Storm Water “Blue Ribbon” Panel Storm Water “Blue Ribbon” Panel Recommendations to the California Recommendations to the California

State Water Resources Control BoardState Water Resources Control Board

The Feasibility of Numeric Effluent Limits Applicable The Feasibility of Numeric Effluent Limits Applicable to Discharges of Storm Water Associated with to Discharges of Storm Water Associated with

Municipal, Industrial and Construction ActivitiesMunicipal, Industrial and Construction Activities

Panel’s Report and the Proposed Construction PermitPanel’s Report and the Proposed Construction Permit

Eric StreckerEric StreckerGeosyntec ConsultantsGeosyntec Consultants

Blue Ribbon PanelistsBlue Ribbon PanelistsBrian Currier, Brian Currier, PEPEResearch Engineer, Research Engineer,

Office of Water Programs, Office of Water Programs, California State University Sacramento, California State University Sacramento,

Sacramento, CaliforniaSacramento, California

Gary MintonGary Minton, Ph.D, PE, Ph.D, PEResource Planning Associates, Resource Planning Associates,

Seattle, WashingtonSeattle, Washington

Robert PittRobert Pitt, Ph.D., PE, Ph.D., PECudworth Professor of Urban Water Systems, Dept. Cudworth Professor of Urban Water Systems, Dept.

of Civil, Construction, and Environmental of Civil, Construction, and Environmental Engineering, University of Alabama, Engineering, University of Alabama,

TuscaloosaTuscaloosa

Larry A. RoesnerLarry A. Roesner, Ph.D., PE, Ph.D., PE.. Colorado State University, Fort Colorado State University, Fort

Collins, ColoradoCollins, Colorado

Ken SchiffKen SchiffDeputy Director, Southern California Coastal Deputy Director, Southern California Coastal

Water Research Project, Westminster, Water Research Project, Westminster, CaliforniaCalifornia

Mike StenstromMike Stenstrom, Ph.D., PE, Ph.D., PEDept. of Civil and Environmental Dept. of Civil and Environmental

Engineering, University of Engineering, University of California at Los Angeles,California at Los Angeles,

Los Angeles, CaliforniaLos Angeles, California

Eric StrasslerEric StrasslerSenior Policy Analyst, Senior Policy Analyst,

Office of Water, US USEPAOffice of Water, US USEPAWashington, DCWashington, DC

Eric StreckerEric Strecker, PE, PEPrincipal, Principal,

GeoSyntec Consultants, GeoSyntec Consultants, Portland, OregonPortland, Oregon 22

Panel of experts was asked to Panel of experts was asked to consider the following: consider the following:

““Is it technically feasible to establish numeric effluent Is it technically feasible to establish numeric effluent limitations, or some other quantifiable limit, for limitations, or some other quantifiable limit, for inclusion in storm water permits? inclusion in storm water permits?

How would such limitations or criteria be established, How would such limitations or criteria be established, and what information and data would be required?”and what information and data would be required?”

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Panel of experts was asked to Panel of experts was asked to consider the following:consider the following:

““The answers should address industrial general permits, The answers should address industrial general permits, construction general permits, and area-wide municipal permits. construction general permits, and area-wide municipal permits.

The answers should also address both technology-based limitations The answers should also address both technology-based limitations or criteria and water quality-based limitations or criteria. or criteria and water quality-based limitations or criteria.

In evaluating establishment of any objective criteria, the panel In evaluating establishment of any objective criteria, the panel should address all of the following: should address all of the following: (1) The ability of the State Water Board to establish appropriate objective (1) The ability of the State Water Board to establish appropriate objective

limitations or criteria; limitations or criteria; (2) how compliance determinations would be made; (2) how compliance determinations would be made; (3) the ability of dischargers and inspectors to monitor for compliance; and (3) the ability of dischargers and inspectors to monitor for compliance; and (4) the technical and financial ability of dischargers to comply with the (4) the technical and financial ability of dischargers to comply with the

limitations or criteria.” limitations or criteria.”

