Natural Hazards and Climate Exposure: desk report

The rule

Code computed the rating from the assessor's inputs:

impact_likely=yes -> 2

Set by the rule

Decision

Released with flags

The engine's reasons

• Agencies not in the register or the evidence: Carroll County Engineer, FEMA
• Independent assessments split on the category (5 samples: {'2': 4, '1': 1})

Evidence state

REPORTED · desktop, consultant or developer record

The assessor's comments

Landowners report floodplain fields flood for a day or two most springs, and Sallow Creek overtopped Linnet Road at the county bridge in the June 2019 flash flood. Seasonal high groundwater may be near the surface in the floodplain. Design wind is 115 mph and snow load 20 psf. No hail or wildfire screen is in the data room.

Worst case

The same rule on the worst case gives no rating above the point.

• Present: yes

  Local flood history beyond FEMA mapping is documented: landowners report floodplain fields flood for a day or two most springs (C-9f6b8123d8) and Sallow Creek overtopped Linnet Road in the June 2019 flash flood (C-db721b9fe7). Seasonal high groundwater may be near the surface in the floodplain (C-05146fd25c). Hail, wildfire and heat are not addressed. The seismic-low finding (C-560f40e113) belongs to EN-02 and does not offset this.

  Cites C-9f6b8123d8, C-db721b9fe7, C-05146fd25c, C-560f40e113

• Extent: peripheral

  Flooding and shallow groundwater are tied to the Sallow Creek floodplain, part of the site; about 14 flood-fringe acres are flagged as possibly dropped (C-75d2a2cad3). Design loads of 115 mph wind and 20 psf snow are standard (C-4f11de30a3).

  Cites C-9f6b8123d8, C-75d2a2cad3, C-05146fd25c, C-4f11de30a3

• Avoidable: yes

  Siting outside the floodplain, dropping the 14 flood-fringe acres if a local hydraulic model shows higher levels (C-75d2a2cad3), and elevated equipment and drainage design answer the documented flood exposure.

  Cites C-75d2a2cad3, C-9f6b8123d8

• Pathway: standard

  No hazard approval is documented. Building code loads and drainage review near the floodplain apply at routine terms; construction stormwater coverage is separate (C-4bf6e9a178). Basins are below dam permit size (C-ebc49abde3).

  Cites C-75d2a2cad3, C-4bf6e9a178, C-ebc49abde3

• Impact likely: yes

  Recurring spring flooding, a flash flood that overtopped the county bridge on Linnet Road, and near-surface seasonal groundwater make a physical or design effect likely if array rows or access routes lie in or near the floodplain (C-9f6b8123d8, C-db721b9fe7, C-05146fd25c, C-75d2a2cad3).

  Cites C-9f6b8123d8, C-db721b9fe7, C-05146fd25c, C-75d2a2cad3

Supporting statements (8)

Each claim the row cites: the statement in the assessor's words, then the quote the engine found on the page.

1. C-05146fd25c

   Free water was met at 6 to 14 feet in 9 borings, mostly perched near Sallow Creek; seasonal high groundwater may be near the surface in the floodplain.

   Seasonal high groundwater may be near the surface in the floodplain.

   Preliminary Geotechnical Engineering Report - Tamsin Ridge Solar and Storage Project · DR-0018 · Page 1 · 2023-05-15

   Source field_study · Claim type presence · Polarity presence · Confidence medium · Quote check exact, 100 of 100

   Cited by EG-01 · Filed under EG-01, EN-08

   See it on page 1, claim C-05146fd25c

2. C-4bf6e9a178

   Disturbance over one acre requires Ohio EPA construction stormwater general permit OHC000006 coverage, including an SWP3 and Notice of Intent.

