Minimum Flows and Levels for the Peace River

FLOW 2008 October, 2008Marty Kelly http://www.swfwmd.state.fl.us/projects/mfl/

The Issues that Led to the Instream flows Process/Studies

Minimum Flows and Levels - Florida Statutes, Section 373.042 -

The minimum flow for a given watercourse shall be the limit at which further withdrawals would be significantly harmful to the water resources or ecology of the areaThe Policy Context

The Science Done

Flow Regime Building Block ApproachBenchmark Period Multiple MFLs - address seasonalityPercent of Flow Reduction TechniqueSignificant Harm - 15% reduction in available habitatFlow Regime gone Bad

Minimum Flows and Levels

Components of an MFL (from Beecher 1990)a goal (e.g., non-degradation or, for the Districts purpose, protection from significant harmidentification of resources of interest to be protecteda unit of measure (e.g., flow in cfs, habitat in useable area, etc.)a benchmark period, anda protection standard statistic.

Two Benchmark PeriodsBlame it on Hal

In their peer review report on the Upper Peace River, Gore et al. (2002) stated, in general, instream flow analysts consider a loss of more than 15% habitat, as compared to undisturbed or current conditions, to be a significant impact on that population or assemblage."

Low Flow Threshold - Wetted PerimeterUsed for All Blocks

Low Flow Threshold - Fish PassageUsed for All Blocks

Physical Habitat Simulation SystemUsed for Blocks 1 and 2 Depth Velocity Substrate

FloodplainSnagsExposed RootsLong-Term Inundation AnalysisUsed for Blocks 2 and 3

The PreliminaryResultsFlow Prescription Percent of Flow and Seasonality (middle Peace River at Arcadia)

Stationary vs. Dynamic Habitat

The volume of water in the system less than a given salinity e.g. available fish habitat in given salinity zone

The bottom area in the system less than a given salinity e.g. benthic invertebrate habitat

The shoreline length in the system less than a given salinity e.g. amount of shoreline vegetationEstablishment of an MFL requires identification of a critical biologically-relevant variable that can be defensibly and quantitatively related to variation in freshwater flows.

Analytical ToolsModelers are people who like to play with numbers, but dont have the personality to become engineers. Jimmy Carter

LFT = 90 cfsBased on Combined Flows of Horse, Joshua and Arcadia Gages

The Public DialogueMFL Priority List and Schedule Annual UpdateProposed MFL Report for Peer Review and Public DisseminationPublic Meetings Waterbody Advocates and TACs and NEPsPeer Review ReportStaff Response(Recovery Strategy) $$$$$Rule DevelopmentRule AdoptionThe Role of the Governing Board

Recommendations for Others /Lessons LearnedLegislative mandate has greatly facilitated processad valorem taxing authority of WMDsPeer review processRecovery

Peace River by P. Metz - USGSRecovery Strategies

QuestionsPhoto: Richard Gant Silver River 2007Florida photographic collection