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What we were not asked to do:What we were not asked to do:

Recommend whether or not effluent limits Recommend whether or not effluent limits should be adoptedshould be adopted

Specify which technology(ies) should or Specify which technology(ies) should or should not be employedshould not be employed

Develop details regarding how to implement Develop details regarding how to implement our recommendationsour recommendations

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Construction FindingsConstruction Findings Traditional Erosion and Sediment Controls on Traditional Erosion and Sediment Controls on a site basisa site basis are are

variable in performancevariable in performance Site to site variability in TSS/Turb on natural sites is also quite highSite to site variability in TSS/Turb on natural sites is also quite high Active treatment systems, including those that use Polymers and Active treatment systems, including those that use Polymers and

sedimentation (sedimentation (and electro-flocculationand electro-flocculation) have been demonstrated to ) have been demonstrated to achieve low turbidity consistently for a wide range of stormsachieve low turbidity consistently for a wide range of storms

Other pollutants have not received enough emphasisOther pollutants have not received enough emphasis Permits do not require training or certificationPermits do not require training or certification The quality of stormwater discharges from construction sites that The quality of stormwater discharges from construction sites that

effectively employ BMPs likely varies due to site conditions such effectively employ BMPs likely varies due to site conditions such as climate, soil, and topographyas climate, soil, and topography

The States of Oregon and Washington have recently adopted The States of Oregon and Washington have recently adopted similar concepts to Action Levelssimilar concepts to Action Levels

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Panel’s Construction Panel’s Construction ConclusionsConclusions

It is the consensus of the Panel that active treatment It is the consensus of the Panel that active treatment technologies make Numeric Limits technically technologies make Numeric Limits technically feasible for pollutants commonly associated with feasible for pollutants commonly associated with stormwater discharges from construction sites (e.g. stormwater discharges from construction sites (e.g. TSS and turbidity) for TSS and turbidity) for largerlarger construction sites. construction sites.

While the Panel concludes that Numeric Limits or While the Panel concludes that Numeric Limits or Action Levels are technically feasible, the Panel has Action Levels are technically feasible, the Panel has several [13 of them] reservations and concerns several [13 of them] reservations and concerns (regarding the use of active treatment systems and (regarding the use of active treatment systems and numerical effluent limits) numerical effluent limits)

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ConstructionConstruction However, setting an “upset” (Action) value is However, setting an “upset” (Action) value is

possible using:possible using: Consensus value (e.g. 100 ppb dissolved Cu is too Consensus value (e.g. 100 ppb dissolved Cu is too

much)much) Percentile of observed valuesPercentile of observed values Statistically-based population parameters of observed Statistically-based population parameters of observed

valuesvalues

“…“…identify the [statistically derived] point at which identify the [statistically derived] point at which managers feel concentrations are significantly beyond managers feel concentrations are significantly beyond the norm”the norm”

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Percentile of observed valuesPercentile of observed values

95% Value95% Value

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Statistically-based population Statistically-based population parameters of observed valuesparameters of observed values

e.g. two standard deviations above the mean e.g. two standard deviations above the mean concentrationconcentration

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Include Exceedance Storm or Include Exceedance Storm or IntensityIntensity

Concept that BMPs sizing is importantConcept that BMPs sizing is important Agencies [Agencies [or othersor others] should not be ] should not be

accountable for water quality in volumes or accountable for water quality in volumes or flows above a set design levelflows above a set design level

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Reservations and ConcernsReservations and Concerns Consideration should be given to the seasonality of Consideration should be given to the seasonality of

applying Numerical Limits. (don’t de-incentive applying Numerical Limits. (don’t de-incentive grading timing).grading timing).

Apply to construction sites with exposed graded areas, Apply to construction sites with exposed graded areas, not ones that have been stabilized not ones that have been stabilized

Where Numeric Limits are not feasible employ Action Where Numeric Limits are not feasible employ Action Levels for sites where only traditional erosion and Levels for sites where only traditional erosion and sediment controls are applied or construction sites that sediment controls are applied or construction sites that are considered “stabilized” for the runoff season. are considered “stabilized” for the runoff season.

An Action Level indicates a failure of BMPs An Action Level indicates a failure of BMPs (within some storm size limits).(within some storm size limits).

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Reservations and ConcernsReservations and Concerns

The Board should consider Numeric Limits or Action The Board should consider Numeric Limits or Action Levels for other pollutants of relevance to Levels for other pollutants of relevance to construction sites, but in particular pH.construction sites, but in particular pH.

