Santa Ana River Wasteload Allocation Model Update BASIN MONITORING - PowerPoint PPT Presentation

Santa Ana River Wasteload Allocation Model Update BASIN MONITORING PROGRAM TASK FORCE August 16, 2017

Model Development Existing WLAM (R4) WLAM Update Expanded Area • 564 subareas were delineated. • Each subarea consists of • Stream segment, • Pervious land area, and • Impervious land area. • They were delineated based on: • Topography • Drainage Patterns • Types of stream channels, and • Location of gaging stations and recharge basins 2

Schematic Diagram of HSPF TDS Simulation PERVIOUS LAND AREA TDS from PQUAL Upstream Reaches Storage of TDS on Surface for Direct Wash-off by Overland Flow STREAM SEGMENT (REACH) Total Storage of TDS Associated with Outflow CONS Interflow of TDS Storage of TDS Associated with Active Groundwater TDS of TDS Outflow (VOL*CON) from IMPERVIOUS LAND AREA Storage Reach IQUAL Total Wash-off Storage of TDS on Surface for Outflow Direct Wash-off by Overland Flow of TDS TDS from Precipitation 3

Schematic Diagram of HSPF TIN Simulation PERVIOUS LAND AREA TIN from PQUAL Upstream Reaches Storage of TIN on Surface for Direct Wash-off by Overland Flow STREAM SEGMENT (REACH) Total Storage of TIN Associated with Outflow RQUAL Interflow of TIN OXRX Subroutine Simulate primary Storage of TIN Associated with dissolved oxygen Active Groundwater and biochemical TIN of oxygen demand Outflow balances from IMPERVIOUS LAND AREA Reach NUTRX Subroutine IQUAL Determine TIN balances Total Wash-off Storage of TIN on Surface for Outflow Direct Wash-off by Overland Flow of TIN TIN from Precipitation 4

Daily TDS at Santa Ana River at MWD Crossing R4 – WY 1995 to 2006 1,000 Model-Calculated Daily TDS, 900 Mean Residual = 16.4 mg/L Observed 800 700 600 mg/L 500 400 300 200 Model-Calculated 100 0 Oct-94 Oct-96 Oct-98 Oct-00 Oct-02 Oct-04 HSPF – WY 2007 to 2016 1,000 Model-Calculated Daily TDS, 900 Mean Residual = -0.9 mg/L 800 700 600 mg/L 500 400 300 200 100 0 Oct-06 Oct-08 Oct-10 Oct-12 Oct-14 5

Daily TDS at Santa Ana River below Prado R4 – WY 1995 to 2006 1,000 Model-Calculated Daily TDS, 900 Mean Residual = 20.7 mg/L Observed 800 700 600 mg/L 500 400 300 200 100 Model-Calculated 0 Oct-94 Oct-96 Oct-98 Oct-00 Oct-02 Oct-04 HSPF – WY 2007 to 2016 1,000 900 Model-Calculated Daily TDS, Mean Residual = 27.5 mg/L 800 700 600 mg/L 500 400 300 200 100 0 Oct-06 Oct-08 Oct-10 Oct-12 Oct-14 6

Daily TDS at Santa Ana River at Imperial HWY near Anaheim HSPF – WY 2007 to 2016 1,000 Observed Model-Calculated Daily TDS, Mean Residual = 31.1 mg/L 900 800 700 600 mg/L 500 400 300 200 100 Model-Calculated 0 Oct-06 Oct-08 Oct-10 Oct-12 Oct-14 7

Daily TIN at Santa Ana River at MWD Crossing R4 – WY 1995 to 2006 16 Model-Calculated Daily TIN, 14 Mean Residual = -0.45 mg/L 12 Observed 10 mg/L 8 6 4 2 Model-Calculated 0 Oct-94 Oct-96 Oct-98 Oct-00 Oct-02 Oct-04 HSPF – WY 2007 to 2016 16 Model-Calculated Daily TIN, Mean Residual = 0.32 mg/L 14 12 10 mg/L 8 6 4 2 0 Oct-06 Oct-08 Oct-10 Oct-12 Oct-14 8

Daily TIN at Santa Ana River below Prado R4 – WY 1995 to 2006 16 14 Model-Calculated Daily TIN, Mean Residual = -0.07 mg/L 12 Observed 10 mg/L 8 6 4 2 Model-Calculated 0 Oct-94 Oct-96 Oct-98 Oct-00 Oct-02 Oct-04 HSPF – WY 2007 to 2016 16 Mean Residual = 0.02 mg/L 14 Model-Calculated Daily TIN, 12 10 mg/L 8 6 4 2 0 Oct-06 Oct-08 Oct-10 Oct-12 Oct-14 9

Daily TIN at Santa Ana River at Imperial HWY near Anaheim HSPF – WY 2007 to 2016 16 Model-Calculated Daily TIN, 14 Mean Residual = -0.38 mg/L 12 Observed 10 mg/L 8 6 4 2 Model-Calculated 0 Oct-06 Oct-08 Oct-10 Oct-12 Oct-14 10

Next Steps Complete TDS and TIN Recalibration of WLAM • Work with SAWPA staff, Basin Monitoring Program Task Force • Representatives, and the Regional Board staff • To specify range of portable discharge conditions including: • Maximum expected discharge of treated water under current and 2040 conditions Maximum expected re-use of recycled water under current and 2040 • conditions Effluent limits for TIN and TDS in the most recent NPDES permit • To identify percolation ponds and retention basins where treated wastewater • is regularly recharged to groundwater and where such discharge are presently governed by permits issued by the Regional Board 11

QUESTIONS? 12