NAVAJO NATION PROFILE

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2 NAVAJO NATION PROFILE Largest land based area and federally recognized tribe in the United States Over 27,000 square miles (or 17.2 million acres with a population of over 300,000 people. Covers Arizona, New Mexico, and Utah Navajo Nation is larger than 11 of the 50 states: West VA, Maryland, Hawaii, Massachusetts, Vermont, New Hampshire, New Jersey, Connecticut, Delaware, Rhode Island, and Washington DC. Land Status: Trust Land (90%), Allotted Land and Fee Simple Land 110 Chapters/communities 24 Council Delegates- reduced from 88 in 2011 Navajo Housing Authority (NHA) is the largest Tribally Designated Housing Authority (TDHA) in the United States NHA managers over 9,000 homes

3 27,000 square miles or 17.2 million Acres 110 Local Government Chapter Communities 304,000 Estimated population

4 VISION AND MISSION STATEMENT VISION STATEMENT Housing Our Nation By Growing Sustainable Communities. MISSION STATEMENT Hooghandei haa hozhoogoo iinaa silaa do a nooseelth (Center of Family Growth, Strength and Beauty). We are committed to building sustainable quality homes, promoting economic self-sufficiency and providing exemplary services through professionalism, leadership and respect.

5 BUSINESS OF NHA Tribal enterprise outside the Navajo Nation Government NHA Website: Homes Home ownership and lease units Housing Projects: New Developments, Modernizations, and Scatter Sites. Self-insured Home Developer and Floodplain Manager Repair homes due to floods, fires, etc. Sustainable Development

6 NHA S NEEDS HUD requirement to develop outside flood hazards Problem: No flood hazards identified in Navajo Nation Solution: Identify flood hazards for proper NHA planning and development of homes Identification of flood hazards has existed on the Navajo Nation for decades

7 WHY FLOOD HAZARD MITIGATION? Flood Hazards generally unknown on most tribal lands Danger to life and property Need to identify hazards

8 HAZARD MITIGATION PLANNING Goal : Make communities hazard and disaster resistant Use history and flood map information to better plan future development Develop a mindset of managing risk

9 FLOODING ON NAVAJO NATION

10 FLOODING ON NAVAJO NATION

11 NHA BASE MAPPING Coordinate Systems Problem: 5 State Plane coordinate systems, 2 UTM systems Solution: Unique Coordinate System: Stereographic Double Covers Entire Navajo Nation Meets Federal Geographic Data Committee (FGDC) & Federal Geodetic Control Committee (FGCC) Standards Single Navajo Nation Geospatial Database

12 STATE PLANE & UTM ZONES IN NAVAJO NATION

13 NHA BASE MAPPING Base Mapping Ground Control Survey Digital Aerial Photography (B/W, Color, CIR) Analytical Triangulation Control Extension Digital Elevation Model (DEM) Generation Digital Orthophotography Generation

14 GEODETIC GROUND CONTROL 77 Control Points Acquired

15 GROUND CONTROL SURVEY

16 NHA STEREOGRAPHIC DOUBLE PROJECTION Map Projection Final adjusted coordinates and elevations were tabulated and delivered. Both geodetic coordinates (latitude and longitude) on the GRS80 ellipsoid and projected coordinates were provided. The projected coordinate values can be provided in any projection desired by the client including U.S. State Plane and/or UTM. The custom, double stereographic based projection is to encompass the Navajo Nation project area. This projection was designed to minimize the departure of the combined scale factor from unity over the study area. More information on the derivation and benefits of this projection are available at the Navajo Housing Authority s Land Surveying Department office in Ft. Defiance, Arizona.

17 NHA BASE MAPPING Collected seamless and accurate base map for the entire Navajo Nation (AeroMetric and Towill) Ground Control Survey Analytical Triangulation Control Extension Digital Orthophotography (B/W, Color, CIR) Digital Elevation Model (DEM) Generation

18 FLOODPLAIN PROJECT- PHASE 1 URS completed 260 miles of floodplain studies (March 2012) Approximate Model- Backed floodplains Maps include approximate water surface elevations Hydrology: 2008 USGS regression and gage data Hydraulics: HEC-RAS modeling Developed flood maps, report, and GIS database

