2005 ANNUAL REPORT OF SANTA ANA RIVER WATER QUALITY

Transcription

1 25 ANNUAL REPORT OF SANTA ANA RIVER WATER QUALITY Final Report Prepared by:

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3 ANNUAL REPORT OF SANTA ANA WATER QUALITY TABLE OF CONTENTS TABLE OF CONTENTS 1 Introduction Data Collection Analysis of Monitoring Data Santa Ana River Reach Santa Ana River Reach Below Prado Dam Santa Ana River Mainstem between Riverside Narrows and Prado Wetlands Tributaries to Reach 3 of the Santa Ana River Chino Creek Cucamonga Creek Temescal Wash Santa Ana River Reach Santa Ana River Reach Summary i

4 ANNUAL REPORT OF SANTA ANA WATER QUALITY TABLE OF CONTENTS APPENDICES Appendix A ALL 25 WATER QUALITY AND FLOW DATA (INCLUDED ON ENCLOSED CD)... A-1 ii

5 ANNUAL REPORT OF SANTA ANA WATER QUALITY TABLE OF CONTENTS LIST OF TABLES Table 2-1. OCWD s Santa Ana Water Quality Monitoring Locations Table 2-2. USGS Stream Gauge Stations Table 2-3. Hydraulic Control Monitoring Program (HCMP) Monitoring Sites Table 2-4. Non-Tributary Discharges Table 3-1. Monthly Volume-Weighted Average TDS at Below Prado Dam Table 3-2. Results of RWQCB 25 Annual Baseflow Monitoring Program for the Santa Ana River at Below Prado Dam Table 3-3. Historical Results of RWQCB Annual Baseflow Monitoring Program for the Santa Ana River at Below Prado Dam Table 3-4. Summary of All Water Quality Observations for the Santa Ana River at Below Prado Dam Table 3-5. Summary of Water Quality Observations for the Santa Ana River between Riverside Narrows and Prado Wetlands Table 3-6. Baseflow Water Quality Observations for the Santa Ana River between Riverside Narrows and Prado Wetlands (August - September 25) Table 3-7. Annual Recycled Water Discharge to Santa Ana River Reach 3 and Associated Average Water Quality for Parameters of Interest Table 3-8. Summary of Water Quality and Flow Observations for Chino Creek, Table 3-9. Reach 1B Annual Discharges of Flow and Average Water Quality to Chino Creek, Reach Table 3-1. Summary of Water Quality and Flow Observations for Chino Creek, Reach Table Annual Discharges of Flow and Average Water Quality to Chino Creek, Reach Table Summary of Water Quality and Flow Observations for Cucamonga Creek Table Annual Discharges of Flow and Average Water Quality to Cucamonga Creek Table Summary of Water Quality and Flow Observations for Temescal Creek Table Annual Discharges of Flow and Average Water Quality to Temescal Creek Table Summary of Water Quality and Flow Observations for Santa Ana River Reach Table Annual Discharges of Flow and Average Water Quality to Santa Ana River Reach Table Summary of Water Quality and Flow Observations for Santa Ana River Reach Table Annual Discharges of Flow and Average Water Quality to San Timoteo Wash iii

6 ANNUAL REPORT OF SANTA ANA WATER QUALITY TABLE OF CONTENTS LIST OF FIGURES Figure 2-1a. Surface Water Monitoring Locations Figure 2-1b. Non-Tributary Dischargers Figure 3-1. Total dissolved Solids (TDS) at Below Prado Dam Figure 3-2. Total Nitrogen (TN) Below Prado Dam Figure 3-3. Boron (B) Below Prado Dam Figure 3-4. Chloride (Cl) Below Prado Dam Figure 3-5. Chemical Oxygen Demand (COD) Below Prado Dam Figure 3-6. Sodium (Na) Below Prado Dam Figure 3-7. Sulfate (SO4) Below Prado Dam Figure 3-8. Total Hardness (Hard) Below Prado Dam Figure 3-9. Total Dissolved Solids (TDS) at MWD Crossing Figure 3-1. Total Nitrogen (TN) and Total Inorganic Nitrogen (TIN) at MWD Crossing Figure Boron (B) at MWD Crossing Figure Chloride (Cl) at MWD Crossing Figure Chemical Oxygen Demand (COD) at MWD Crossing Figure Sodium (Na) at MWD Crossing Figure Sulfate (SO4) at MWD Crossing Figure Total Hardness (Hard) at MWD Crossing iv

7 ANNUAL REPORT OF SANTA ANA WATER QUALITY TABLE OF CONTENTS Acronym and Abbreviations List Acre-ft/yr AF CBWM CCWRF COD DHS EC EMWD EPA EVMWD HCMP IEUA JCSD LLWD MG ug/l mg/l umho/cm MWD NTU OCWD RCSD RIX RWQCB acre-feet per year acre-feet Chino Basin Watermaster Carbon Canyon Water Reclamation Facility chemical oxygen demand California Department of Health Services electrical conductivity Eastern Municipal Water District Environmental Protection Agency Elsinore Valley Municipal Water District Hydraulic Control Monitoring Program Inland Empire Utilities Agency Jurupa Community Services District Lee Lake Water District million gallons micrograms per liter milligrams per liter micromhos per cubic centimeter Metropolitan Water District of Southern California nephelometric turbidity units Orange County Water District Rubidoux Community Services District Rapid Infiltration and Extraction Facility Regional Water Quality Control Board, Santa Ana Region v

8 ANNUAL REPORT OF SANTA ANA WATER QUALITY TABLE OF CONTENTS Acronym and Abbreviations List RWQCP RWWRF SAR SAWPA SWP TDS TKN TIN TN TOC TSS USGS WMWD WRCRWTP WRF WRP WWTF WWTP YVWD Regional Water Quality Control Plant Regional Wastewater Reclamation Facility Santa Ana River Santa Ana Watershed Project Authority State Project Water total dissolved solids total Kjeldahl nitrogen total inorganic nitrogen total nitrogen total organic carbon total suspended solids U.S. Geological Survey Western Municipal Water District Western Riverside County Regional Wastewater Treatment Plant Water Reclamation Facility Water Reclamation Plant Wastewater Treatment Facility Wastewater Treatment Plant Yucaipa Valley Water District vi

