Structural - Reservoirs McCook, Ill. Mt. Morris Dam Center Hill Lake, Tenn. Yatesville Lake, Ky.
Structural - Walls & Levees Lock Haven, PA Frankfort, KY West Columbus
Channel Modification Projects Harlan, KY, tunnels Minnesota River, MN, diversion Martins Fork, KY, diversion River Rouge, MI, channelization
Beach Nourishment, (Before) Miami/Dade County, FL Beach Nourishment, (After) Miami/Dade County, FL
NATIONAL FLOOD PROOFING COMMITTEE US Army Corps of Engineers Flood Proofing National Nonstructural/ Flood Proofing Committee
Nonstructural FRM Measures o Elevation o Relocation o Floodwalls, Levees and Berms o Buyout/Acquisition o Dry Flood Proofing o Wet Flood Proofing o Flooding Warning/Preparedness
Elevating on Extended Foundation Walls
Elevating on Fill
Elevation on Piers, Posts, Piles, or Columns Piers Piles Columns Posts
Relocation Process Moving the Structure o oEvacuate temporary roadway o oAttach structure to trailer o oTransport structure to new site
Restoration of Old Site Relocation Process Restoration of Old Site o oPlan must include a new use for the evacuated floodplain o oDemolish and remove foundation and pavement o oDisconnect and remove all utilities o oGrading and site stabilization
Evacuated floodplain area
Ring wall/levee - closure
Waterproof Sealant Dry Flood Proofing: Methods
Dry Flood Proofing Method: Waterproof Sealant
Elevate Utilities Wet Flood Proofing
Louvre Let Water In
Flood Warning/Preparedness Components o Flood Threat Recognition System o Warning Dissemination o Emergency Response o Post-Flood Recovery o Continued Plan Management
- Detailed evacuation plans and inundation mapping - Stream gages with/without remote sensing - Rain gages with remote sensing Flood Warning & Emergency Evacuation Plans (FWEEP) Nonstructural FDR Solutions FWEEP’s are almost always cost effective and relatively inexpensive
National Flood Insurance Program 44CFR o Flood Plain Regulation (FDR) o Flood Insurance (Risk Sharing) o Flood Mitigation (FDR)
STREAM CHANNEL FEMA Definition: 100 Year Floodplain FLOODWAYFLOOD FRINGE ______________________________ 100 year flood _____ Base Flood
Structural and Nonstructural Measures Structural measures keep the floods away from resources in the floodplain Nonstructural measures keep the resources away from floods in the floodplain
Basic Formulation Strategy The basic formulation strategy is to formulate to meet each of your planning objectives without violating any constraints. Every iteration of the formulation step must employ this basic strategy.
How - Formulation Strategies All possible combinations Measures strategy Convergent thinking Divergent thinking
o New Uses of the Evacuated Flood Plain o Ecosystem Restoration o Recreation o Spillover Benefits o Water Quality Improvement o E.O o NFIP Regulations o Mitigation of Adverse Effects of Structural Projects Nonstructural Opportunities
How do we help this situation? High ground behind red line Town limits
What measures would help? High ground behind red line Levee/Wall? Detention pond? Town limits Channel Modification? Non- Structural Measures?
Evaluation of Existing
Future Without Conditions
Reservoir / Detention Storage
FDA Model Evaluates Measures Mathematical models are used to evaluate the impacts of alternatives for flood damage reduction The Corps’ Flood Damage Assessment (FDA) model of expected annual damage estimation is the preferred method of modeling the effects of formulated plans Developed and Maintained at HEC – Specific training is available on the FDA model
Formulation With FDA Model Walls, levees Floodproofing Channels Clearing & snagging Dams Detention reservoirs
EAD Calculation for with project condition
Where do we begin in formulation? High ground behind red line Levee/Wall? Detention pond? Town limits Channel Modification? Non- Structural Measures?
First or Last? High ground behind red line Levee Detention pond
Dependencies Flood damage reduction plans often comprise several measures Some measures may require implementation of other measures in order to function properly: Interior drainage measures (pump stations and/or ponding areas) with levees/floodwalls Warning system, operations manual, or FWEEP when plans have closure structures requiring human intervention (put the sand bag in the slot, flip the switch on the gate motor power control, etc.)
