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When Is Drainage a Problem?

Have you ever experienced water in your swale and wondered why it is there and when it is supposed to disappear? Read the Frequently Asked Questions below to learn how most of Lee County's drainage systems function and when you should call the DOT Operations Division for action.


Q: What is a swale?

A: Swales are shallow ditches usually found between the road and your front yard. These swales convey water (mostly rainfall) to canals, rivers, ponds and lakes by gravity flow.

Q: How do Lee County's drainage systems work?

A: For the most part, the drainage systems of Lee County function by way of a series of swales. You may notice that there are practically no hills in Lee County. Therefore, there is not a lot of slope for the swales to convey the water quickly to the canals, rivers, ponds and lakes. Because swales convey water by gravity flow, it is common to see swales throughout Lee County at different depths. This explains in part why some driveways have pipes under them and some do not. Having a swale provides a place for the water to go, rather than flooding private property. Swales also keep most of the water off the road, which provides a longer life for the road.

Q: Should a swale fill up with water during a rainfall?

A: It is not unusual for the swale to fill up with water during a rainfall. During a heavy rainfall, the water can fill up beyond the swale.

Q: After the rain has ended, how long should it take for most of the water to drain from the swale?

A: Measure the amount of water in your swale just after the rainfall has ended. Then measure the amount of water in your swale 12 to 36 hours later. If there is a difference, you know that the water is running off and your swale is working properly. Swales are designed and permitted to meet local and state water management standards at the time of construction. Swales constructed after 1984 are designed so that all or the vast majority of the water is gone in 36 hours, as required by the South Florida Water Management District.

However, some of the water in deeper swales or swales constructed prior to 1984 may never disappear during the rainy season due to a high groundwater table. The groundwater table is a fluctuating upper surface of a saturated zone. According to the Soil Survey Manual produced by the United States Department of Agriculture, 56.8 percent of Lee County's seasonal high water table is 0 to 1 foot below the existing ground level, and 32.3 percent is 1 to 3 feet below existing ground level.

Q: What can I do to prevent drainage problems?

  • Do not re-dig, re-grade, fill or alter the swale in any fashion.
  • Do not plant trees, install sprinklers or perform landscaping in the swale.
  • Avoid driving and parking vehicles in the swale.
  • Do not distribute grass clippings in or near the swale.
  • Do not pipe swales without local and state approval. Piping prevents runoff from percolating into the ground, which aggravates the problem.


Q: If I have a drainage problem, who should I call?   

A: File a Request For Action (RFA) online form or call the Lee County DOT Operations Request for Action line at (239) 533-9400 Monday through Friday between 7 a.m. and 5 p.m. Be prepared to give the following information:

  • Your name
  • The address of the problem
  • Your address if different than complaint location
  • Daytime telephone where you can be reached
  • The last date and time of rainfall
  • The depth in inches of water in swale

A field inspection will be done, and the results along with other data will be reviewed by DOT staff.

Q: When should I call or submit an RFA form?

  • Not during a rainfall, unless water is endangering your dwelling or property. It is not unusual for swales
        and ditches to overflow during our frequent heavy rainstorms.
  • 72 hours after rainfall has ended, and a majority of water in the swale has not drained away.
  • When your swale is holding more than 6 inches of water and other neighbors' swales are dry.
  • When you spot an obvious high spot, low spot or blockage, such as a crushed driveway pipe or a
        pile of dirt or debris in the swale or pipe.


Charlotte County Florida CENTS Committee, South Florida Water Management District, U.S. Department of Agriculture, Soil Conservation Service