9 SECTION 1 INTRODUCTION 1 Introduction In 1996, the Nitrogen and Total Dissolved Solids (N/TDS) Task Force was formed to conduct scientific investigations regarding the then existing nitrogen and TDS water quality objectives of the 1995 Water Quality Control Plan for the Santa Ana River (SAR) Basin (Region 8). This Task Force, administered by the Santa Ana Watershed Project Authority (SAWPA) was comprised of 22 water supply and wastewater agencies. The work performed by the Task Force was broken out into a number of phases. In 1993, the Final Technical Memorandum was completed which reported the results of this scientific investigation, The TIN/TDS Study Phase 2B of the Santa Ana Watershed Wasteload Allocation Investigation. As a result of this work, the Regional Water Quality Control Board staff amended the Santa Ana Watershed Water Quality Control Plan (Basin Plan). The Basin Plan Amendment (hereafter the 24 Basin Plan Amendment) was adopted by the Regional Board in January 24, approved by the State Water Resources Control Board in September 24, and approved by the Office of Administrative Law in December 24. The 24 Basin Plan Amendment states that, based on data generated during the N/TDS investigation, a conservative nitrogen-loss coefficient of 25 percent would be applied to all discharges that affect groundwater in the Region. A nitrogen-loss coefficient of 5 percent would be applied to discharges in Reach 3 of the SAR. Confirmation sampling to demonstrate nitrogen loss would be undertaken when a project proponent requests a nitrogen-loss coefficient greater than 25 percent (other than in Reach 3 of the SAR). The 5 percent loss in Reach 3 of the SAR was demonstrated by the Task Force. The demonstrations utilized site-specific data. Pursuant to the 24 Basin Plan Amendment, certain participants in the N/TDS Task Force are required to conduct the following investigations: Re-computation of Ambient Water Quality for the Period 1984 to 23; and Preparation of an Annual Report of Santa Ana River Water Quality This report fulfills the second requirement listed above Preparation of an Annual Report of Santa Ana River Water Quality. Contained within this report are water quality data required to implement the surface water monitoring program necessary to determine compliance with the nitrogen and TDS objectives of the SAR and, thereby, the effectiveness of the wasteload allocations. Within the Amendment to the Basin Plan for TDS and Nitrogen, new water quality objectives for both surface water and groundwater were defined. Under Chapter 4 of the Basin Plan, the baseflow TDS and total nitrogen objectives for Reach 3 of the River were specified. For Reach 2, a TDS objective based on a five-year, volume-weighted, moving average of the annual TDS concentration is also defined. The use of this moving average allows the effects of wet and dry years to be integrated over the five-year period and reflects the long-term quality of water recharged by Orange County Water District (OCWD) downstream of Prado Dam. The Basin Plan specifies a monitoring program to determine compliance with the Reach 3 baseflow objectives at Prado Dam (see Chapter 4 of the Basin Plan). Regional Board staff conducts this program on an annual basis. The measurement of baseflow quality, rather than the 1-1

10 SECTION 1 INTRODUCTION quality of flows in Reach 2, has long been used to indicate the effects of recharge of SAR flows on Orange County groundwater. The efficacy of this approach was evaluated as part of the 24 Basin Plan Amendment for the TDS/nitrogen management plan in the Basin Plan. As discussed in the 24 Basin Plan Amendment, Reach 3 baseflow objectives are considered protective of the Orange County Groundwater Basin and the existing monitoring program designed to measure compliance is sufficient. In addition to the baseflow sampling program and the surface water monitoring commitments associated with certain agencies maximum benefit programs, the comprehensive monitoring program implemented by the Task Force members must include an evaluation of compliance with the TDS and nitrogen objectives for Reaches 2, 4, and 5 of the SAR. Compliance with the Reach 2 TDS objective can be determined by the evaluation of data collected by the SAR Watermaster, OCWD, the United States Geological Survey (USGS), and others. Compliance with Basin Plan objectives for Reach 4 and 5 of the Santa Ana River can be determined in the same manner. A description of the data collected for this report is discussed in Section 2. Section 3 presents the analysis of the monitoring data collected. Results are presented by Reach of the SAR, followed by non-tributary discharges to the River. Water quality and flow data were also collected from tributaries to the SAR and, where appropriate, were compared to Basin Plan Objectives to determine compliance. Section 4 provides a summary of the report. The complete set of 25 surface water quality and POTW discharge data is included as Appendix A on the enclosed CD. 1-2

11 SECTION 2 DATA COLLECTION 2 Data Collection Water quality and discharge data used to prepare the 25 Annual Report of Santa Ana Water Quality were collected from a number of regional efforts to monitor surface water quality along the Santa Ana River and its tributaries including in-stream gauges employed by USGS. Additional sources of data included non-tributary discharges from water recycling facilities and imported water releases to the Santa Ana River and its tributaries. Surface water quality monitoring locations including USGS flow gauging stations are shown in Figure 2-1a, and other non-tributary discharge points are shown in Figure 2-1b. A detailed description of each of these monitoring efforts follows: The Santa Ana Regional Water Quality Control Board (RWQCB) staff conducts annual water quality monitoring of baseflow in the Santa Ana River exiting Reach 3, below Prado Dam. Monitoring extends over a four- to eight-week period during the months of August and September. Monitoring results are used to determine compliance with Reach 3 baseflow objectives. In 25, baseflow monitoring consisted of eight sampling events from August 11 through August 31. The complete set of 25 baseflow water quality data collected exiting Reach 3 below Prado Dam by the RWQCB is included in Appendix A on the enclosed CD. OCWD conducts a monitoring program for the Santa Ana River to assess the quality of the Santa Ana River water recharged into the Orange County Groundwater Basin. OCWD collects monthly samples from the Santa Ana River at Imperial Highway in Anaheim, and quarterly and annual samples from other locations along the Santa Ana River (both above and below Prado Dam) and its tributaries. During the month of August, monitoring is performed with a greater sampling frequency to capture base flow conditions within the watershed. These data are used to evaluate water quality for Reaches 2, 3, and 4 of the Santa Ana River and Reach 1B of Chino Creek. OCWD monitoring locations used in this report are presented in Table 2-1. In later tables and figures, OCWD stations are referred to by their map location. The complete set of 25 Santa Ana River water quality data collected by the OCWD is included in Appendix A on the enclosed CD. 2-1

