committed to our coast

Report Summary

March 2014

Senate Concurrent Resolution 39 of the 2013 Regular Legislative Session – Phase I Study

The Current Landscape

28

131

110

6

1

Levee/Flood Districts

49

Drainage Districts

Water Districts

State

Reservoir Districts

Conservation Districts

Background on SCR 39

• Authored by Senator Morrish

• Passed unanimously by Louisiana Legislature in May 2013

• Directs CPRA and DOTD to conduct a science-based study to better understand the adequacy of the current alignment of our Louisiana levee districts, drainage districts, conservation districts, and other water resource districts

• The goal is to improve and update the territorial jurisdictions of the various entities responsible for flood protection, storm water management, drainage, and water resource management and to efficiently and effectively meet the needs and safety of Louisiana’s citizens for future decades

SCR 39 Study Team

Phase I Tasks

• Gather baseline data

• Review relevant statutes

• Consult with districts through survey instrument

• Analyze existing alignments

• Develop science based scenarios

• Prepare report

Data Sources• Louisiana Department of

Natural Resources• Louisiana Legislative

Auditor reports• Louisiana Division of

Administration’s Boards and Commissions database

• Association of Levee Boards of Louisiana (ALBL)

• U.S. Census Bureau• Survey instrument

Key Findings - Data Analysis• 65 levee and water districts created by state with wide range of

responsibilities

• Operational budgets, revenues, and revenue generation mechanisms vary widely

• Staffing levels vary widely

• Spending, O&M budgets, and responsibilities differ from district-to-district

• Available funding varies in accordance with source of revenues

• Many adjacent levee districts re responsible for managing connected parts of same flood protection system

• Many dams exist outside of any surface water control jurisdiction

• Many district boundaries do not follow watershed boundaries

Challenges Posed by Current Alignment

• Fragmented management of interconnected infrastructure

• Operation of dams by non-flood control entities• Disparate funding

Development of Science-Based Alternatives

• Statewide department of water resources or regional districts, DOTD districts, and No Action scenario– Do not provide science-based solutions

• FEMA flood hazard mapping– Considered an insufficient dataset due to multiple

disputed or incomplete maps• Watershed approach• Hazard-based approach (address source of

threat and include hydraulic modifications)

Watershed Approach• Examined the current industry standard methodologies,

which all point to a watershed-based approach– USACE, EPA, NRCS, USGS all utilize this methodology

– Most federally delineated watersheds are based upon USGS divisions

• Six levels of hydrologic unit delineation:– The lower the Hydrologic Unit Code (HUC), the greater the

aggregation of sub basins and the fewer watersheds overall

– For instance, HUC 2 has divided up the state of Louisiana into only 4 basins; meanwhile HUC 12 has divided the state into 1,273 basins

Watershed Approach: USGS Hydrological Unit Codes (HUCs) Watersheds

Hazard-Based Approach• Hazard-based alternative

developed after consultation with stakeholders

• Mississippi River and Tributaries Project informed initial development of alignment for riverine threats

Hazard-Based Approach

• For hurricane storm surge threat, used northern boundary of 100-year storm extent

• Threat only in southern portions of state

• Data includes manmade hydraulic barriers such as levees and floodgates

Evaluation of Initial Approaches

• None of the watershed or hazard-based alternatives were suitable as stand-alone solutions

• USGS HUC 4 and HUC 6 provide a foundation for combining a watershed approach with hazard-based considerations

• Three hybrid alignments were then developed to incorporate best aspects of watershed and hazard-based approaches

Flooding Hazard-Based Alternative 1 (FHBA 1)• Consists of 9 watersheds• Similar hazard management actions in each district,

and in adjacent districts• Based on natural hydrologic patterns while

accounting for manmade infrastructure• Minimally bisects urban areas• Streamlines emergency management actions• No districts with 0 population• Poorly distributes population in eastern LA

Flooding Hazard-Based Alternative 2 (FHBA 2)• Consists of 14 areas

• Similar hazard management actions in each district, as well as in adjacent districts

• Based on natural hydrologic patterns while accounting for manmade infrastructure

