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Los Angeles River Watershed UCLA Recent Work Title LA Sustainable Water Project: Los Angeles River Watershed Permalink https://escholarship.org/uc/item/42m433ps Authors Mika, Katie Gallo, Elizabeth Read, Laura et al. Publication Date 2017-09-19 License https://creativecommons.org/licenses/by-nc/4.0/ 4.0 eScholarship.org Powered by the California Digital Library University of California LA SUSTAINABLE WATER PROJECT: LOS ANGELES RIVER WATERSHED This report is a product of the UCLA Institute of the Environment and Sustainability, UCLA Sus- tainable LA Grand Challenge, and Colorado School of Mines. AUTHORS Katie Mika, Elizabeth Gallo, Laura Read, Ryan September 2017 Edgley, Kim Truong, Terri Hogue, Stephanie Pincetl, Mark Gold ACKNOWLEDGEMENTS UCLA Grand Challenges, Sustainable LA This research was supported by the City of Los 2248 Murphy Hall Angeles Bureau of Sanitation (LASAN). Many Los Angeles, CA 90005-1405 thanks to LASAN for providing ideas and direc- tion, facilitating meetings and data requests, as well as sharing the many previous and current re- UCLA Institute of the Environment and search efforts that provided us with invaluable in- Sustainability formation on which to build. Further, LASAN La Kretz Hall, Suite 300 and LADWP provided data and edits that helped Box 951496 to deepen and improve this report. Any findings, Los Angeles, CA 90095-1496 opinions, or conclusions are those of the authors and do not necessarily reflect those of LASAN. Colorado School of Mines 1500 Illinois Street Golden, CO 80401 We would like to acknowledge the many organiza- tions which facilitated this research through providing data, conversations, reviews, and in- sights into the integrated water management world in the Los Angeles region: LADWP, LAC- DPW, LARWQCB, LACFCD, WRD, WBMWD, MWD, SCCWRP, the Mayor’s Office of Sustaina- bility, and many others. 1 | LA Sustainable Water Project: Los Angeles River Watershed Contents Executive Summary .................................................................................................................. 5 Background ............................................................................................................................. 11 I. Introduction .................................................................................................................... 12 A. Los Angeles River Watershed Study Area ................................................................. 12 B. Hydrology of the Los Angeles River Watershed ........................................................ 13 C. Donald C. Tillman, LA Glendale, & Burbank Water Reclamation Plants ................. 13 D. Upper LAR Area groundwater basins ........................................................................ 15 II. Stormwater Quality Modeling ........................................................................................ 17 A. Introduction ................................................................................................................ 17 B. Policy Background ..................................................................................................... 17 a. Upper LAR MS4 Programs .................................................................................... 17 b. Total Maximum Daily Loads .................................................................................. 19 C. Stormwater Modeling for Metal TMDLs ................................................................... 21 a. Metals TMDL Background ..................................................................................... 21 b. Site-Specific Objectives for Copper and Lead ........................................................ 21 c. Modeling Selection and Comparison ...................................................................... 24 d. SUSTAIN Model Setup, Calibration, Validation ................................................... 24 e. BMP Technologies in SUSTAIN ............................................................................ 32 f. Cost Background ..................................................................................................... 34 g. BMP Optimization .................................................................................................. 35 h. Modeling Results .................................................................................................... 36 D. Policy Analysis ........................................................................................................... 42 a. Dry Weather Load-Based TMDL ........................................................................... 42 b. Nutrient TMDL ....................................................................................................... 48 c. LID Redevelopment Rate Impacts .......................................................................... 50 d. Stream Buffer Ordinances ....................................................................................... 53 e. Discussion ............................................................................................................... 56 III. Historical Flow Analysis in Mainstem and Selected Tributaries ............................... 59 A. Introduction ................................................................................................................ 59 B. Flows in LAR and selected tributaries ....................................................................... 61 a. Runoff Ratio............................................................................................................ 61 2 | UCLA IoES, UCLA GC, CSM September 2017 b. Historic Flow Percentiles ........................................................................................ 63 c. Historic Seasonal Flows .......................................................................................... 64 d. Low Flow 7Q Analysis ........................................................................................... 66 e. Impacts of BMPs on Streamflow ............................................................................ 69 f. Impacts of WRPs on Streamflow ............................................................................ 74 g. Historical Flow Discussion ..................................................................................... 76 C. Establishing minimum flows to protect and enhance beneficial uses on the LAR .... 78 a. LAR Background .................................................................................................... 78 b. Recent Work ........................................................................................................... 81 c. Complexities around Removing River Flows ......................................................... 84 d. Assessing Minimum Flows ..................................................................................... 85 IV. Groundwater ............................................................................................................... 88 A. Introduction ................................................................................................................ 88 B. Upper LAR Area Groundwater Basins ....................................................................... 91 a. San Fernando Groundwater Basin .......................................................................... 91 b. Sylmar Groundwater Basin ..................................................................................... 95 c. Verdugo Groundwater Basin .................................................................................. 96 d. Eagle Rock Groundwater Basin .............................................................................. 97 e. Groundwater Storage .............................................................................................. 97 f. Salt and Nutrient Management Plan ....................................................................... 99 C. Remediation Efforts .................................................................................................. 100 a. Current Projects, Plans, and Partnerships ............................................................. 100 b. Future Remediation Efforts................................................................................... 106 D. Increasing Stormwater Recharge .............................................................................. 108 a. Current and Planned Projects ................................................................................ 108 b. Increasing Stormwater Capture ............................................................................. 112 E. On Groundwater Recharge and Extraction ............................................................... 117 a. Remediation .......................................................................................................... 117 b. Recharge ............................................................................................................... 118 c. Explore Additional ULARA Opportunities .......................................................... 119 V. Wastewater and Recycled Water .................................................................................. 122 A. Introduction .............................................................................................................. 122 B. Water Reclamation Plants Background .................................................................... 122 C. Groundwater Recharge ............................................................................................
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