12 SECTION 2 DATA COLLECTION Table 2-1. OCWD s Santa Ana Water Quality Monitoring Locations Station ID Station Name Tributary 815 SAR-BELOWDAM-1 Santa Ana River Reach SAR-RIVERRD-1 Santa Ana River Reach SAR-HAMNER-1 Santa Ana River Reach SAR-ETIWANDA-1 Santa Ana River Reach SAR-VANBUREN-2 Santa Ana River Reach SAR-VANBUREN-1 Santa Ana River Reach SAR-MWDXING-1 Santa Ana River Reach CK-CHINO-3 Chino Creek 89 CK-MILL-1 Mill Creek CK-CUCAMONGA-2 Cucamonga Creek 817 CK-TEMESCAL-2 Temescal Creek 8114 SAR-MISSION-1 Santa Ana River Reach SAR-RIVERSIDEAVE-1 Santa Ana River Reach SAR-LACADENA-1 Santa Ana River Reach SAR-WATERMAN-1 Santa Ana River Reach 5 The USGS maintains seven active gauging stations to monitor flow and water quality along the Santa Ana River and several of its tributaries. Long-term streamflow and water quality data are available for gauging stations 1174, located at Below Prado Dam, and gauging station , located at MWD Crossing. Data available from the other gauging stations, however, includes only stream flow and are used only to provide information on annual stream flow at various locations throughout the watershed. The complete list of USGS gauging stations used in this report is presented in Table 2-2. The complete set of 25 flow and water quality data available from the USGS is included in Appendix A on the enclosed CD. 2-2

13 SECTION 2 DATA COLLECTION Table 2-2. USGS Stream Gauge Stations USGS ID Station Name 25 Flow (AFY) Tributary 1174 Santa Ana River Below Prado Dam 584,221 Santa Ana River Reach Santa Ana River at MWD Crossing 318,621 Santa Ana River Reach * Cucamonga Creek near Mira Loma* 74,785 Cucamonga Creek Chino Creek at Schaefer Avenue near Chino Temescal Creek above Main Street at Corona Santa Ana River at E St near San Bernardino 27,257 Chino Creek 77,113 Temescal Creek 176,54 Santa Ana River Reach San Timoteo Creek near Loma Linda 14,885 San Timoteo Creek * Gauge Station (Cucamonga Creek near Mira Loma) had available data for only 1/1/25 through 9/3/25 (end of water year). All other Gauge stations include data for the full 25 calendar year The Hydraulic Control Monitoring Program (HCMP) is conducted jointly by the Chino Basin Watermaster (CBWM) and Inland Empire Utility Agency (IEUA) as part of their Maximum Benefit monitoring commitment. Water quality data collected through this program is used to evaluate compliance with Basin Plan objectives for Reaches 2 and 3 of the SAR. The HCMP program collects monthly and bi-monthly samples from locations along the SAR (both above and below Prado Dam) and its tributaries. HCMP monitoring locations used in this report are presented in Table 2-3. The complete set of 25 water quality data collected through the HCMP is included in Appendix A on the enclosed CD. 2-3

14 SECTION 2 DATA COLLECTION Table 2-3. Hydraulic Control Monitoring Program (HCMP) Monitoring Sites Station ID Site Name Tributary SANTA ANA RIVER BELOW PRADO DAM Santa Ana River Reach SANTA ANA RIVER AT RIVER ROAD Santa Ana River Reach SANTA ANA RIVER AT HAMNER Santa Ana River Reach SANTA ANA RIVER AT ETIWANDA Santa Ana River Reach HOLE LAKE OUTLET CHANNEL NEAR ARLINGTON Santa Ana River Reach SANTA ANA RIVER AT VAN BUREN Santa Ana River Reach SANTA ANA RIVER AT MWD CROSSING Santa Ana River Reach CHINO CREEK AT SCHAEFER Santa Ana River Reach CUCAMONGA CREEK NEAR MIRA LOMA Cucamonga Creek CUCAMONGA CREEK ABOVE ELY BASIN Cucamonga Creek TEMESCAL CHANNEL ABOVE MAIN AT CORONA Temescal Creek Data for non-tributary discharges were compiled from individual communications with facility operators and from data made available from the SAR Watermaster. This includes discharge monitoring report data from seventeen facilities producing recycled water and the Arlington desalter, which may also discharge to the system. Additionally included under this category are records maintained by OCWD of imported water released at OC-59 located on San Antonio Creek. Non-tributary discharges are listed in Table 2-4. The complete set of 25 discharge water quality data compiled for this report is included in Appendix A on the enclosed CD. 2-4

15 SECTION 2 DATA COLLECTION Table 2-4. Non-Tributary Discharges Recycled Water Discharger City of Riverside Public Works Department Western Municipal Water District Inland Empire Utilities Agency Inland Empire Utilities Agency Inland Empire Utilities Agency Inland Empire Utilities Agency Western Municipal Water District Eastern Municipal Water District Elsinore Valley Municipal Water District City of Corona Public Works Department Recycled Water Facility City of Riverside Regional Water Quality Control Plant Western Riverside County Regional Wastewater Treatment Plant IEUA RP-1 Cucamonga IEUA RP-1 El Prado IEUA RP-5 IEUA Carbon Canyon Water Reclamation Facility WMWD Arlington Desalter EMWD Wastewater Treatment Plant EVMWD Regional Water Reclamation Facility City of Corona Wastewater Treatment Plant 1B Receiving Water Santa Ana River Reach 2 Santa Ana River Reach 3 Cucamonga Creek Chino Creek Chino Creek Chino Creek Temescal Creek Temescal Creek Temescal Creek Temescal Creek Lee Lake Water District LLWD Wastewater Treatment Plant Temescal Creek City of San Bernardino Water Department City of Rialto Public Works Department City of Colton Public Works Department Rubidoux Community Services District City of San Bernardino Water Department Yucaipa Valley Water District City of Beaumont Public Works Department Orange County Water District City of San Bernardino Rapid Infiltration Facility (RIX) Santa Ana River Reach 4 City of Rialto Wastewater Treatment Plant Santa Ana River Reach 4 City of Colton Waste Water Treatment Facility Santa Ana River Reach 4 RCSD Nitrate Plant Santa Ana River Reach 4 City of San Bernardino Water Reclamation Plant Santa Ana River Reach 5 YVWD Wastewater Reclamation Facility City of Beaumont Wastewater Treatment Plant 1 OCWD - OC-59 turn out San Timoteo Creek San Timoteo Creek San Antonio Creek 2-5

