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Notebook Ref 6.3. Issue #6: Application of Waterbody Protection Tiers. Questions. Tier 3 discussion has been addressed separately . . . How is Tier 1 / Tier 2 protection applied?
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Notebook Ref 6.3 Issue #6:Application of Waterbody Protection Tiers
Questions • Tier 3 discussion has been addressed separately . . . • How is Tier 1 / Tier 2 protection applied? • ALL waterbodies are protected at the Tier 1 level (“existing water uses and the level of water quality necessary to protect existing uses must be maintained and protected • Tier 2 applies when “the quality of a water exceeds levels necessary to support propagation of fish, shellfish, and wildlife and recreation in and on the water” • Parameter-by-parameter or waterbody as a whole? • Parameter approach: defined set of parameters, usually considered to be the established water quality criteria, are used as antidegradation benchmarks • Waterbody approach: some type of holistic assessment or other data needed to characterize and predict changes in waterbodies (e.g., geomorphic, biological, chemical, physical)
Waterbody by Waterbody • Assigns waterbody (or specific portion) to a particular tier of protection from degradation • Based on “overall” water quality • Favored by aquatic ecologists • Lends itself to use of biological/biomonitoring data
Waterbody by Waterbody Pros Cons • Weighted assessments (biological, physical, & chemical) • Coincides best with habitat and biological assessments • Focuses resources on high quality waters • Some waters may not be adequately protected • Must decide what data is needed to make assessment • Front-loaded work need • Delay in implementation and need for procedures to address antidegradation before listing decisions are made • More potential for disputes, challenges and litigation
Pollutant by Pollutant • Level of antidegradation protection and review is decided for each pollutant separately • Case by case basis • As new discharges arise • No list for Tier 2 protection – all waters with better quality than minimum water quality criteria are protected at the Tier 2 level for each “better-quality” parameter
Pollutant by Pollutant Pros Cons • Little or no upfront workload • Better understood, more conventional, straightforward when it comes to analysis of degradation • Avoids disputes involved in making a decision on overall water quality • Can be immediately implemented, as new or increased discharges arise • Potentially more reviews • Water column data needed, uncertain how biological data can be used • Numerous pollutant-water body combinations • May not focus implementation efforts on truly high quality waters