quality objectives?
4. Is it safe to swim?
5. Are locally caught fish safe to eat?
Speaker Sharon Green continued the discussion with an overview of the San Gabriel Watershed, which encompasses over 689 square miles, contains over 1,236 miles of streams that traverse a magnitude of environments on their journey from the San Gabriel Mountains to the Pacific Ocean. The San Gabriel River Watershed supports a population of more than 2.3 million people. Protection and management to ensure the sustainability of this resource requires an understanding of the watershed’s overall health and the major stressors that affect its condition.
Dr. Kristy Morris explained that, since 2005, SGRRMP has performed rigorous scientific monitoring at targeted and randomly selected sites distributed throughout the watershed during dry weather (May through July). The program capture data from the mountainous upper watershed, the highly urbanized lower watershed and the main channel. The SGRRMP has successful shown that an integrated watershed monitoring program can provide context to these essential management questions, while improving monitoring efficiencies.
Speaker Scott Johnson explored question 1, by explaining that the stream condition was assessed through the measurement of multiple indicators, which include biological communities, chemicals of concern, toxicity, and physical habitat. These were conducted at 69 randomly selected sites, the biological condition of streams was assessed using the Southern California Index of Biological Integrity (IBI) for aquatic insects. Biological communities in the San Gabriel Mountains had the highest IBI scores indicated that their populations were relatively undisturbed. In contrast, the biological communities in the highly urbanized lower watershed and main channel were much more disturbed as indicated by lower IBI scores. Not surprisingly, analysis of physical habitat data such as the California Rapid Assessment Method (CRAM) indicated that areas with the best, least disturbed physical habitat supported the healthiest aquatic insect communities while locations with the worst physical habitat scores exhibited the lowest biological community condition. Unexpectedly, water toxicity was most frequently observed in the high biologically performing upper watershed locations and was never observed in the highly urbanized main stem.
Dr. Eric Stein continued the discussion with a review of the water chemistry results of the study. Aquatic chemistry indicated that attainment of Basin Plan objectives was typically achieved throughout the watershed. Although below protective thresholds, nutrients and heavy metals were higher in the main stem compared to the upper watershed. Eric encouraged symposium participants to continue to collect quality data since it takes 15 to 20 years to see trends and capture anomalies. An example demonstrated that the east fork of the San Gabriel River received 50% of its sediment load during three high rainfall events. Eric summed it up with an Einstein quote “It’s not that I’m so smart it’s just that I stay with problems longer.”
Speaker Karen Larsen explored question 2, by describing a few regional results from the statewide Surface Water Ambient Monitoring Program (SWAMP). Assessing the baseline condition of sites and following them over time can inform managers when restorative or protective measures need to be taken. Over a five-year period, the SGRRMP studies three key watershed habitats to determine how chemistry, toxicity, biological communities, and physical habitat conditions might be improving or declining over time. Karen explained that no clear trends emerged over the five years at the eight confluence points in the upper and lower watershed. The San Gabriel River estuary is a highly modified channel interfacing between the freshwater upper watershed and the ocean. Sediment chemistry, biological, and toxicity data were assess at two sampling locations using tools specific to the State’s sediment quality objectives (SQOs). Application of the SQO at these two locations indicated “likely impacted” considering the three lines of evidence. The SGRRMP employed CRAM to determine the overall wetland conditions, including geomorphology, vegetation, riparian zone, and floodplain of four, high value wetland habitats. Conditions were stable at these sites of the five-year period, however, there were some locations that resulted in moderate to poor CRAM scores. So what does this mean from the State Water Resources Control Board’s perspective? Karen explained that methods can be inconsistent in identifying impairments. Karen presented “hypothetical” data and suggested that it may be appropriate to categorize streams in three ways (1) high range performing where no degradation would be expected (2) middle range performance where adjustments could be made to improve conditions (3) lower range performing which may be the correct designation for some highly urbanized concrete lined segments. It is postulated that a categorical approach could support resource optimization.
Speaker Phil Markle explored question 3, by explaining that stewards of receiving waters need to know the potential impacts from known point source discharges in the watershed. This initial five-year study focused on the impact of effluent from five publicly owned treatment facilities (POTWs) discharging to the San Gabriel River. Nearly every chemical constituent, including nutrients, metals and organics that was assessed against a water quality standard was within the Basin Plan thresholds regarded as safe for human and aquatic life. E. coli concentrations were lower below the effluent discharges compared to upstream, where concentrations were routinely greater than California standards. This is presumable the result of dilution of the upstream water with disinfected, E. Coli-free effluents.
