P ROPOSED ROPOSED N UTRIENT UTRIENT TMDL TMDL S L OWER OWER S ALINAS ALINAS R IVER IVER & R & R ECLAMATION ECLAMATION C C ANAL ANAL B B ASIN ASIN , , & & THE THE M ORO ORO C C OJO OJO S LOUGH LOUGH S UBWATERSHED UBWATERSHED M ONTEREY ONTEREY C OUNTY OUNTY Agenda Item Agenda Item 9 Photo Credits: Photo Credits: Mary Hamilton Mary Hamilton Pete Osmolovsky Pete Osmolovsky & Chris & Chris Rose Rose CCRWQCB CCRWQCB Water Board TMDL Program Water Board TMDL Program Salinas River @ Salinas River @ Chualar Chualar
Staff Recommendation… Staff Recommendation… Adopt Resolution Adopt Resolution R3 R3-2013 2013-0008* 0008* * * Including Including Supplemental Supplemental Sheet w/proposed Sheet w/proposed changes changes Proposed Additions Proposed Additions to Basin Plan: to Basin Plan: 1. 1. TMDLs TMDLs and Implementation Plan for and Implementation Plan for Nitrogen Compounds & Nitrogen Compounds & Orthophosphate for lower Salinas Valley ** ** Orthophosphate for lower Salinas Valley ** ** Includes Lower Salinas River and Reclamation Canal Basin and Includes Lower Salinas River and Reclamation Canal Basin and Moro Cojo Moro Cojo Slough Slough Subwatershed Subwatershed 2
Highlights... Highlights... TMDLs are planning tools to assist TMDLs are planning tools to assist the State in creating its the State in creating its strategy strategy to to implement its water quality implement its water quality standards standards TMDLs use existing or planned regulatory measures to implement TMDLs use existing or planned regulatory measures to implement TMDL goals TMDL goals TMDL consistent with Water Board’s highest priorities TMDL consistent with Water Board’s highest priorities TMDL implementation = Compliance with Ag Order TMDL implementation = Compliance with Ag Order & NPDES permits & NPDES permits Relevant water quality objectives will take many years to achieve Relevant water quality objectives will take many years to achieve TMDL has been independently peer reviewed by scientists TMDL has been independently peer reviewed by scientists USEPA reports: TMDL meets federal requirements under CWA USEPA reports: TMDL meets federal requirements under CWA 3
TMDL project area TMDL project area 4
Backdrop: Backdrop: Nutrient Pollution (nitrogen & phosphorus) Backdrop: Backdrop: Nutrient Pollution (nitrogen & phosphorus) Excessive Nutrients may cause… Toxic Effects Toxic Effects (degradation of drinking (degradation of drinking water sources) water sources) Degradation Degradation of Aquatic Habitat of Aquatic Habitat (biostimulation biostimulation) Public Public health risks health risks and and nuisance nuisance (algal toxins algal toxins) Degradation Degradation of irrigation supply of irrigation supply (for sensitive crops (for sensitive crops) 5
Physical factors: Physical factors: Sunlight availability Sunlight availability Nutrients Nutrients substrate, temperature, substrate, temperature, (canopy, turbidity) (canopy, turbidity) hydraulics ydraulics Plant growth Plant growth DO crashes DO crashes (biostimulation biostimulation) (hypoxia) ; fish ; fish (hypoxia) kills; disruption kills; disruption of aquatic food of aquatic food Excess algal Excess algal web web biomass biomass Public nuisance Public nuisance – Dissolved Dissolved public health risks public health risks Decreased Decreased oxygen oxygen (harmful algal blooms) (harmful algal blooms) biological biological imbalances imbalances diversity diversity Example of biostimulation Example of biostimulation 6 Moro Cojo Moro Cojo Slough (Sept. 2011) Slough (Sept. 2011)
Backdrop: Backdrop: Backdrop: Backdrop: Scope of nitrate pollution Scope of nitrate pollution in surface waters in surface waters 7 7
WQ D ATA 1999-2010 No. of samples: 2,127 % > 10 mg/L: 47.3% (drinking H2O standard) % > 100 mg/L: 1.9% (livestock poisoning) Backdrop: Backdrop: Backdrop: Backdrop: 8 Nitrate pollution TMDL project area Nitrate pollution TMDL project area 8
Nutrient TMDL Development… Nutrient TMDL Development… S PRING PRING 2010 2010 THROUGH THROUGH J AN AN . 2013 . 2013 4 Public 4 Public Workshops: Workshops: June 2010, April 2011, Oct. June 2010, April 2011, Oct. 2011, Nov. 2012 2011, Nov. 2012 Data analysis, & input from stakeholders & interested parties Data analysis, & input from stakeholders & interested parties Independent Scientific Peer Review: Spring 2012 Independent Scientific Peer Review: Spring 2012 Review by SWRCB Office of Chief Counsel Review by SWRCB Office of Chief Counsel Review by USEPA Review by USEPA Public Review & Written Comments: Fall 2012 Public Review & Written Comments: Fall 2012 9