The Board should consider the phased The Board should consider the phased implementation of Numeric Limits and Action implementation of Numeric Limits and Action Levels, commensurate with the capacity of the Levels, commensurate with the capacity of the dischargers and support industry to respond. dischargers and support industry to respond.

The Panel recommends that a Numeric Limit or The Panel recommends that a Numeric Limit or Action Level should be compared to the average Action Level should be compared to the average discharge concentration. discharge concentration.

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Reservations and ConcernsReservations and Concerns

The Board should set different Action Levels that The Board should set different Action Levels that consider the site’s climate region, soil condition, and consider the site’s climate region, soil condition, and slopes, and natural background conditions (e.g. slopes, and natural background conditions (e.g. vegetative cover) as appropriate and as data is vegetative cover) as appropriate and as data is available. available.

The Board should consider whether the Numeric The Board should consider whether the Numeric Limits or Action Levels should differ between Limits or Action Levels should differ between receiving waters that are water quality limited with receiving waters that are water quality limited with respect to turbidity, sediment or other pollutants respect to turbidity, sediment or other pollutants associated with construction, from those water bodies associated with construction, from those water bodies that are not water quality limited.that are not water quality limited.

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Reservations and ConcernsReservations and Concerns The Panel recommends that Numeric Limits and The Panel recommends that Numeric Limits and

Action Levels not apply to storms of unusual event Action Levels not apply to storms of unusual event size and/or pattern (e.g. flood events). The size and/or pattern (e.g. flood events). The determination of Water Quality Capture Volume determination of Water Quality Capture Volume should consider the differing climate regions to should consider the differing climate regions to specify these events. specify these events.

The Board should set Numeric Limits and Action The Board should set Numeric Limits and Action Levels to encourage loading reductions as appropriate Levels to encourage loading reductions as appropriate as opposed to only numeric concentrations. as opposed to only numeric concentrations. phased construction (e.g. limited exposed soil areas or their phased construction (e.g. limited exposed soil areas or their

duration), infiltration, and spraying captured runoff in duration), infiltration, and spraying captured runoff in vegetated areas as means to reduce loading.vegetated areas as means to reduce loading.

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Reservations and ConcernsReservations and Concerns The Panel is concerned that the monitoring of The Panel is concerned that the monitoring of

discharges to meet either the Action Levels or discharges to meet either the Action Levels or Numeric Limits may be costly. The Panel Numeric Limits may be costly. The Panel recommends that the Board consider this aspect.recommends that the Board consider this aspect.

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Reservations and Concerns Reservations and Concerns (Industrial)(Industrial)

The Panel recognizes the inadequacy of current The Panel recognizes the inadequacy of current monitoring data sets and recommends improved monitoring data sets and recommends improved monitoring to collect data useful for establishing monitoring to collect data useful for establishing Numeric Limits and Action Levels. Numeric Limits and Action Levels.

Insofar as possible, the Panel prefers the use of Insofar as possible, the Panel prefers the use of California data in setting Numeric Limits and Action California data in setting Numeric Limits and Action Levels. Levels.

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SummarySummaryBlue Ribbon Panel vs. Proposed PermitBlue Ribbon Panel vs. Proposed Permit

Many of our recommendations have been implemented in the permitMany of our recommendations have been implemented in the permit Differences:Differences:

Using monitoring data or consensus approach to set NALs that are Using monitoring data or consensus approach to set NALs that are “significantly beyond the norm”“significantly beyond the norm”

Including a compliance assessment (design) storm as recommended for NALs Including a compliance assessment (design) storm as recommended for NALs and NELs (i.e. should not be responsible during “flood events” for and NELs (i.e. should not be responsible during “flood events” for NALs/NELs)NALs/NELs)

With exception of the use of ATS, panel found NELs not technically feasible With exception of the use of ATS, panel found NELs not technically feasible at this time for construction sitesat this time for construction sites

We recommended the need for more comprehensive and planned We recommended the need for more comprehensive and planned monitoring (in Industrial section, but applicable to all)monitoring (in Industrial section, but applicable to all)

Could reconvene Panel to address additional technical questions, Could reconvene Panel to address additional technical questions, new information and potential approachesnew information and potential approaches

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