Phil also detailed the few exceedances that were observed during the 5-year study. There were a few hits for diazinon, a pesticide that EPA has banned that was observed in a few samples. Early in the study there were a few ammonia exceedances, however, in late 2003 the Sanitation Districts concluded implementation of a nitrification/denitrification (NDN) at all five POTWs and as a result receiving water ammonia concentrations have been reduced. Phil also observed that toxicity tests are rigorous since they are based on biology. Unlike chemical tests, which are only capable of measuring a specific water quality constituent, toxicity tests measure the cumulative biological effects of all substances present in the source water. Phil commented that the main stem exhibited no toxicity whereas the upper showed a 35% occurrence of toxicity and the lower showed a 20% occurrence of toxicity. Therefore, toxicity does not appear to be a water quality issue. Phil also postulated that the apparent habitat impairment could be an artifact of the different types of insect cultures that naturally occur in mountain streams (high velocity flow) versus alluvial river zones (lower velocity flow) so that comparing these may not be the most effective assessment tool.
Speaker Gary Hildebrand then broadened the discussion to examine the magnitude of diversity that the San Gabriel River Watershed encompasses. The watershed includes 48 cities and three counties. Precipitation throughout the watershed is variable from 27 inches in the mountainous areas to 12 inches observed in the coastal areas in an average year. Gary provided the extreme occurrence of 0.65 inches recorded in one minute at a gauging station in the mountains. Gary also provided a brief history of the basin as it relates to adjudicated water rights, which began with the 1887 San Gabriel River Water Committee also known as the “Group of 9.” The Los Angeles County Flood Control District was formed in 1915 to attenuate downstream inundation. The Flood Control District operates thee dams and reservoirs in the San Gabriel River Watershed. These were cited specifically to capture stormwater for infiltration purposes. The Flood Control District currently captures and infiltrates 90% of the stormwater generated from rainfall events in the upper basin. The Flood Control District partners with the US Army Corps of Engineers to manage the Santa Fe Dam. The Santa Fe Dam was built by the Corps in 1939. During average rainfall conditions the Flood Control District infiltrates 250,000 acre feet per year but has infiltrated as much as 750,000 acre feet per year during the El Nino 2004-2005 water year.
Keynote Speaker the Honorable Mary Ann Lutz then presented a challenging view of the path forward for the stewards of the San Gabriel River Watershed. There are apparent contradictions in watershed goals and resource allocations. For example, as the Mayor of Monrovia (one of the 48 cities within the San Gabriel River Watershed) there concerns related to the Municipal Separate Storm Sewer Systems (MS4s) permits. The City estimates that 10% of the General Fund will be required to comply with the associated bacteria Total Maximum Daily Loads (TMDLs). To put this in perspective, these dollars equal the funds presently allocated for the City’s Fire Department. And there is more bleak news, the unemployment rate is 9%, home values are declining, the state is in a budgetary crisis, the federal deficit is 14.3 trillion, local sales tax revenues are declining, and grant funding is virtually non-existent. Historically, new regulations have promulgated litigation in this region. Litigation does not result in improvements in water quality, but rather further depletes already taxed resources. The reality is that stormwater runoff has water quality impacts to surface waters within the San Gabriel River Watershed. The path forward then is through an integrated approach to water quality that establishes a collaborative cooperative culture, which supports the development of effective science based regulations. To make this work, all vested parties must strive to reach common ground. Mary Ann challenged cities and counties to acknowledge that environmental quality is one of the many vital services that they are commissioned to provide, community advocates to acknowledge that effective strategies require resource allocations, and the water board to acknowledge that it must take on a leadership role. In conclusion, Mary Ann asked all stakeholders to proceed with our interactions through the recognition of the correlation between the water cycle and the life cycle.
Speakers Gerry Greene, Bernard Franklin, Jim Hughes, and Lisa Northrop explored question 4, by discussing the human health implications associated with swimming in the streams and lakes in the watershed. The SGRRMP initiated a bacteria monitoring program in the summer of 2007 to specifically assess swimming safety. Eight popular swimming locations in the upper watershed were monitored for E. coli during the water spring and summer months from May through September when the density of swimmers is greatest. E. coli levels during 2007-2009 were typically below California standards indicating that it is safe to swim. Occasionally these standards were exceeded on weekends or holidays when recreational use was high. The EPA is currently reviewing alternative technologies and methodologies for more rapid detection and quantification of pathogenic bacteria. These methods could also assist in identifying the source of contamination.
Speakers Michael Lyons, Shannon Grund, and Scott Johnson explored question 5, by explaining that in order to protect people from the potential risk of eating contaminated fish, managers need data on the levels of unsafe contaminants in fish tissues. Prior to 2006, little was known about the safety of consuming recreationally caught fish from the watershed’s estuary, rivers and lakes. Four contaminants (mercury, selenium, total DDTs and total PCBs) were analyzed and then compared to State standards. Three fish species (tilapia, red ear sunfish, and bluegill) did not exceed consumption thresholds during the four year period. Largemouth bass and common carp caught in Puddingstone Lake and the Santa Fe Dam recreation Area Lake had elevated mercury concentrations at levels that warrant limiting consumption by humans. Common carp, largemouth bass and striped mullet captured in the upper estuary contained PCB concentrations suggesting that their consumption be limited to one meal per week.