A Federal Family Comes Together Association of State Floodplain Managers Conference

Transcription

1 A Federal Family Comes Together 2016 Association of State Floodplain Managers Conference

2 Region 6 by the Numbers 5 States 5 USGS Offices 6 USACE Districts 6 HUC2 Regions 40 HUC4 Subregions 403 HUC8 Watersheds 503 Counties 3,236 Communities 250,000 Flood Hazard Miles 2 565,927 Square Miles (Land Area)

3 The Challenge 250K miles of Flood Hazard Inventory 3

4 Multiple Agencies Multiple Efforts Federal Emergency Management Agency (FEMA) National Flood Insurance Program (NFIP) Flood Insurance Rate Maps (FIRMs) Levee Analysis and Mapping Procedures US Army Corp of Engineers (USACE) On-Going H&H Studies (planning, feasibility, watershed, etc) Corps Water Management System (CWMS) watershed modeling (2013) Levee Safety Action Classification (LSAC) US Geological Survey (USGS) Stream gage program Statistical hydrology and regional regression and watershed studies National Weather Service (NWS) Real-time forecasting and precipitation estimates Precipitation products 4

5 Multiple Agencies One Mission To provide reliable, impartial, timely information that is needed to understand the Nation s water resources. Deliver vital public and military engineering services; partnering in peace and war to strengthen our Nation s security, energize the economy and reduce risks from disasters. provide the best weather, water, and climate forecasts through international cooperation on hydro-meteorological observations, data exchange, modeling, research, and technology development; and to provide global leadership in setting meteorological standards and building partnerships to save lives and protect property. 5 Support our citizens and first responders to ensure that as a nation we work together to build, sustain and improve our capability to prepare for, protect against, respond to, recover from and mitigate all hazards

6 Interagency Flood Risk Management (InFRM) Team Objectives Generate basis for consistent hydrology across river basins throughout FEMA Region 6 Generate flow values using various hydrologic analysis techniques Examine and account for non-stationary trends Land use changes Climate variability Watershed Regulation & Flood Control Watershed report for coordination with locals and river basin authorities 0.2%, 1%, 2%, 4% and 10% exceedance probability events Modeling approach & tools to allow an increase in study granularity Increase interagency partnerships 6

7 Participating Agencies FEMA - Sponsor U.S. Army Corps of Engineers (USACE) Fort Worth District Tulsa District Galveston District Albuquerque District Little Rock District Vicksburg District U.S. Geological Survey (USGS) Texas Oklahoma Arkansas New Mexico Louisiana National Weather Service River Forecast Centers West Gulf Tulsa Lower Mississippi 7

8 Vision for Collaboration LiDAR Regression Hydrology Refined Hydraulics Modeling Base Level Engineering Model Refinement Update Hydrology based on CWMS Update Large Rivers based on CWMS assessment Large Physical Map Revisions for large scale river basin updates Follow on hydraulic assessments where warranted FEMA FIRM Updates Inventory Assessment Assess flood hazard inventory against most up to date information Continued refinement River Authority Input Basin-wide Hydrology Hydraulics Modeling based on best/readily available data USACE CWMS USACE/USGS Basin Assessment Coordinate with USGS and FEMA to determine appropriate basin refinements Climate variability Loss Rates Range of Flows 8 Coordinate with academia and local communities to review results Determine suggested loss rates, flow ranges, etc.. Local Reviews InFRM Watershed Report Release

9 USACE CWMS Models CIPR Consequence Assessment Studies Consequence-Based Top Screen Security Risk Assessments Dam Safety DSAC Risk Assessments EAP Maps IRRMP Levee Safety LSAC Risk Assessments EAP Maps Water Management Operating Plans Project Operation Inundation Maps What if Scenarios UOC/FRM Enhance Disaster Preparation Strengthen interagency Support Flood Risk Benefits Risk Transference Planning Planning Transformation Watershed based budgeting Watershed based analysis 9

10 What is CWMS? Corp Water Management Systems GIS Spatial information and H&H modeling prepared for basins where USACE has assets (reservoirs, levees, etc.) Intended use - coordination with USACE Operations Group during flood events (operation of gates, releases, etc.) HEC Modeling MetVUE (Event Simulation) HEC-HMS (Hydrology) ResSim (Storage) HEC-RAS (Hydraulics) HEC-FIA (Damages) 10 Data Acquisition Data Visualization (Hydrology) HMS FIA Model ing (Damages) (Storage) ResSim RAS (Hydraulics) Data Base Information Dissemination