Nutrient Nutrient Impaired Waters Impaired Waters 10 10 TMDL project area TMDL project area TMDL project area TMDL project area
TMDL Source Analysis… TMDL Source Analysis… Nitrogen Sources Nitrogen Sources Phosphorus Sources Phosphorus Sources 11
Nutrient Numeric Target Development… Nutrient Numeric Target Development… Standard : : Basin Plan Nutrient Water Quality Standard Basin Plan Nutrient Water Quality Biostimulatory Biostimulatory Substances Substances ( Narrative Narrative Regulatory Standard) Regulatory Standard) “Waters shall not contain bio “Waters shall not contain bio -stimulatory substances stimulatory substances in concentrations in concentrations that promote aquatic growths to the extent that that promote aquatic growths to the extent that such such growths… affect growths… affect beneficial uses beneficial uses .” .” Staff’s Numeric Target Development Approach… Staff’s Numeric Target Development Approach… Approaches used in previous approved TMDLs; USEPA recommended methodologies; California NNE approach 12
TMDLs Summary… TMDLs Summary… Stream Stream Numeric Numeric Characterization of Numeric Characterization of Numeric Constituent Constituent Targets Targets Threshold Threshold Impairment Addressed Impairment Addressed (TMDLs) (TMDLs) (mg/L) (mg/L) Nitrate Nitrate Concentration Concentration-based based Basin Plan Objective Basin Plan Objective 10 10 Drinking water, Drinking water, (Regulatory Standard) (Regulatory Standard) groundwater recharge groundwater recharge Unionized ammonia Unionized ammonia Concentration-based Concentration based Basin Plan Objective Basin Plan Objective 0.025 0.025 (Regulatory Standard) (Regulatory Standard) Toxicity Toxicity Nitrate Nitrate Concentration Concentration-based targets derived based targets derived from from 1.4 1.4 – 8.0 8.0 USEPA & SWRCB USEPA & SWRCB-recognized recognized methods methods Biostimulation Biostimulation (non (non-regulatory TMDL Target) regulatory TMDL Target) (sci. peer reviewed) (sci. peer reviewed) (aquatic habitat) (aquatic habitat) Orthophosphate Orthophosphate Concentration-based targets derived Concentration based targets derived from from 0.07 – 0.3 0.07 0.3 USEPA & SWRCB-recognized USEPA & SWRCB recognized methods methods Biostimulation Biostimulation (non (non-regulatory TMDL Target) regulatory TMDL Target) (sci. (sci. peer reviewed) peer reviewed) (aquatic habitat) (aquatic habitat) 13 Old Salinas River Old Salinas River - biostimulation biostimulation Sept. 2006 Sept. 2006
Nutrient-Response Indicator Targets ( desired conditions) Nutrient-Response Indicator Targets ( desired conditions) Characterization of Characterization of Constituent Constituent Stream Numeric Stream Numeric Numeric Numeric Threshold Threshold Targets Targets Impairment Impairment Not Not to be depressed below to be depressed below Dissolved Oxygen Dissolved Oxygen Basin Plan Objective Basin Plan Objective 5 mg/L (WARM) 5 mg/L (WARM) Biostimulation Biostimulation (Regulatory Standard) (Regulatory Standard) 7 mg/L 7 mg/L (COLD) (aquatic habitat) (aquatic habitat) (COLD) Oxygen saturation Oxygen saturation Not to be depressed below Not to be depressed below Basin Plan Objective Basin Plan Objective Biostimulation Biostimulation 85% 85% median (Regulatory Standard) (Regulatory Standard) median (aquatic habitat) (aquatic habitat) Oxygen supersaturation Oxygen supersaturation Not to exceed Not to exceed Sci. Literature Threshold Sci. Literature Threshold Biostimulation Biostimulation 13 mg/L mg/L 13 (non (non-regulatory TMDL Target) regulatory TMDL Target) (aquatic habitat) (aquatic habitat) Chlorophyll a Chlorophyll Sci. Literature Threshold Sci. Literature Threshold Biostimulation Biostimulation 15 m g/L < 15 g/L (non (non-regulatory TMDL Target) regulatory TMDL Target) (aquatic habitat) (aquatic habitat) Microcystins Microcystins (algal toxins) Basin Plan Basin Plan Narrative Obj. Narrative Obj. (algal toxins) 0.8 m g/L g/L < 0.8 < (Calif. (Calif. OEHHA health guideline) OEHHA health guideline) Biostimulation Biostimulation 14 (non (non-regulatory TMDL Target) regulatory TMDL Target) (Toxicity- REC1) (Toxicity REC1)
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