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17 Figure 2-1a. Surface Water Monitoring Locations

18 Figure 2-1b. Non-Tributary Dischargers

19 3 Analysis of Monitoring Data 3.1 Santa Ana River Reach 2 Water quality objectives specified for Reach 2 of the SAR by the Basin Plan include only a TDS objective of 65 mg/l. No other water quality objectives are specified for Reach 2. The TDS objective of 65 mg/l is based on a five-year, volume-weighted, moving average. Annual flowweighted TDS averages are reported in the Annual Reports of the SAR Watermaster. Using the same method as the Santa Ana River Watermaster, data collected from OCWD, USGS, and for the HCMP were plotted and a five-year, volume-weighted moving average was calculated to determine compliance with this objective. During the 25 calendar year, seventy-two samples were collected for TDS at Below Prado Dam. These included grab samples collected by the RWQCB, USGS, OCWD, and by CBWM/IEUA for the HCMP. From the results of these samples, electrical conductivity (EC) and TDS were graphically plotted. A linear regression of TDS versus EC yielded the following equation: TDS = (EC x.676) The coefficient of determination of the linear regression was.87, which indicates a strong correlation between TDS and EC; that is, about 87 percent of the variability in TDS is explained by this equation. Using the above equation and daily EC data from a continuous monitoring device operated by USGS, daily TDS values were calculated for the all of 25. Daily streamflow values at Below Prado Dam were multiplied by the computed TDS values and summed for each month. This total was divided by the total monthly flow in order to yield a volume-weighted average for each month. These results are shown in Table 3-1. The annual volume-weighted TDS average for 25 was 461 mg/l. A five-year, volume-weighted, moving average was calculated using these values in addition to historic flow-weighted TDS averages calculated by the SAR Watermaster. Figure 3-1 shows the time history for TDS observations (1967 to the present), the volume-weighted average TDS concentrations at Below Prado Dam (1974 to the present), the five-year moving average TDS concentration (1972 to the present), and the five-year, volume-weighted, moving average (1978 to the present). The five-year, volume-weighted, moving average for TDS is the compliance metric for Reach 2. This statistic never exceeded the Basin Plan objective of 65 mg/l for the period shown. The five-year, volume-weighted moving average TDS concentration has decreased over time from the mid 198s until about 2 when TDS concentration were observed to slightly increase. This upward trend continued until about 24 when TDS concentrations again began to decrease through to the present. During wet periods, not all of the water flowing from Prado Dam is captured for recharge in Orange County. Therefore, a volume-weighted average may not be representative of the quality of water actually recharged. For comparison, the five-year moving average TDS, based on discrete samples collected by OCWD, RWQCB, USGS, and by CBWM/IEUA for the HCMP, is plotted on Figure 3-1 as well. The volume-weighted and non-volume-weighted moving averages are quite similar. However, the five-year moving average exceeded 65 mg/l before 1976 and between 1984 and After the mid-198s, TDS concentrations decrease monotonically until 3-1

20 about 2; wherein, a slight increase in TDS concentration is observed. The non-volumeweighted moving average also began to decrease around 24, but not as significantly. 3-2

21 Table 3-1. Monthly Volume-Weighted Average TDS at Below Prado Dam Month Monthly Flow Monthly Weighted TDS Monthly Flow X TDS (cfs-days) (mg/l) Jan-1 11, ,184,65 Feb-1 2, ,78,966 Mar-1 13, ,96,324 Apr-1 9, ,658,475 May-1 7, ,67,549 Jun-1 6, ,59,28 Jul-1 5, ,386,632 Aug-1 5, ,236,321 Sep-1 5, ,544,534 Oct-1 6, ,122,74 Nov-1 7, ,22,782 Dec-1 9, ,54,846 Jan-2 8, ,79,488 Feb-2 8, ,71,627 Mar-2 8, ,768,217 Apr-2 8, ,691,15 May-2 7, ,29,119 Jun-2 6, ,665,281 Jul-2 5, ,335,48 Aug-2 6, ,67,734 Sep-2 5, ,14,789 Oct-2 5, ,413,227 Nov-2 7, ,37,829 Dec-2 13, ,31,84 Jan-3 1, ,3,58 Feb-3 19, ,172,51 Mar-3 18, ,42,587 Apr-3 14, ,79,248 May-3 11, ,19,315 Jun-3 9, ,6,45 Jul-3 6, ,89,786 Aug-3 6, ,462,935 Sep-3 6, ,44,63 Oct-3 7, ,724,891 Nov-3 8, ,369,42 Dec-3 7, ,171,63 Jan-4 11, ,171,516 Feb-4 2, ,77,23 Mar-4 11, ,754,352 Apr-4 1, ,874,881 May-4 8, ,864,51 Jun-4 5, ,385,1 Jul-4 5, ,265,82 Aug-4 4, ,879,727 Sep-4 5, ,16,322 Oct-4 28, ,317,933 Nov-4 9, ,439,844 Dec-4 16, ,971,34 Jan-5 14, ,673,765 Feb-5 54, ,371,844 Mar-5 29, ,598,17 Apr-5 14, ,871,24 May-5 12, ,255,979 Jun-5 12, ,257,422 Jul-5 1, ,165,791 Aug-5 12, ,67,158 Sep-5 7, ,425,838 Oct-5 7, ,744,27 Nov-5 4, ,91,598 Dec-5 8, ,876,81 Total 744,827 33,5,9 5-Year Volume Weighted Average TDS 446 Data before October 25 provided by Watermaster, October 25-December 25 calculated by SAWPA. 3-3