• Few urban centers in several coastal areas

• Surge boundary also captures major topography interface from costal plain to upland areas

Flooding Hazard-Based Alternative 3 (FHBA 3)• Consists of 10 areas

• Similar hazard management actions in each district, and in adjacent districts

• Captures surge vs. riverine considerations for most districts

• Few urban centers in several coastal areas

• Evenly distributes population

• Reflects the natural differences in topography in drainage patterns created by the Bonnet Carre Spillway, which segments the Pontchartrain Basin into upper and lower portions

– This is captured in all USGS HUC delineations except for HUC 2

Evaluation of Hybrid Alignments• The three hybrid alignments are potentially viable from a

science-based standpoint– All take into account a watershed-based approach– All also consider existing water management infrastructure and

actions• Alignments also reflect major basins where water

management actions are similar and focused• Enables coordinated management of hydraulic

structures and planned risk reduction measures• Potential to reduce fragmented management of

infrastructure• Compatible with goals and objectives of 2012 Coastal

Master Plan

Next Steps• Additional exploration of these potentially viable options

is necessary prior to development of any final recommendations

• Conduct second phase of study to gather additional data:– Revenue– Asset and infrastructure valuations– Indebtedness and bond issues– Major construction projects underway or planned– Outstanding litigation

• Prepare Phase II report with recommendations for consideration by the Legislature including implementation actions with timelines, if appropriate

Questions?

Extras

Baseline Data: Levee Districts• 26 levee districts currently active

• 20 responded to survey

• Includes individual members of SLFPA East (East Jefferson, Lake Borgne, Orleans) and SLFPA West (Algiers, West Jefferson)

• Includes Chenier Plain and Iberia Parish authorities, although neither has passed tax referenda yet

• Includes Bunches Bend, although the jurisdictional relationship between Bunches Bend and 5th LA Levee District is ambiguous

*Note: Local entities such as Baton Rouge Department of Public Works, St. Tammany Drainage District, Ascension Drainage District, and Angola Penitentiary that are not established by state statute but whose span of control and mission involve significant water control activities are not included in these values.

Baseline Data: Water Districts• 40+ water districts currently active

• 14 responded to survey

• Includes several entities established by state statute but where programmatic authority over surface water control is unclear such as the Stream Control Commission, Natural and Scenic Rivers System, and Wildlife and Fisheries Commission

• The project team was unable to identify data or information for 15 districts

• In those instances where districts did not respond to the survey request, the project team supplemented existing data with information from publicly-available data sources such as the Louisiana Legislative Auditor

• Both the Sabine River Authority and Amite River Basin Drainage and Water Conservation District reported major flood control activities

Baseline Data: Water Districts• Exact number of active surface water control districts was

difficult to ascertain because data was not available for many (only 14 water control districts responded to survey)

• Some statewide surface water control entities such as the Stream Control Commission are not pictured

Problem Definition: Summary of Key Findings

Orange circles identify areas where protection crosses (or will cross) jurisdictional boundaries

Problem Definition: Summary of Key Findings

Many dams lay outside any surface water jurisdiction, yet have inherent flood control aspects

Screening of Alternatives Summary

Alignment SCR 39 No. of entities

Considers watershed

Captures storm surge

hazard

Accounts for existing

infrastructure

Reduces no. of

entities

Reduces fragmented

infrastructure

Could reduce coordination challenges

Can account for dams

Enables regional

watershed approach

Bisects urban areas

Difficulties generating

revenue

Incongruent geometry

No Action 28-65 x x x

Single State Entity 1 x x x x x

DOTD DIstricts 9 x

USGS HUC 2 Watersheds

X 4 x x x

No, because too few

districts, would require further

division

x x x

USGS HUC 4 Watersheds

X 12 x x x x x x x

USGS HUC 6 Watersheds

X 21 x x marginally marginally x marginally x x x

USGS HUC 8 Watersheds

X 59 x x x x x x

USGS HUC 10 Watersheds X 275 x x x x x

USGS HUC 12 Watersheds X 1273 x x x x x

FHBA 1 X 9 x marginally x x x x x x

FHBA 2 X 14 x best x x x x x x x

FHBA 3 X 10 x well x x x x x x