Minimum Flows and Levels for the Peace River FLOW 2008 October, 2008 Marty Kelly

The Issues that Led to the Instream flows Process/Studies

Minimum Flows and Levels - Florida Statutes, Section 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 area The Policy Context

The Science Done

Flow Regime – Building Block Approach Benchmark Period Multiple MFLs - address seasonality Percent of Flow Reduction Technique Significant Harm - 15% reduction in available habitat Flow Regime gone Bad

Minimum Flows and Levels Components of an MFL (from Beecher 1990) 1.a goal – (e.g., non-degradation or, for the District’s purpose, protection from significant harm 2.identification of resources of interest to be protected 3.a unit of measure (e.g., flow in cfs, habitat in useable area, etc.) 4.a benchmark period, and 5.a protection standard statistic.

Two Benchmark Periods Blame 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." 15%

Low Flow Threshold - Wetted Perimeter Used for All Blocks

Low Flow Threshold - Fish Passage Used for All Blocks

Physical Habitat Simulation System Used for Blocks 1 and 2 Depth Velocity Substrate

Floodplain Snags Exposed Roots Long-Term Inundation Analysis Used for Blocks 2 and 3

The Preliminary Results Flow Prescription – Percent of Flow and Seasonality (middle Peace River at Arcadia)

Stationary vs. Dynamic Habitat Stationary Dynamic - Salinity

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 vegetation Establishment of an MFL requires identification of a critical biologically-relevant variable that can be defensibly and quantitatively related to variation in freshwater flows.

Analytical Tools “Modelers are people who like to play with numbers, but don’t have the personality to become engineers.” – Jimmy Carter

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

The Public Dialogue MFL Priority List and Schedule – Annual Update Proposed MFL – Report for Peer Review and Public Dissemination Public Meetings Waterbody Advocates and TAC’s and NEP’s Peer Review Report Staff Response (Recovery Strategy) $$$$$ Rule Development Rule Adoption The Role of the Governing Board

Recommendations for Others / Lessons Learned Legislative mandate has greatly facilitated process ad valorem taxing authority of WMDs Peer review process Recovery

Peace River by P. Metz - USGS Recovery Strategies

Questions Photo: Richard Gant – Silver River 2007 Florida photographic collection