HAZARD MITIGATION IN HISTORIC DISTRICTS. Louisette L. Scott AICP, CFM Director, Dept. Planning & Development Mandeville, LA January 31, 2018

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1 1 HAZARD MITIGATION IN HISTORIC DISTRICTS Louisette L. Scott AICP, CFM Director, Dept. Planning & Development Mandeville, LA January 31, 2018

2 Mandeville, LA 2 Mandeville is Located on the northshore of Lake Pontchartrain across from New Orleans.

3 Bay Pontchartrain 3 Mandeville

4 active years right after the founding of Mandeville 6 hurricanes stronger than Cat. 3

5 Many of our historic homes were built elevated, especially in era after early hurricanes 5

6 Mandeville has a Historic context for elevated homes. note proportion: 2/3 1/3 6

7 7 Lake Pontchartrain Causeway 1956/1969 resulted in tremendous growth fastest growing community in the 80 s for~10 years

8 With opening of causeway. 8 Many new residents from New Orleans. New Orleans is protected by a levee system Mandeville gravity drainage Many folks did not realize the impacts/flooding from the Lake Occurred in late 50 s-70 s when post WWII homes were built slab on grade Many did not completely understand the environment they lived in.

9 9 A day in the life by the lake know your environment

10 NOAA - National Oceanic & Atmospheric Administration Hurricane Track ~100 years 10

11 11 Hurricane Katrina the new normal

12 Past just to east of Mandeville (NOLA) better situation for LA not for MS (SE wind) 12

13 13 Hurricane Isaac (2012)

14 Eye just to the west of Mandeville scenario causes more severe impact for storm surge. 14

15 Old Mandeville Shoreline Protection Study 15 Goal: Analyze previously identified flood risk management alternatives (projects) to allow for future planning

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18 Mandeville s Entire Historic District in SFHA Special Flood Hazard Area 18 SFHA: Special Flood Hazard Area FEMA defines the SFHA as the area where the National Flood Insurance Program s (NFIP) flooodplain management regulations must be enforced and the area where the mandatory purchase of flood insurance applies

19 Flood Maps - lingo 19 Zones AE and VE are: High Risk Coastal Areas In communities that participate in the NFIP, mandatory flood insurance purchase requirements apply to all of these zones FEMA defines as follows: Zone AE: Areas that have a 1% probability of flooding every year (also known as the "100- year floodplain"), and where predicted flood water elevations above mean sea level have been established. Properties in Zone AE are considered to be at high risk of flooding under the National Flood Insurance Program (NFIP). Zone VE: Coastal areas with a 1% or greater chance of flooding and an additional hazard associated with storm waves. Base flood elevations derived from detailed analyses are shown at selected intervals within these zones. BFE: The computed elevation to which floodwater is anticipated to rise during the base flood. Base Flood Elevations (BFEs) are shown on FloodInsurance Rate Maps (FIRMs) and on the flood profiles. The BFE is the regulatory requirement for the elevation or floodproofing of structures.

20 20 A pretty day on the lakefront

21 21 Overtopping the seawall (5.3 )

22 22 Flood Mitigation/elevation

23 23 Not just flood waters, but all that s in it.marsh grass, pigs, snakes

24 flood claims filed 2005 Katrina/Rita Storm Surge of 9.5 msl - $26,616,924

25 226 claims filed after Isaac Storm surge of 9.5 msl totaling $7,739,531 25

26 The financial value of mitigation 26 Katrina/Rita cost $26,616,924 Isaac cost $7,739,531 From Katrina in 2005, to Isaac in 2012, with same storm surge, number of claims was reduced almost in half and damage costs were reduced by 71%.

27 27 Hazard Mitigation Saves! January 11, 2018, the National Institute of Building Sciences found that, on average, every $1 spent on hazard mitigation measures, saves $6 in future disaster costs. For Flood Hazard mitigation $1 spent is $7 saved. According to NOAA the cumulative damage of 16 U.S. disaster events during 2017 is billion, which shatters the previous U.S. annual record cost of $214.8 billion (CPI adjusted), established in 2005 due to the impacts of Hurricanes Dennis, Katrina, Rita and Wilma

28 Reduces Cost of Down time for businesses 28

29 29 The other storm surge: HFIA Homeowner Flood Insurance Affordability Act NFIP Increases Began April 2016: 12%/YR FOR PRIMARY RESIDENTIAL $2500/YR MAX 25% increases for the following: Non-Primary residences (2 nd homes; vacation; rental) Business Buildings (income producing) Severe Repetitive Loss (SRL) NFIP is reauthorized every 5 years and is up for reauthorization this year. The House version has passed, now Senate has to pass their version, then will vote on final bill. Includes increases in pre-disaster mitigation funding Doubling of Increased Cost of Compliance (ICC) funding.

30 30 PRE-FLOOD MAP BUILDINGS POLICY RATES ARE INCREASING Many communities have a freeboard requirement, increasing BFE 2.

31 31 Insurance Premiums: VE zone rated at bottom of lowest horizontal member in this case, the slab. VE zone: $12,000 annual policy (to increase annually) $35,000 annual policy VE-zone

32 32 Commercial property Zone AE : significant increases ~ $10,000-$15,000 in four years. Rated at top of finished floor.

