Reasons For Flood Adjustments
Estimated yields and productivity indices used as the basis for farm assessments for bottomland soils apply to soils that are protected from flooding or a prolonged high water table during the cropping season because of high water in stream valleys. Soils that are subject to flooding are less productive than soils that are protected by levees. The frequency and severity of flooding are often governed by landscape characteristics and management of the watershed in which a soil occurs. For this reason, factors used to adjust productivity indices for flooding must be based on knowledge of the characteristics and history of the specific site. A wide variation in the flooding hazard, sometimes within short distances in a given valley, requires that each situation be assessed locally.
Flood debasements must be based on the site’s history and documented crop loss. The Illinois Department of Revenue asked counties to review their existing debasements and revise them as needed based on input from landowners, farmers, and farm managers. (One of the easiest ways to collect accurate yield loss is to have farmers complete a questionnaire).
Only the PIs of affected acreage that suffers actual, not potential, crop loss due to flooding should be adjusted. Flood debasement procedures should:
- identify the actual acres affected by flooding
- determine, from yield data, the documented extent of crop loss caused by each flood situation
- adjust the PIs of the affected soils by a percentage equal to the percentage of crop loss caused by each flooding situation over a multi-year (preferably 10) period
- monitor yield data in order to properly compensate for changes in a parcels flooding history
What you need to file for a flood adjustment on your farmland
- aerial map of the affected parcel (available in our office or online)
- flood history record (link to form)
- flood frequency and severity chart (link to form)
- certified yield information from the Farm Service Agency
How to Complete a Flood Frequency and Severity Chart
Use a Flood Frequency Chart to highlight areas of actual crop loss on an aerial photograph of a farm, along with producing proof to substantiate a claim. Yields of the past ten years reported for the Farm Service Agency, type of crop planted, number of acres planted for total farm operation by year, month(s) flooding occurred, by year, and the source of the floodwaters; creek, lake, river, etc. shall be used.
On an aerial map, highlight each separate area that has lost crops due to flooding within the last 10 years. Because there can be more than one flood area on a parcel, on the map, assign a “letter” (A, B, C, etc.) to each flood area, along with an estimate of the acreage of each flood area.
Write the “letter” for each flood area in the box on the chart that reflects the percent of crop loss, and the number of years in which loss occurred. Repeat this process for each flood area. A Flood Chart can accommodate up to 3 flood areas. Use additional charts if needed.
Note: You must use a separate chart for each parcel.
For questions or help completing the forms please call our office at the numbers provided on our contact page.