SUSTAINABLE WATER BRIEFING. MWRA Advisory Board

Transcription

1 SUSTAINABLE WATER MANAGEMENT INITIATIVE BRIEFING MWRA Advisory Board November 15, 2012

2 KEY ACHIEVEMENTS Science based taxonomy of 1400 Subbasins Streamflow criteria based on science Resolution of Sf Safe Yield ild Proposed package marries science to a fair, carefully calibrated, effective public policy Will maintain the healthy streams, and y, improve degraded ones over time

3 STREAMFLOW AND SAFE YIELD Streamflow criteria govern theallocation allocation. Nimble, sub basin, seasonal Safe yield provides a backstop, ultimate safeguard If get streamflow right, ih will not need safe yield ild to meet the goal, though it will play a role in certain basins

4 SAFE YIELD New SY is statistically derived It provides a backstop Allocations are greater than proposed SY in 2 Basins, but there is a plan for addressing those basins Formula shows proposed SY above allocations in many basins, but language ensures that SY in these cases is not misconstrued

5 SafeYield and Environmental Protection WMA Safe Yield = 55% of Drought Basin Yield + Reservoir Storage Safe Yield Environmental Protection Factor (EPF) = Remaining 45% of Drought Basin Yield + Streamflow Criteria 5

6 Foundation: Preliminary USGS Study FluvialFish Fish Relative Abundance Model Highly significant variables Best Model that Included Natural Basin characteristics Net August Flow Alteration Impervious Cover Single Variables Combined Variables 1 Equation Quantile Regression Abundance Fluvial Relative Net Abs Aug PA Biological Thresholds Generalized Linear Modeling 6

7 Biological Categories e Abundance Fl luvial Relativ Fluvial Relative Abundance 5% Biological Loss 15% Biological Loss 35% Biological Loss August Percent Alteration 65% Biological Loss Sensitive spp loss Above 35% Aug Flow alt. 5 Corresponding Flow Levels More Sensitive Spp Impacts to Less Sensitive Spp 7

8 STREAMFLOW PRINCIPLES Water withdrawal responsible for a portion of problem; science allows us to pinpoint that portion Level of review and mitigation obligation vary, based upon amount of increase impact of withdrawal existing iti aquatic health Mitigation is commensurate with impact Mitigation considers cost and efficacy Science not infallible categories are a rebuttable presumption

9 Permit Tiers for Groundwater Withdrawals Standard Conditions FEASIBLE MITIGATION AND IMPROVEMENT Special Conditions Quality Natural Resource Flow Levels 4 & 5 Tier Standard Conditions 1 8 No feasible alternative source(s) Desktop Explore Evaluate & pumping minimizing implement evaluation if impacts if CFR feasible mitigation CFR in FL 4/5 or BC 1* if CFR or BC 1 3* Minimize Mitigate* FL 4&5 FL 1 5 * In consultation with agencies CFR=Coldwater Fishery Resource 9

10 Offsets/Mitigation Demand Management Ban on nonessential, outdoor water use Private well bylaw Conservation rate structure Water banking Higher water efficiency Rebates for appliances Water SupplyImprovement Enterprise account Wastewater Improvement Recharge through septic or groundwater discharge I/I removal Habitat Improvement Dam removal Land acquisition / CR Culvert resizing/replacement Restore stream buffers Mitigation Fund for restoration Stormwater /IC Recharge Stormwater Stormwater utility Adopt MS4 Rd Reduce or disconnect IC Instream Flow Reservoir Releases 10

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14 SWMI Pilot Process Apply SWMI framework to select communities/pws Range of conditions will be represented Staff will conduct pilots withinput input from community/pws and stakeholders Establish and streamline SWMI analysis toolsand data sources Results of pilots will inform and guide development of regulations Expected timeline: 6 to 9 months 14