Transcript Revising Water Quality Standards for Water

Revising Water Quality Standards for
Water-Based Recreation
Provided by
Texas Water Conservation Association
and
Water Environment Association of Texas
May 16, 2007
Topics
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Review of current standards
Areas of concern with current standards
Possibilities for improvement
Process considerations – how to move
forward?
Current Standards
 Uses limited to only two:
 Contact recreation = “swimming”
 Noncontact recreation = “boating or bank use”
(rarely used, ship channels)
 Criteria
 CR: 126 colonies E. Coli per 100 mL
 NCR: 605 col/100 mL
 EPA 1986 criteria based
on limited lake studies
 Keystone Lake
 Lake Erie
Swimming Use Applicable to All Streams?
Impacts to Water Quality Management Process
 Distorts 303(d) list
 Forces restoration activities on streams that
may not be suitable for swimming use
 Mandates load reductions on non-wastewater
sources (storm water, wildlife, etc.)
 May cause public expenditures to address nonhuman bacteria sources
 May result in TPDES permit modifications
Areas of Concern
 Not all uses addressed in current designations
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Swimming - CR
Wading – NCR, limited CR
Fishing - NCR
Boating - NCR
 Swimming Use/Criteria not appropriate for all
waters
 Exposure assumptions not considered
 Water (pathogen) ingestion rates (mL/day)
 Eye, ear, skin contact
Areas of Concern
 Frequency of use of water body not considered
 Limited epidemiological data for national
criteria
 Seasonal variations not considered
 Swimming suitability not considered
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Flow
Depth
Visibility
Temperature
 Actual pathogens not
considered
Possibilities for Improvement
 Define tiered uses
 Swimming, Wading, Fishing, and Boating
 Define associated criteria using
 Exposure rates from literature or studies:
reflective of recreational activities
 Exposure frequency and duration
i.e., designated beaches vs. urban streams
 In-state epidemiological studies
if resources available
 Support with Use Attainability Analyses (UAAs)
Possibilities for Improvement
 Include consideration of swimming suitability
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Physical limitations (depth, flow, visibility)
Water not treated for ingestion
Commercial navigation conflicts
Discharges over international border
Access, alligators and nature preserve protection
 Include seasonal use variations
 Include high flow use cut-off
There’s Hope
 Kansas Approach
 Primary Contact (depth > 18”)
 A: Designated Swimming Beach, E coli 160 cfu/dL
 B: Open access, 262 cfu/dL
 C: Not open to public, 427 cfu/dL
 Secondary Contact (depth<18”)
 A: Open access, 2,358 cfu/dL
 B: Not open to public, 3,843 cfu/dL
 19 states have seasonal criteria
 Other states have tiered uses
 Chicago is conducting epidemiology work on boating
and fishing uses
Process Considerations
 Involve Clean Rivers Program to help
 Establish regional stakeholder groups to
refine uses and to conduct required
UAA’s
 Include local input and watershed
knowledge
 Support TCEQ/HGAC epidemiological
study
 Get EPA Region 6 involved upfront
Topics



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Review of current standards
Areas of concern with current standards
Possibilities for improvement
Process considerations – how to move
forward?