Combinability Flood damage reduction plans often comprise several increments More often flood damage reduction plans have measures that can be combined in many ways, shapes, and sizes to achieve NED
-$15M$85M$100MChannel $20M$80M$60MLevees/Walls -$20M$20M$40MPond $10M$40M$30M Non- Structural Measure NED Cost NED Benefit Net NED Benefit Initial Formulation (we have only just begun)
And we look at it all again - Reformulation First or last positioning of measures Dependencies Combinability Incremental Analysis
Increment Defined An increment is any part of a plan that can be eliminated without jeopardizing the proper function of the remaining parts of the plan. Thus, different levels of project performance are not increments. WRDA 1986 Definition of Separable Element. “For purposes of this Act, the term "separable element" means a portion of a project-- (1) which is physically separable from other portions of the project; and (2) which-- (A) achieves hydrologic effects, or (B) produces physical or economic benefits, which are separately identifiable from those produced by other portions of the project.”
Another Example - What’s An Increment? High ground behind red line Reach 1 Reach 2 Reach 3 Levee alignment Levee tie-back options Town limits
Separable Increments of a Flood Damage Reduction Plan Plan IncrementNED Costs NED Benefits Net NED Benefits Levee A (1)$21M$20M-$1M Levee B (1&2)$40M$70M$30M Levee C (1,2 &3)$60M$80M$20M
Separable Increments – Did we miss an opportunity the first time? Plan IncrementNED Costs NED Benefits Net NED Benefits Levee D (2)$21M$50M$29M Levee E (3)$20M$10M-$10M Levee F (2 &3)$39M$60M$21M
Identifying the NED Plan Without-project damages With project damages Benefits are damages reduced Net benefits are benefits less project costs (total life cycle costs, including environmental mitigation) Compare across project scales and between alternatives to determine plan that yields greatest NED benefits Decision-makers always have the final say
Environmental Consequences Flooding is natural; flood damage reduction is not Flood damage reduction measures can have environmental consequences Some are intended, some are not Some are anticipated, some are not Some are beneficial, some are adverse Unanticipated, unintended consequences may be the worst type
Flood Plain Management Issues Induced flooding is not the NED issue Induced damages are the issue Avoiding or mitigating for induced damages are part of project costs and must be considered in plan formulation Induced flooding is an NFIP/EO issue that must be disclosed in the documentation Where does the water go?
Flood Protection Levee Lock Haven, PA Do you think this property could be affected?
FEMA and NED Formulation Issues National Flood Insurance Program participation assumed FEMA coordination essential and a matter of policy FEMA buyout land restrictions on Corps measures Locally desired protection (especially 100-year)
Sponsors’ Old Role Prior to 1986: l Not as politically active l Uninvolved in project development l No cost sharing other than LERRD’s
Sponsors’ Changing Roles Today’s Sponsors are: l Very politically active l In many cases technically capable of accomplishing work without COE support l Actively involved in project development l Demanding faster, better, cheaper l Want special application of policies for their projects.
Sponsors Political Activities — Actively building state and local coalitions — Campaigning for tight state revenues — Working closely with Congressional Delegations — Actively participating in national associations — Engaging ASA(CW) — Actively building state and local coalitions — Campaigning for tight state revenues — Working closely with Congressional Delegations — Actively participating in national associations — Engaging ASA(CW)
Greater Involvement in Project Development - Integral member of study team - Performing more in-kind services - Meeting often with Corps team - In on major study changes - Will call and visit HQ quickly
Greater Involvement in Project Development Congress provided sponsors authorities to conduct planning, design and construction of project. l Section 203 WRDA 86 - study deep draft navigation l Section 204 WRDA 86 - design and construct deep draft navigation l Section 303 WRDA 90 - construct small navigation projects l Section 206 WRDA 92 - construct shoreline protection projects l Section 211 WRDA 96 - construct flood control project l Section 2003 WRDA 07 – credits for materials and services provided for design and/or construction
Demanding Faster, Better, Cheaper Section 203 WRDA 96 –If feasibility study cost increases greatly after the FCSA has been signed, the sponsor’s incremental share can be delayed until after project construction or 5 years after the Chief of Engineers’ report is issued. Reconnaissance Studies
Equal Treatment - Regional consistent analysis - Equal application of policies - In-kind credit — Crediting for construction related activities now allowed under Section 2003 of WRDA 2007!!
Take Away Points Plan formulation is the art of creating plans to address the objectives and constraints related to flood damage reduction problems and opportunities In developing plan formulation strategies, you need to understand the basic policies affecting plans for flood damage reduction improvements. Breakpoints in costs are especially important to formulation and associated costs need to be included in the analysis While a study may recommend a locally preferred plan, the NED Plan establishes the limit on the Federal investment.