Water Quality: My Place on a Stream
Module 3

Lesson 3 - Tips For Living In or Near a Floodplain, Information Sheet

Acknowledgement: Taken from "Living on the Land 2001"

  1. Donít.
  2. If all your property is in a floodplain, sell (or gift it) it for open space.
  3. If you retain ownership of the open space in a floodplain, donít build on it; sell (or donate) the conservation easement.
  4. If you must build on it, put the building on stilts or make the bottom level flood-compatible space, such as carports, garages, unfinished storage areas, etc.
  5. If you must fill an area to raise your house above the flood level, keep the raised area small. The flood map will change because of your filling. Also, the 100-year floodwaters will deepen after the watershed is developed or when upstream neighbors increase the speed at which water flow though their streams.
  6. If you must fill an area to raise your house above the flood level, only elevate areas that are already high and well away from the actual streambank.
  7. Leave the stream-side area in natural vegetation, even if that may increase flood level. The higher water will move more slowly and thus will cause less damage.
  8. Disperse the water running off your house and driveway rather than draining it quickly to a stream, ditch, or gutter. Detention basins or French drains allow water to slowly pass.
  9. If your neighbors insist on a levee or an engineered floodway, suggest strongly that it be set back from the edge of the stream, leaving the stream room to flood and move over a wide area through time.
  10. If your stream comes with trees, shrubs, snags, big rocks, or dead wood in or near the water, leave them for the stream to use for energy dissipation. Clean out trash such as sawn firewood, boards, litter, shopping carts, etc.
  11. If your stream is narrow and meandering and floods frequently, remember that it depends greatly on streambank vegetation to keep the banks stable. The banks will move slowly by the process of erosion and bank building to keep the same basic stream form and pattern.
  12. If your stream no longer overflows onto its floodplain every year or two as it used to, watch out! After incision, streams erode banks as they create a new floodplain. This is a natural process of recovery, and ultimately leads to renewed stream health and stability. So, keep your house or other valuables out of the way. In the very long term, the stream and flood level may rise to the old floodplain level.
  13. If you must protect a bank from erosion that cannot be tolerated, even if it gives back a floodplain to the stream, get outside help to consider all upstream and downstream effects of your project. Make sure you get the needed permits.
  14. Avoid straightening the channel, using concrete near a channel, dredging, smoothing land surfaces that water flows over or against, or obstructing flow with an in-channel dam. If you must do so, hire a reputable engineering firm to consider all upstream and downstream effects of your project and make sure they get the needed permits. If your project negatively impacts your neighbors, be prepared for the consequences.
  15. If you build a pond or sediment detention basin, do so away from the stream channel so that it will not have to handle floodwaters and sediment coming from the watershed. Also, make sure that it includes a well-armored spillway and follows proper pond engineering practices, etc. (See USDA NRCS. 1997 (revised ed.) Ponds Ė Planning, Design, Construction.)
  16. Do not drain or fill a wetland. Draining or filling wetlands without required permits may result in heavy fines.
  17. Make sure land uses in a floodplain are flood-compatible, such as parks, recreation, open spaces, agriculture, wildlife habitat, parking lots, etc.
  18. Make sure that all land uses are compatible with local stream ordinances.