11 CWMS is a National USACE Program 200+ watersheds identified for preparation $150M in analysis across program 11

12 CWMS for Collaboration CWMS efforts engage local communities and river authorities during data collection CWMS provides: a cursory look at hydrologic flow information across a river basin a basis for local, regional, state and Federal entities to engage in discussions related to changes in the watershed a basis for FEMA to review flow changes and effect on flood hazard inventory across a watershed a review of the current USACE operations manuals for reservoirs and other flood control structures a great starting point for refinement of flood hazard information available through 12CWMS

13 Taking CWMS one step further Statistical hydrology Rainfall-runoff modeling Existing conditions Future conditions Ultimate development conditions Period of record (POR) simulations Regulated Unregulated watershed conditions Reservoir studies Stochastic methods in hydrology Comparison and convergence of methods 13

14 Advantages Multi-Agency approach Advanced scientific team Leverage knowledge within each agency & all available information Strengthens Relationships between Federal Agencies Leverage newly developed USACE CWMS models Opens additional communications channels for additional collaboration Leverages funding from multiple programs Consistent results across watersheds Convergence of various hydrologic analysis techniques Look at impacts of non-stationary watershed trends on flood risk Provides data to address the FFRMS Executive Order and some TMAC recommendations Tools and models to increase granularity for detailed mapping 14 efforts

15 Why Watershed Scale Hydrology Assessment? Upper Trinity Watershed (Dallas-Fort Worth, TX) Flood control system Over $70 billion in damages prevented (60 years) $2-3 billion per year Water supply system 6.8 million served 15

16 Question How Much Uncertainty Do You Have with 100 years of Record? Dashed Yellow Line = Actual 100-yr (1%) Discharge Solid Yellow Line = Estimate of 100-yr (1%) Discharge based on previous years of record 100-yr (1%) Estimate varies from 100,000 to 450,000 cfs with 100 years of Record Credit: Beth Faber at USACE-HEC 16

17 Question How Much Gage Record Do You Need to Estimate the 100-yr Discharge? Dashed Yellow Line = Actual 100-yr (1%) Discharge Solid Yellow Line = Estimate of 100-yr (1%) Discharge based on previous years of record years of Record before 100-yr Estimate 17 Converges Credit: Beth Faber at USACE-HEC

18 Reasoning for Watershed Scale Investigations 100 years of Record may not be enough! Watershed models and stochastic techniques can help compensate for non-representative samples in the gage record Statistical hydrology is still a valuable tool to be used in this effort 149,000 cfs (2015 Gage 1%) 126,000 cfs (2013 Gage-1%) 18 23,000 cfs difference in 100-yr estimate after 1 Flood Event 40,000 cfs difference from BFE discharges

19 Products to aid Local Communities Watershed report Results from various hydrologic methods Selected results Tools, models, techniques and guidelines which can be used to increase granularity Comparison to previous flood risk studies within the watershed 19

20 First Steps: Guadalupe and Trinity Basins 20

21 Guadalupe Basin Hydrology Study 24 month schedule (completion September 2017) Using existing USACE Guadalupe CWMS HEC-HMS model, RiverWare model, and reservoir studies. USGS performing statistical analysis of stream gages NWS providing precipitation data Refinement of basin hydrology to support large scale PMR release for San Marcos River, Blanco River and Cypress Creek 21

22 Trinity Basin Hydrology Study 48 month schedule Using existing USACE Trinity CWMS HEC-HMS model, RiverWare model, and reservoir studies. USGS performing statistical analysis of stream gages and some HEC-HMS modeling NWS providing precipitation data Reservoir analysis for Richland Chambers Lake Local, Regional, State and Federal involvement and engagement, regular meetings held. 22

23 Closing Our technology centered around flood risk is good Our approaches can be improved Can benefit from local and regional engagement Leveraging technology, industry, owner/operator knowledge and academia May result in more technology advancement for determining flood risk More efficient use of federal tax dollars within the communities serviced Improved life safety & decreased property damages PLEASE STAY ENGAGED WITH US! 23

24 Questions? Gary Zimmerer, PE Mitigation Division, Deputy Director FEMA, Region 6 Gary.Zimmerer@fema.dhs.gov Jerry Cotter, PE Water Resources, Branch Chief USACE, Fort Worth District Jerry.L.Cotter@usace.army.mil 24