22 Figure 3-1. Total dissolved Solids (TDS) at Below Prado Dam SAR Discharge TDS - Non Weighted TDS - Non Weighted 5 yr moving average TDS - Weighted Monthly Ave TDS - Weighted 5 yr moving average Reach 3 TDS Basin Plan Objective Reach 2 TDS Basin Plan Objective 7, 6, 1 5, TDS (mg/l) 8 6 4, 3, Discharge (acre-feet/yr) 4 2, 2 1, Dec-65 Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: TDS Non-Weighted = TDS samples from RWQCB, USGS, HCMP, OCWD. TDS Weighted = Monthly flow weighted TDS calculated from EC. Data prior to October 23 from Watermaster; October 23 to December 24 from WeInc, 25 from SAWPA. 3-4

23 3.2 Santa Ana River Reach Below Prado Dam Compliance with water quality objectives for Reach 3 is determined using data collected by the RWQCB at Below Prado Dam through their annual baseflow monitoring program. Water quality objectives specified for Reach 3 of the Santa Ana River by the Basin Plan include TDS, hardness, sodium, chloride, Total Nitrogen (TN), sulfate, Chemical Oxygen Demand (COD) and boron. In 25 baseflow monitoring consisted of eight sampling events conducted during August. The results of this program are presented in Table 3-2. Table 3-2. Results of RWQCB 25 Annual Baseflow Monitoring Program for the Santa Ana River at Below Prado Dam Constituent Units Basin Plan Objectives SAR Reach 3 8/1 8/11 8/12 8/16 8/17 8/23 8/24 8/3 8/31 Boron mg/l Chemical Oxygen Demand mg/l Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids mg/l Total Hardness mg/l Total Inorganic Nitrogen mg/l Total Nitrogen mg/l Total Organic Carbon mg/l Data collected by RWQCB staff during 25 for each constituent were summarized as average annual values (based upon the August and September sampling) and compared to the Reach 3 water quality objectives. Total Organic Carbon (TOC) was included in this analysis as California Department of Health Services (DHS) is expected to finalize groundwater recharge regulations for TOC in the near future and a TOC objective may be incorporated in the Basin Plan (Hope Smythe, personal communication, 25). The results of this analysis for 25, as well as, historical summaries dating back to 1983 are summarized in Table 3-3. For 25, as shown in Table 3-3, none of constituents exceeded the water quality objectives specified in the Basin Plan. Over the twenty-three-year period that records have been maintained, these water quality objectives have only been exceeded by COD nine times, total hardness twice, sulfate twice, TDS once, and TN seven times. These exceedances are shown in red lettering in Table 3-3. Note, however, that no water quality objective has been exceeded since

24 Table 3-3. Historical Results of RWQCB Annual Baseflow Monitoring Program for the Santa Ana River at Below Prado Dam Year Boron (mg/l) Chemical Oxygen Demand (mg/l) Chloride (mg/l) Sodium (mg/l) Sulfate (mg/l) Total Dissolved Solids (mg/l) Total Hardness (mg/l) Total Nitrogen (mg/l) Total Organic Carbon (mg/l) na na na na na na na na na * * Basin Plan Objective *Flow-weighted adjusted values, with the exception of COD and TN, to account for State Project Water (SWP) water delivered during RWQCB s annual baseflow monitoring period. A summary of all monitoring data collected by the RWQCB, USGS, OCWD, and CBWM/IEUA at Below Prado Dam during 25 along with Basin Plan objectives for Santa Ana River Reach 3 water quality are presented in Table 3-4. This data includes the eight monitoring events conducted by the RWQCB for their annual water quality monitoring of baseflow in the SAR during August 25. CBWM/IEUA through the HCMP conducted near monthly monitoring at Below Prado Dam during 25, collecting fifteen samples during 25. OCWD conducted seventeen monitoring events at Below Prado Dam, including seven monitoring events conducted in August and September 25. The USGS conducted limited sampling at Below Prado Dam collecting four samples during August and September

25 Table 3-4. Summary of All Water Quality Observations for the Santa Ana River at Below Prado Dam Constituent Units Basin Plan Objectives SAR Reach 3 Annual Average Boron mg/l Chemical Oxygen Demand mg/l Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids mg/l Total Hardness mg/l Total Inorganic Nitrogen mg/l Total Nitrogen mg/l Total Organic Carbon mg/l A long time-history of water quality data has been collected by USGS along with data collected by OCWD, RWQCB baseflow monitoring program, and by CBWM/IEUA at Below Prado Dam and MWD Crossing. These data were plotted for each constituent that has a Basin Plan objective and are shown in Figures 3-2 through Figures 3-2 through 3-16 show baseflow and nonbaseflow water quality samples, as well as five-year moving averages to show longer-term trends in baseflow data. 3-7

26 Figure 3-2. Total Nitrogen (TN) Below Prado Dam 35 3 SAR Discharge Baseflow TN Baseflow TN 5 yr moving average Non-Baseflow TN TN Baseflow Basin Plan Objective 7, 6, 25 5, TN (mg/l) , 3, Discharge (acre-feet/yr) 1 2, 5 1, Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = TN samples from RWQCB, USGS, HCMP, OCWD for August and September. Non-Baseflow = TN samples from RWQCB, USGS, HCMP, OCWD for all months except August and September. 3-8

27 Figure 3-3. Boron (B) Below Prado Dam 6 5 SAR Discharge BaseFlow B Baseflow B 5 yr moving average Non-Baseflow B B Baseflow Basin Plan Objective 7, 6, 4 5, B (ug/l) 3 2 4, 3, 2, Discharge (acre-feet/yr) 1 1, Dec-65 Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = B samples from RWQCB, USGS, HCMP, OCWD for August and September. Non-Baseflow = B samples from RWQCB, USGS, HCMP, OCWD for all months except August and September. 3-9

28 Figure 3-4. Chloride (Cl) Below Prado Dam SAR Discharge BaseFlow Cl Baseflow Cl 5 yr moving average Non-Baseflow Cl Cl Baseflow Basin Plan Objective 7, 6, 14 5, Cl (mg/l) , 3, Discharge (acre-feet/yr) 6 2, 4 2 1, Dec-65 Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = Cl samples from RWQCB, USGS, HCMP, OCWD for August and September. Non-Baseflow = Cl samples from RWQCB, USGS, HCMP, OCWD for all months except August and September. 3-1