   Construction will disturb more than one acre, so the Project needs coverage under Ohio EPA's construction

   Stormwater, Floodplain and Drainage Memo - Tamsin Ridge Solar and Storage Project · DR-0019 · Page 1 · 2023-06-05

   Source consultant_memo · Claim type regulatory · Polarity presence · Confidence high · Quote check exact, 100 of 100

   Cited by EG-02, PE-02 · Filed under EG-02, PE-02

   See it on page 1, claim C-4bf6e9a178

3. C-4f11de30a3

   Design loads: basic wind speed 115 mph, ground snow load 20 psf, and 0.5-inch radial ice for gen-tie structures.

   basic wind speed 115 mph (Risk Category II), ground snow load 20 psf, and 0.5-inch radial ice for the gen-tie structures.

   Preliminary Geotechnical Engineering Report - Tamsin Ridge Solar and Storage Project · DR-0018 · Page 1 · 2023-05-15

   Source consultant_memo · Claim type study_finding · Polarity neutral · Confidence medium · Quote check exact, 100 of 100

   See it on page 1, claim C-4f11de30a3

4. C-560f40e113

   Seismic site class C; seismic hazard is low.

   Seismic site class C; seismic hazard is low.

   Preliminary Geotechnical Engineering Report - Tamsin Ridge Solar and Storage Project · DR-0018 · Page 1 · 2023-05-15

   Source consultant_memo · Claim type absence · Polarity absence · Confidence high · Quote check exact, 100 of 100

   Cited by EN-02 · Filed under EN-02, EN-08

   See it on page 1, claim C-560f40e113

5. C-75d2a2cad3

   Flood fringe array rows should be checked against a local hydraulic model; if flood levels are higher than mapped, those 14 acres may need to be dropped.

   if flood levels prove higher than mapped, those 14 acres may need to be dropped.

   Stormwater, Floodplain and Drainage Memo - Tamsin Ridge Solar and Storage Project · DR-0019 · Page 2 · 2023-06-05

   Source consultant_memo · Claim type recommendation · Polarity neutral · Confidence medium · Quote check exact, 100 of 100

   Cited by AQ-02 · Filed under AQ-02, EN-08

   See it on page 2, claim C-75d2a2cad3

6. C-9f6b8123d8

   Landowners report floodplain fields flood for a day or two most springs.

   the floodplain fields flood for a day or two most springs.

   Stormwater, Floodplain and Drainage Memo - Tamsin Ridge Solar and Storage Project · DR-0019 · Page 2 · 2023-06-05

   Source consultant_memo · Claim type presence · Polarity presence · Confidence medium · Quote check exact, 100 of 100

   Cited by AQ-02 · Filed under AQ-02, EN-08

   See it on page 2, claim C-9f6b8123d8

7. C-db721b9fe7

   Landowners report Sallow Creek overtopped Linnet Road at the county bridge in the June 2019 flash flood.

   Landowners report that Sallow Creek overtopped Linnet Road at the county bridge during the

   Stormwater, Floodplain and Drainage Memo - Tamsin Ridge Solar and Storage Project · DR-0019 · Page 2 · 2023-06-05

   Source consultant_memo · Claim type presence · Polarity presence · Confidence medium · Quote check exact, 100 of 100

   Cited by AQ-02 · Filed under AQ-02, EN-08

   See it on page 2, claim C-db721b9fe7

8. C-ebc49abde3

   Basins have embankments no higher than 6 feet and about 9 acre-feet each, below the size requiring an ODNR dam construction permit.

   The basins have embankments no higher than 6 feet and hold about 9 acre-feet each, below the size at which

   Stormwater, Floodplain and Drainage Memo - Tamsin Ridge Solar and Storage Project · DR-0019 · Page 1 · 2023-06-05

   Source consultant_memo · Claim type absence · Polarity absence · Confidence high · Quote check exact, 100 of 100

   Cited by EG-02, PE-02 · Filed under EG-02, PE-02

   See it on page 1, claim C-ebc49abde3

• Keep arrays and equipment out of the flood fringe or run the local hydraulic model; confirm Linnet Road access during floods.
• Request design basis report, insurer hail and wind loss history, and any climate or wildfire screen.

Agencies