19 FLOODPLAIN PROJECT- PHASE 2 2,800 miles of stream studied: HUC-12 watersheds

20 FLOODPLAIN PROJECT PHASE 2 Beyond Floodplain boundaries 1% annual chance depth grids maps Hazard Mitigation Plan (Flood & Fire) Implemented a hazard mitigation strategy that upholds NHA s mission statement Sustainable Development

21 DEPTH GRID MAPS Derived from subtracting ground elevation from the 1% Annual Chance flood depth Communicates flood risk by flood depth

22 FLOODPLAIN PROJECT PHASE 3 2,000 miles of stream to be studied: HUC-12 watersheds

23 3D PERSPECTIVE 3D Perspective provides site suitability for future construction of homes and utilities Mitten Rock

24 3D VIDEO

25 PROPOSED FLOODPLAIN MANAGEMENT POLICY 2 Prong Approach - guides development away from flood hazards and mitigate homes already in the floodplain 1. Freeboard Policy 2. Horizontal Set-Back Policy Build quality homes in a safe location to safeguard the life and property of the Navajo Nation

26 FREEBOARD POLICY Point A Point B Using ArcView locate two points on the Floodplain_Boundaries.shp file adjacent to the site. One point upstream and one point downstream of the housing site. Determine the coordinates of these points. Point A: E, N Point B: E, N

27 FREEBOARD POLICY Determine Point A land ward and 2-ft higher than Point A. X X Point A In the field, locate the Edge of Floodplain; GPS Point A and Point B using coordinates determined in the office.

28 FREEBOARD POLICY 2-ft Freeboard X X Point A Point A

29 FREEBOARD POLICY Determine Point B land ward and 2-ft higher than Point B. X X Point B Point B

30 FREEBOARD POLICY 2-ft Freeboard X X Point B Point B

31 HORIZONTAL SET-BACK POLICY

32 PROPOSED FLOODPLAIN MANAGEMENT POLICY Freeboard Policy Provide factor of safety in very flat terrain Horizontal Set-Back Policy Set-back distance based on discharge and erosion factor Discharge unique for each flooding source Select policy that provides greatest factor of safety to be implemented in specific context

33 FIRE HAZARD MITIGATION Develop away from high and extreme fire hazards NHA is self-insured Build quality homes in a safe location to safeguard the life and property of the Navajo Nation

34 FIRE HAZARD MITIGATION Defining Fire Risk - influenced by: Density of vegetation/fuel load categories: High Fuel Load forest cover Medium Fuel Load shrub cover Low Fuel Load grass cover

35 FIRE HAZARD MITIGATION Defining Fire Risk also influenced by: Slope of land: High slope 20 percent grade or more Medium slope 6 to 19 percent grade Low slope 0 to 5 percent grade

36 FIRE HAZARD MITIGATION Fire Risk Categories Low Slope (0-5%) Medium Slope (6-19%) High Slope (20% and up) Low Fuel Load (grass) Moderate Moderate Moderate Medium Fuel Load (shrub) Moderate High Extreme High Fuel Load (forest) High Extreme Extreme

37 FIRE HAZARD MITIGATION

38 FLOODPLAIN PROJECT PHASE 1-2 Evaluation of Structures & Infrastructure inside Floodplain Phase 1: 69 Structures inside Floodplain Phase 2: To date, 326 Structures inside Floodplain Phase 1-3: 665 Structures projected to be inside Floodplain [Over 9,000 NHA homes in Navajo Nation] Critical Need for Flood Hazard Mitigation

39 FLOODPLAIN PROJECT PHASE 3 Drainage Design Manual Fire Mapping Implementation of Hazard Mitigation projects 2,000 miles of floodplain studies Phase 1 3 total over 5,000 miles of floodplain studies Depth Grid Maps Hazard Mitigation Plan (Flood & Fire) - continuation Project website nhafloodplainstudy.com

40 ARCGIS ONLINE PROJECT WEBSITE- DEMO

41 SUMMARY NHA has taken important steps in flood and fire hazard mitigation: 1. Accurate and up-to-date base map 2. Identification of flood and fire hazards using the latest technologies 3. HMP identifies best practices for planning and mitigation NHA effectively identifying and mitigating flood and fire hazards This will lead to sustainable and safe development NHA implementing floodplain management policy This will safeguard NHA homes from future hazards and develop resilient communities

42 THANK YOU!