29 Figure 3-5. Chemical Oxygen Demand (COD) Below Prado Dam 3 25 SAR Discharge Baseflow COD Baseflow COD 5 yr moving average Non-Baseflow COD COD Baseflow Basin Plan Objective 7, 6, 2 5, COD (mg/l) , 3, 2, Discharge (acre-feet/yr) 5 1, Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = COD samples from RWQCB, USGS, HCMP, OCWD for August and September. Non-Baseflow = COD samples from RWQCB, USGS, HCMP, OCWD for all months except August and September. 3-11

30 Figure 3-6. Sodium (Na) Below Prado Dam SAR Discharge Baseflow Na Baseflow Na 5 yr moving average Non-Baseflow Na Na Baseflow Basin Plan Objective 7, 6, Na (mg/l) , 4, 3, 2, Discharge (acre-feet/yr) 2 1, Dec-65 Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = Na samples from RWQCB, USGS, HCMP, OCWD for August and September. Non-Baseflow = Na samples from RWQCB, USGS, HCMP, OCWD for all months except August and September. 3-12

31 Figure 3-7. Sulfate (SO4) Below Prado Dam 25 2 SAR Discharge Baseflow SO4 Baseflow SO4 5 yr moving average Non-Baseflow SO4 SO4 Baseflow Basin Plan Objective 7, 6, 5, Na (mg/l) , 3, Discharge (acre-feet/yr) 2, 5 1, Dec-65 Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = SO4 samples from RWQCB, USGS, HCMP, OCWD for August and September. Non-Baseflow = SO4 samples from RWQCB, USGS, HCMP, OCWD for all months except August and September. 3-13

32 Figure 3-8. Total Hardness (Hard) Below Prado Dam 6 5 SAR Discharge Baseflow Hardness Baseflow Hardness 5 yr moving average Non-Baseflow Hardness Hardness Baseflow Basin Plan Objective 7, 6, 4 5, Hardness (mg/l) 3 2 4, 3, 2, Discharge (acre-feet/yr) 1 1, Dec-65 Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = Hardness samples from RWQCB, USGS, HCMP, OCWD for August and September. Non-Baseflow = Hardness samples from RWQCB, USGS, HCMP, OCWD for all months except August and September. 3-14

33 Figure 3-9. Total Dissolved Solids (TDS) at MWD Crossing MWD Xing Discharge Baseflow TDS Baseflow TDS 5 yr moving average Non-Baseflow TDS TDS Baseflow Basin Plan Objective 35, 3, 7 25, TDS (mg/l) , 15, Discharge (acre-feet/yr) 3 1, 2 5, 1 Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Notes: Baseflow = TDS samples from USGS, HCMP, OCWD for August and September. Date Non-Baseflow = TDS samples from USGS, HCMP, OCWD for all months except August and September. 3-15

34 Figure 3-1. Total Nitrogen (TN) and Total Inorganic Nitrogen (TIN) at MWD Crossing MWD Xing Discharge Baseflow TN Baseflow TN 5 yr moving average Non-Baseflow TN Non-Baseflow TIN TN Baseflow Basin Plan Objective 35, 3, 12 25, TN (mg/l) , 15, Discharge (acre-feet/yr) 4 1, 2 5, Dec-7 Dec-75 Dec-8 Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = TN samples from USGS, HCMP, OCWD for August and September. Non-Baseflow = TN samples from USGS, HCMP, OCWD for all months except August and September. 3-16

35 Figure Boron (B) at MWD Crossing 25 2 MWD Xing Discharge Baseflow B Baseflow B 5 yr moving average Non-Baseflow B B Baseflow Basin Plan Objective 35, 3, 25, B (ug/l) , 15, Discharge (acre-feet/yr) 1, 5 5, Dec-85 Dec-9 Dec-95 Dec- Dec-5 Notes: Baseflow = B samples from USGS, HCMP, OCWD for August and September. Non-Baseflow = B samples from USGS, HCMP, OCWD for all months except August and September. Date 3-17

36 Figure Chloride (Cl) at MWD Crossing MWD Xing Discharge Baseflow Cl Baseflow Cl 5 yr moving average Non-Baseflow Cl Cl Baseflow Basin Plan Objective 35, 3, 12 25, Cl (mg/l) 1 8 2, 15, Discharge (acre-feet/yr) 6 1, 4 2 5, Dec-85 Dec-9 Dec-95 Dec- Dec-5 Notes: Baseflow = Cl samples from USGS, HCMP, OCWD for August and September. Non-Baseflow = Cl samples from USGS, HCMP, OCWD for all months except August and September. Date 3-18

37 Figure Chemical Oxygen Demand (COD) at MWD Crossing MWD Xing Discharge Baseflow COD Baseflow COD 5 yr moving average Non-Baseflow COD COD Baseflow Basin Plan Objective 35, 3, 14 25, COD (mg/l) , 15, Discharge (acre-feet/yr) 6 1, 4 2 5, Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = COD samples from USGS, HCMP, OCWD for August and September. Non-Baseflow = COD samples from USGS, HCMP, OCWD for all months except August and September. 3-19

38 Figure Sodium (Na) at MWD Crossing 12 1 MWD Xing Discharge Baseflow Na Baseflow Na 5 yr moving average Non-Baseflow Na Na Baseflow Basin Plan Objective 35, 3, 8 25, Na (mg/l) 6 2, 15, Discharge (acre-feet/yr) 4 1, 2 5, Dec-85 Dec-9 Dec-95 Dec- Dec-5 Notes: Baseflow = Na samples from USGS, HCMP, OCWD for August and September. Non-Baseflow = Na samples from USGS, HCMP, OCWD for all months except August and September. Date 3-2