33 33 What happens if we don t mitigate?

34 34 How many do we lose? ~ 37 structures have been lost or demolished as a result of coastal flooding/storm damage

35 35 Lost historic structures/fabric

36 36 Mitigation Relocation

37 Entire Historic District in SFHA Special Flood Hazard area 37

38 Regulations and Requirements Variety of regulations for Flood Hazard Mitigation. ICC: International Building Codes NFIP: Regulates on the Insurance side of flood prone properties FEMA: Regulates Compliance within the SFHA, or flood prone properties ASCE 24: establishes engineering standards for construction in SFHA. Required on all FMA funded grant projects.

39 Funding Sources 39 PRE-DISASTER Private sources: CASH HOME EQUITY Grant funding: FEMA: FLOOD MITIGATION ASSISTANCE (FMA) HAZARD MITIGATION ASSISTANCE (HMA) Other: FEDERAL HOUSING ADMINISTRATION-FHA 203K LOAN/MORTGAGE

40 Funding Sources 40 POST DISASTER: Private: CASH INCREASED COST OF COMPLIANCE (ICC) = $30,000 from flood insurance policy Grants: FEMA HAZARD MITIGATION GRANT PROGRAM (HMGP) HUD-CDBG/DR - HOUSING AND URBAN DEVELOPMENT COMMUNITY DEVELOPMENT BLOCK GRANT-DISASTER RECOVERY SMALL BUSINESS ADMINISTRATION-SBA, SBA MAY FUND UP TO $200K ADDITIONAL FOR ELEVATION IF SUBSTANTIALLY DAMAGED

41 FEMA Bulletin for Historic Structures 41 -Explains how the NFIP defines historic structures and how it gives relief to historic structures from NFIP floodplain management requirements. -Provides guidance on mitigation measures that can be taken to minimize the devastating effects of flooding to historic structures. -The National Flood Insurance Program (NFIP) gives special consideration to the unique value of one of our Nation s most significant resources its historic buildings, landmarks, and sites. To be eligible for the variance, the structure has to be in a historic district and it has to be individually listed within the district. -If exemptions/variances are utilized, buildings still are at risk for flooding and increasing insurance premiums.

42 42 Historic Commercial property in VE-Zone Mandeville s founder Bernard de Marigny original home Premium ~$35,000 (max) in 4 years will business community abandon these structures?

43 Reception Hall 43 Below BFE, Base Flood Elevation. Not only risk of flooding but subject to increasing insurance rates.

44 Can these businesses survive? 44 Restaurant in historic building Candy shop

45 45 Historic home damaged, Again

46 Elevation and historic context 46 If we have to mitigate by elevation, what does it do to the historic context of our communities? Can we elevate and still maintain context? How can we help the property owner mitigate as well as preserve our community?

47 Zoning Issues 47 Does your community s zoning ordinance meet the challenges of elevation? Height? Is 35 your maximum height? Is there a formula or exception process for elevation? Setbacks? Front yard stair encroachment? (6 above grade) Additional height more adverse impact on sideyard setbacks. Elevated structures encroach into privacy (above fence line) Consider increasing yard setbacks Allow formula for height and allow structure to meet BFE without variances for height and setbacks.

48 Tool box Master Plan for historic area 48

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50 Design Considerations for Elevation of Historic Structures: 50 Minimize changes to parking and circulation that affect the historic setting. On-street parking Driveways side loaded with screening of vehicles Retain and Preserve building features/architectural details that contribute to the historic character of the building and streetscape. Use screening to mitigate underside of structure/storage and vehicles

51 51 Design considerations for Elevation of Historic Structures Create systems approach review for structure type Base zone detailing foundation How does it tie into original structure Pier and column design Screening of vehicles Previous existing driveway? Parking underneath structure? Does it change context from pedestrian scale to vehicular scale? Access stair entries/porches Proportion and scale How does it relate to existing structure? How does it relate to adjacent structures/neighborhood

52 52 Base zone detailing

53 Base detailing 53 Screening in wrong place Paint lattice a dark color to disappear Finish CMU block Screening corrected lattice painted dark CMU blocks finished

54 Base detailing - 54 Appropriate screening underneath Column and piers have correct scale and proportion and line up

55 Detailing: Commercial structure 55 Piers do not line up with columns Stairs not appropriate Zoning: Setbacks Parking in front Scale/proportion to street incorrect

56 56 Site vehicular access challenges front loaded, side or none (on street)?

57 57 Side loaded

58 58 Front Entry Stair

59 59 Elevations- Stair and Access

60 Elevation - Stair and Access 60

61 61 Stair and Access

62 62 Stair and access

63 63 Stair and access - commercial

64 64 In some areas, tax credits may be used to mitigate historic structures

65 Summary 65 Sea level is projected to rise. Know your risk. Evaluate how many non-compliant structures are located in the SFHA Insurance rates are rising NFIP reauthorization this year. Historic Structures are at risk affects local economy and character of community. Preservation community embrace mitigation and manage historic resources, not lose them. Work with local architects to review both elevation/mitigation projects and new construction Create historic properties in SFHA in the future Each property is unique don t try a broad brush approach Keep the historic context of your community intact

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