Risk-assessment baseline packet. County area 38085. Release 2026-10, data as of 2026-09-28.
Plan clock
Expired on 2022-02-28
- Plan
- Standing Rock Sioux Tribe/Sioux County, ND Hazard Mitigation Plan 2017 (FEMA plan 102636)
- Approved
- 2017-03-01
- Expires
- 2022-02-28
- As of
- 2026-09-28
- Days
- 1,673 days since expiry
- Update underway
- FEMA tracker shows a plan in progress
Generally not eligible for FEMA mitigation project grants (HMGP, FMA) until a new plan is approved, barring a 44 CFR 201.6(a)(3) exception. Planning grants are not affected.
Map group: Lapsed, not yet adopted or never covered.
What the packet contains
Sections in FEMA checklist order. Each heading names the review item its tables support; whether the item is satisfied is decided by the plan and its reviewers. Full tables are in the downloads above.
Supports B1-a Hazards
13 of the 18 National Risk Index hazards apply here; omission evidence is shown only where NRI rates a hazard "Not Applicable", no federal declaration names it and Storm Events has no record of it since 1996.
Highest expected annual loss (NRI, modeled): Cold Wave, Inland Flooding and Strong Wind.
Also check locally (not covered by NRI): dam failure (incl. upstream dams), levee failure, flash flood as its own subtype, ice jams, debris flows, erosion (riverine and coastal), land subsidence and sinkholes and expansive soils.
Check your state hazard mitigation plan's hazard list for this county; explain any hazard you drop.
Supports B1-b Location
- Avalanche, Coastal Flooding, Earthquake, Hurricane, Landslide, Tornado, Tsunami, Volcanic Activity and Wildfire: Census tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.
- Cold Wave, Drought, Hail, Heat Wave, Ice Storm, Lightning, Strong Wind and Winter Weather: Affects the whole planning area; national data do not distinguish locations within the county. Confirm locally.
- Inland Flooding: The FEMA Flood Insurance Rate Map (FIRM) is the required location source for flooding. See the FEMA Flood Map Service Center (https://msc.fema.gov) for this county.
Supports B1-c Extent
Storm Events records for 11 of 20 hazard groups, with the scale, observed range and worst recorded event for each; the others say local data required.
- Hail: 5 in hail, 2010-07-13
- Thunderstorm Wind: 109 kt (125 mph) estimated gust, Thunderstorm Wind, 2023-06-21, 1 direct injury
- Tornado: EF1 tornado, 2010-05-24, 0.73 mi within this county, 40 yd wide, $25,000 property; $0 crops (2010 dollars)
Supports B1-d Previous occurrences
22 federal declaration rows for this area (19 counted incidents), each with type, dates and county Public Assistance dollars.
New since the last plan (approved 2017-03-01): DR-4888-ND, DR-4613-ND, DR-4509-ND and EM-3477-ND.
2 statewide declarations listed separately.
Hazards with no recorded events are stated as such (6 of 18).
Storm Events history: 414 records (notable ones in the PDF, all of them in the Excel file).
Supports B1-e Probability
FEMA annualized frequency (modeled) for each hazard, with a descriptor from a scale defined in the packet.
- Highly likely: Hail, Lightning, Strong Wind and Winter Weather
- Likely: Cold Wave, Inland Flooding, Landslide, Tornado and Wildfire
- Possible: Drought, Heat Wave and Ice Storm
Historical frequency by intensity band (tornado, hail, wind): 9 bands from Storm Events.
Supports B1-f Variation across the planning area
Range of census tract risk scores within the area for 18 hazards (2 tracts; rated tracts only).
6 member jurisdictions: plan clock, repeat-flood count, Public Assistance dollars and event records naming the place (starter, confirm locally).
Supports B2-a, B2-b Assets and impacts
Local data required
County-level starter. The plan must describe impacts for each participant and its own assets.
Storm Events damage since 2017-03-01: $1,267,000 in county-coded records (51 records); $25,000 reported for the zone (67 zone records). Data through 2026-06-30; nominal dollars.
Checklist of what to gather locally: Critical facilities and lifelines per hazard; A problem statement per participant per hazard; Changes in development in hazard-prone areas since the last approval, or a statement of none (E1-a); Future assets.
Supports B2-a Context
Population 3,885; building value $879,299,588 and agriculture value $79,699,790 (total, not at risk).
National Risk Index rating Relatively Low; social vulnerability Very High; community resilience Very Low.
Supports B2-c Repetitive loss
Repetitive-loss properties, FMA definition (44 CFR 77.2): 0 repetitive loss, 0 severe repetitive loss. NFIP insurance definition: 0 and 0.
Mitigated 0; insured 0; NFIP data as of 2026-08-02. Counts by occupancy and for each member community are in the packet.