39 Figure Sulfate (SO4) at MWD Crossing 25 2 MWD Xing Discharge Baseflow SO4 Baseflow SO4 5 yr moving average Non-Baseflow SO4 SO4 Baseflow Basin Plan Objective 35, 3, 25, SO4 (mg/l) , 15, Discharge (acre-feet/yr) 1, 5 5, Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = SO4 samples from USGS, HCMP, OCWD for August and September. Non-Baseflow = SO4 samples from USGS, HCMP, OCWD for all months except August and September. 3-21

40 Figure Total Hardness (Hard) at MWD Crossing 7 6 MWD Xing Discharge Baseflow Hardness Baseflow Hardness 5 yr moving average Non-Baseflow Hardness SO4 Baseflow Basin Plan Objective 35, 3, 5 25, Hardness (mg/l) 4 3 2, 15, Discharge (acre-feet/yr) 2 1, 1 5, Dec-85 Dec-9 Dec-95 Dec- Dec-5 Date Notes: Baseflow = Hardness samples from USGS, HCMP, OCWD for August and September. Non-Baseflow = Hardness samples from USGS, HCMP, OCWD for all months except August and September. 3-22

41 3.2.2 Santa Ana River Mainstem between Riverside Narrows and Prado Wetlands Monitoring of Reach 3, above Prado Dam is preformed regularly by OCWD for their SAR water quality monitoring program and by CBWM/IEUA for the HCMP. This included monitoring of the following locations: At MWD Crossing, Van Buren Blvd, Hole Lake Outlet, Etiwanda Avenue, Hamner Road, and River Road, as shown in Figure 2-1a. CBWM/IEUA through the HCMP monitors each of these locations nearly every month. Monitoring by OCWD for these locations was as follows: Etiwanda Avenue and Hamner Road were only sampled in August of 25; MWD Crossing and Van Buren Blvd were sampled monthly between March and August, with the exception of July at both sites and August at Van Buren Blvd; and River Road station was sampled bi-monthly or monthly throughout 25, except for July, and weekly in the month of August. Table 3-5 presents a summary of the results of these monitoring efforts. Overall in 25, water quality measured at locations along Reach 3 of the Santa Ana River met water quality objectives specified in the Basin Plan. In general, the trend of this data showed water quality concentrations from the MWD Crossing station downstream to the River Road station increased toward the downstream. One exception was data recorded at Hole Lake Outlet, which is tributary to the Santa Ana River. Data collected here was of poorer water quality and showed exceedences of water quality objectives specified in the Basin Plan. These included exceedances of TDS, chloride, sodium, sulfate, hardness and TN. Baseflow water quality, as represented by the average of samples collected in August and September, for the above stations is presented in Table 3-6. This data reported water quality concentrations similar to average annual water quality. Overall, average baseflow concentrations of shown in Table 3-6 met water quality objectives specified in the Basin Plan. One exception was Total hardness reported at Etiwanda Avenue (362 mg/l), which exceeded the water quality objective (35 mg/l). In addition, as reported for the annual results, data recorded at Hole Lake Outlet, tributary to the Santa Ana River showed exceedences of water quality objectives specified in the Basin Plan. These again included exceedances of TDS, chloride, sodium, sulfate, hardness and TN. 3-23

42 Table 3-5. Summary of Water Quality Observations for the Santa Ana River between Riverside Narrows and Prado Wetlands Constituent Units Basin Plan Objectives SAR Reach 3 SAR at River Road SAR at Hamner SAR at Etiwanda Hole Lake Outlet SAR at Van Buren SAR at MWD Crossing Boron mg/l Chemical Oxygen Demand mg/l na- -na Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids Total Hardness Total Inorganic Nitrogen Total Nitrogen Total Organic Carbon mg/l mg/l mg/l mg/l mg/l

43 Table 3-6. Baseflow Water Quality Observations for the Santa Ana River between Riverside Narrows and Prado Wetlands (August - September 25) Constituent Units Basin Plan Objectives SAR Reach 3 SAR at River Road SAR at Hamner SAR at Etiwanda Hole Lake Outlet SAR at Van Buren SAR at MWD Crossing Boron mg/l Chemical Oxygen Demand mg/l na- -na Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids Total Hardness Total Inorganic Nitrogen Total Nitrogen Total Organic Carbon mg/l mg/l mg/l mg/l mg/l na- -na

44 Non-tributary discharges to the SAR Reach 3 consists primarily of wastewater effluent discharges from the City of Riverside Regional Water Quality Control Plant and the Western Riverside County Regional Wastewater Treatment Plant (WRCRWTP), shown in Figure 2-1b. Table 3-7 summarizes the non-tributary discharges of flow and water quality to Reach 3 of the SAR for 25. The USGS also maintains a gauging station, , located along Reach 3 of the SAR at the MWD Crossing, shown in Figure 2-1a. In 25, this station recorded flows totaling 318,621 AF. Table 3-7. Annual Recycled Water Discharge to Santa Ana River Reach 3 and Associated Average Water Quality for Parameters of Interest Constituent Units City of Riverside Regional Water Quality Control Plant Western Riverside County Regional Wastewater Treatment Plant Discharge AFY 37,967 -na- 3,747 -na- Boron mg/l Chemical Oxygen Demand mg/l -na- -na- -na- -na- Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids mg/l Total Hardness mg/l Total Inorganic Nitrogen mg/l Total Nitrogen mg/l -na- -na- -na- -na- Total Organic Carbon mg/l

