Flood Damage Reduction

1. Flood Damage Reduction Module F4: Reformulation – Optimization, Incremental Analysis and Selection of the NED Plan

2. Student Learning Objectives The Student will be able to: • Use initial formulation information to develop/revise new formulation strategies • Describe the role of incremental analysis in plan formulation for flood damage reduction • Distinguish induced flooding from induced damages and know the importance of each to plan formulation

3. How do we help this town? High ground behind red line Town limits

4. Which do we choose? Detention pond? Channel Modification? Non-Structural Measures? High ground behind red line Town limits Levee/Wall?

5. Non-Structural $30M $40M $10M Pond $40M $20M -$20M Levees/Walls $60M $80M $20M Channel $100M $85M -$15M Initial Formulation (we have only just begun) Measure NED Cost NED Benefit Net NED Benefit

6. And we look at it all again • Fist or last positioning of measures • Dependencies • Combinability • Incremental Analysis

7. 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.”

8. Another Example - What’s An Increment? Levee alignment Reach 1 Levee tie-back options Reach 2 High ground behind red line Town limits Reach 3

9. Separable Increments of a Flood Damage Reduction Plan

10. Separable Increments – Did we miss an opportunity the first time?

11. 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

12. 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

13. Flood Plain Management Issues Where does the water go? • 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 11988 issue that must be disclosed in the documentation

14. Flood Protection Levee Lock Haven, PA Do you think this property could be affected?

15. 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)

16. Take Away Points • Incremental analysis is required to identify the NED Plan. • While a study may recommend a locally preferred plan, the NED Plan establishes the limit on the Federal investment.

17. Where We are Going • Next, we’ll start on Navigation • The first module will cover the authorities and policies related to the development of navigation projects.

18. Challenge Question: • How is the formulation criterion of acceptability incorporated into the formulation process? • How acceptable does the NED plan have to be? • Who does it have to be acceptable to?