Urban Stormwater Management in the United States

1
Urban Stormwater Management in the United States

• National Research Council Report
• The National Academies Press
• October 2008
• NAFSMA Conference Call
• November 12, 2008

2
Outline

• Study Objectives
• Brief Summary of Major Findings
• Brief Summary of Major Recommendations
• Possible Implications for Key Areas
• Office of Waters Action Plan

3
Study Objectives

• (1) Clarify the mechanisms by which pollutants
  in stormwater discharges affect ambient water
  quality criteria and define the elements of a
  protocol to link pollutants in stormwater
  discharges to ambient water quality criteria.
• (2) Consider how useful monitoring is for both
  determining the potential of a discharge to
  contribute to a water quality standards violation
  and for determining the adequacy of stormwater
  pollution prevention plans. What specific
  parameters should be monitored and when and
  where? What effluent limits and benchmarks are
  needed to ensure that the discharge does not
  cause or contribute to a water quality standards
  violation?

4
Study Objectives

• (3) Assess and evaluate the relationship between
  different levels of stormwater pollution
  prevention plan implementation and in-stream
  water quality, considering a broad suite of best
  management practices (BMPs).
• (4) Make recommendations for how to best
  stipulate provisions in stormwater permits to
  ensure that discharges will not cause or
  contribute to exceedances of water quality
  standards. This should be done in the context of
  general permits. As a part of this task, the
  committee will consider currently available
  information on permit and program compliance.
• (5) Assess the design of the stormwater
  permitting program under the CWA.

5
Summary of Major Findings

• Perhaps most problematic is that the
  requirements governing stormwater dischargers
  leave a great deal of discretion to the
  dischargers themselves in developing stormwater
  pollution prevention plans and self-monitoring to
  ensure compliance.

6
Summary of Major Findings

• Presently the regulation of stormwater is
  hampered by a statute that focus primarily on
  specific pollutants and ignores the volume of
  discharges.

7
Summary of Major Findings

• Most stormwater discharges are regulated on an
  individual basis without accounting for the
  cumulative contributions from multiple sources in
  the same watershed.

8
Summary of Major Findings

• Implementation of the federal program has also
  been incomplete. Current statistics on the
  states implementation of the stormwater program,
  discharger compliance with stormwater
  requirements, and the ability of states and EPA
  to incorporate stormwater permits with Total
  Maximum Daily Loads are uniformly discouraging.

9
Summary of Major Findings

• Characterization data are relatively sparse for
  individual industrial operations, which makes
  these sources less amenable to generalized
  approaches based on reliable assumptions of
  pollutant types and loads.
• Many of the benchmark monitoring requirements and
  effluent guidelines for certain industrial
  subsectors are based on inaccurate and old
  information.

10
Summary of Major Recommendations

• Flow and related parameters like impervious
  cover should be considered for use as proxies for
  stormwater pollutant loading. These analogs . .
  . have great potential . . . because they provide
  specific measurable targets, . . . and focus on
  water degradation resulting from increased volume
  as well as increased pollutant loadings in
  stormwater runoff.

11
Summary of Major Recommendations

• Convert the current piecemeal system into a
  watershed-based permitting system.
• All entities in the watershed are designated for
  regulation
• Much greater responsibility falls on
  municipalities to coordinate and regulate
  industry and construction
• Compliance based on achieving watershed-specific
  objectives related to attainment of beneficial
  uses

12
Summary of Major Recommendations

• EPA should develop numerical expressions to
  represent the MS4 standard of Maximum Extent
  Practicable. This could involve establishing
  municipal action levels, developing site-based
  runoff and pollutant load limits, and setting
  turbidity limits for construction sites.

13
Summary of Major Recommendations

• EPA should engage in much more vigilant
  regulatory oversight in the national licensing of
  products that contribute significantly to
  stormwater pollution. Currently, EPA does not
  apparently utilize its existing licensing
  authority to regulate these products in a way
  that minimizes their contribution to stormwater
  contamination.

14
Summary of Major Recommendations

• Future land development and its potential
  increases must be considered and addressed in a
  stormwater regulatory program.

15
Summary of Major Recommendations

• The federal government should provide more
  financial support to state and local efforts to
  regulate stormwater.
• EPA should reassess its allocation of funds
  within the NPDES program . . . to advance the
  NPDES stormwater program.

16
Summary of Major Recommendations

• More comprehensive biological monitoring of
  waterbodies to reflect cumulative urban impacts.
• Better monitoring of MS4s to determine outcomes.
• Industry should monitor the quality of stormwater
  discharges from certain critical industrial
  sectors in a more sophisticated manner.
• Continuous, flow-weighted sampling methods should
  replace grab sampling.
• Risk-based monitoring framework.

17
Summary of Major Recommendations

• EPA should be a leader in SCM research, both
  directly by improving its internal modeling
  efforts and by funding state efforts to monitor
  and report back on the success of SCMs in the
  field.
• EPA needs to extend, develop and support
  stormwater modeling capabilities to better
  understand and eliminate stormwater discharges

18
Industrial Stormwater
19
Municipal Stormwater

• Report supports flow-oriented approaches in MS4
  permits (e.g., Ventura County, West Virginia)

20
Green Infrastructure

• SCMs that harvest, infiltrate and
  evapotranspirate stormwater are critical to
  reducing the volume and pollutant loadings of
  small storms
• Aquatic Resources Conservation Design (new term
  substitutes for LID)
• Product Substitution,
• Watershed and Land-Use Planning,
• Conservation of Natural Areas,
• Impervious Cover Minimization,
• Earthwork Minimization,
• Reforestation and Soil Conservation,
• Runoff Volume ReductionRainwater Harvesting,
  Vegetated, and Subsurface,
• Aquatic Buffers and Managed Floodplains, and
• Illicit Discharge Detection and Elimination.
• Flow Controls
• In general the report advocates the use of
  approaches and practices that are central to
  green infrastructure principles emphasizes role
  of MS4s

21
Construction Stormwater

• Supports the use of numeric limits or benchmarks
  for construction sites
• Compliance with and enforcement of a Plan based
  on the implementation of BMPs is an ineffective
  method for controlling stormwater discharges
• Cites several pollutants including toxic
  pollutants associated with construction
  discharges

22
Total Maximum Daily Loads

• Biological monitoring is critical to
  understanding the cumulative impacts of
  urbanization
• Flow and related parameters like impervious cover
  should be used as proxies for stormwater
  pollutant loading
• Need to improve models predicting links between
  stormwater discharges and downstream impacts
• Expand use of watershed-based TMDLs with
  adaptive implementation and include future
  growth allocations
• Expand use of TMDLs in threatened and
  non-impaired waters
• EPA and states need to provide more specific
  guidance for MS4s to comply with TMDL in their
  permit applications and annual reports

23
Developing an OW Action Plan

• Form cross-office (OWM, OST, OWOW, OGC, ORD,
  OECA, OPPTS . . . ) team for initial synthesis
• Compilation of report findings/conclusions
• Identify
• Where regulatory statutory changes would be
  necessary
• Feasibility of change
• Involve stakeholder groups
• One-on-one meetings
• Public listening sessions
• Request for comments in Fed. Reg.
• Develop proposed Action Plan with time frames
  (short-, medium- and long-term)

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Discussion

• General impressions of the report?
• Suggestions on Action Plan process?
• How would NAFSMA like to be involved?
• Point of contact?
• Additional meetings?
• Other questions/discussion?