45 3.2.3 Tributaries to Reach 3 of the Santa Ana River The three tributaries to Reach 3 of the SAR that are regularly monitored for water quality and discharge by OCWD, USGS, and by CBWM/IEUA for the HCMP are Chino Creek, Cucamonga Creek (which becomes Mill Creek in the Prado reservoir area), and Temescal Wash Chino Creek Chino Creek extends from its confluence with the SAR (directly behind Prado Dam) along the eastern base of the Chino Hills and into southern Pomona. Chino Creek is divided into two reaches. Reach 1 is that portion of the creek that extends from the confluence with the SAR upstream to the beginning of the concrete-lined channel south of Los Serranos Road. In 24, Reach 1 of Chino Creek was further subdivided into two reaches, 1A and 1B. Reach 1A extends from the SAR confluence to downstream of the confluence with Mill Creek. Reach 1B extends from the confluence of Mill Creek to the beginning of the concrete-lined channel south of Los Serranos Road. Chino Creek Reach 2 extends from Los Serranos Road to the boundary of Region 8 with that of the Los Angeles Regional Water Quality Control Board (Region 4) at the Los Angeles/San Bernardino County line. Reach 2 of Chino Creek is concrete-lined along the bottom and banks throughout its length. San Antonio Creek, an important drainage feature in western Chino Basin, is tributary to Chino Creek, Reach 2 at a location just north of Chino Avenue. Chino Creek Reach 1A The Basin Plan has specified water quality objectives for Chino Creek Reaches 1A for TDS, hardness, sodium, chloride, TIN, sulfate and COD. However, there is no data collected along Chino Creek Reach 1A for it encompasses an area upstream of Prado Dam which is difficult to access and in the winter months is commonly inundated. Chino Creek Reach 1B The Basin Plan has specified water quality objectives for Chino Creek Reaches 1B for TDS, hardness, sodium, chloride, TIN, sulfate and COD. Along Chino Creek Reach 1B, OCWD monitors site, CK-CHINO-3, located north of Pine Avenue Bridge and just west of El Prado Road, shown in Figure 2-1a. In 25, this site was monitored monthly by OCWD from January through August (seven sampling events). Based upon limited available data collected by OCWD, four constituents were shown to exceed Basin Plan objectives. These constituents included TDS, chloride, sodium, and sulfate. Table 3-8 presents a summary of the results of this monitoring effort. Non-tributary discharges to Chino Creek Reach 1B include recycled water produced at two IEUA waste water treatment facilities RP-5 and RP-1 Prado, shown in Figure 2-1b. Table 3-9 summarizes the non-tributary discharges of flow and water quality to Chino Creek Reaches 1B for 25. The USGS also maintains a gauging station, , located along Chino Creek at Schaefer Avenue below the confluence with San Antonio Creek, shown in Figure 2-1a. In 25, this station recorded flows totaling 27,257 AF. 3-27

46 Table 3-8. Summary of Water Quality and Flow Observations for Chino Creek, Reach 1B Constituent Units Basin Plan Objectives Chino Creek Reach 1B Chino Creek Reach 1B Boron mg/l -- -na- -na- Chemical Oxygen Demand mg/l Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids mg/l Total Hardness mg/l Total Inorganic Nitrogen mg/l Total Nitrogen mg/l Total Organic Carbon mg/l Table 3-9. Annual Discharges of Flow and Average Water Quality to Chino Creek, Reach 1B Constituent Units IEUA RP-5 IEUA RP-1 El Prado Discharge AFY 8,482 -na- 11,768 -na- Boron mg/l Chemical Oxygen Demand mg/l -na- -na- -na- -na- Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids mg/l Total Hardness mg/l Total Inorganic Nitrogen mg/l Total Nitrogen mg/l -na- -na- -na- -na- Total Organic Carbon mg/l -na- -na- -na- -na- 3-28

47 Chino Creek Reach 2 In Reach 2 of Chino Creek, water quality samples were collected at the HCMP monitoring station Chino Creek at Schaefer Avenue, shown in Figure 2-1a. This site was monitored bimonthly throughout 25 (27 sampling events); however the Basin Plan specifies no water quality objectives for Chino Creek Reach 2. Table 3-8 presents a summary of the results of this monitoring effort. Non-tributary discharges to Chino Creek Reach 2 include recycled water produced at IEUA s Carbon Canyon Water Reclamation Facility (CCWRF) and imported SWP water released to San Antonio Creek, at turnout OC-59, shown in Figure 2-1b. Table 3-9 summarizes the non-tributary discharges of flow and water quality to Chino Creek Reach 2 for 25. Table 3-1. Summary of Water Quality and Flow Observations for Chino Creek, Reach 2 Constituent Units Chino Creek at Schaefer Ave Boron mg/l Chemical Oxygen Demand mg/l -na- -na- Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids mg/l Total Hardness mg/l Total Inorganic Nitrogen mg/l Total Nitrogen mg/l Total Organic Carbon mg/l -na- -na- 3-29

48 Table Annual Discharges of Flow and Average Water Quality to Chino Creek, Reach 2 Constituent Units IEUA - Carbon Canyon Water Reclamation Facility OCWD - OC-59 Turnout for imported water Discharge AFY 8,617 -na- 1,321 -na- Boron mg/l Chemical Oxygen Demand mg/l -na- -na- -na- -na- Chloride mg/l Sodium mg/l Sulfate mg/l Total Dissolved Solids mg/l Total Hardness mg/l na- -na- Total Inorganic Nitrogen mg/l na- -na- Total Nitrogen mg/l -na- -na- -na- -na- Total Organic Carbon mg/l -na- -na Cucamonga Creek As identified in Figure 2.1a, Cucamonga Creek is located just upstream of Chino-Corona Road and is designated as a natural channel with unlined bottom and banks. Cucamonga Creek, Reach 1 extends from this confluence to the point where 23 rd Street crosses the channel in the city of Upland. The segment of Cucamonga Creek upstream of this location is designated as Reach 2. Cucamonga Creek becomes Mill Creek just north of Chino-Corona Road and travels a couple of miles before flowing into Prado Flood Control Basin. Mill Creek extends from its confluence with Chino Creek to a location just upstream of Chino-Corona Road near the San Bernardino/Riverside County border. Water quality monitoring in Cucamonga Creek is preformed regularly by CBWM/IEUA for the HCMP and by OCWD for their SAR water quality monitoring program. This included monitoring of the following locations: Cucamonga Creek above Ely Basin, Cucamonga Creek near Mira Loma, and Mill Creek, as shown in Figure 2-1a. In 25, CBWM/IEUA through the HCMP, monitored the Cucamonga Creek above Ely Basin and Cucamonga Creek near Mira Loma sites on a bi-monthly basis (27 sampling events). OCWD monitored the Cucamonga Creek near Mira Loma (CK-CUCAMONGA_2), and Mill Creek sites on a monthly basis from January through August (seven sampling events). The Basin Plan specifies no water quality objectives for Cucamonga Creek. Table 3-12 presents a combined summary of the results of these monitoring efforts. 3-3