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Nuisance Drainage

When Minor Flooding Becomes a Major Headache

Nuissance Drainage page bannerSince its inception, the Flood Control District has focused much of its attention on mitigating damage from major catastrophic flood events. Neighborhood drainage issues, however, are also an important concern. Even small washes can cause significant damage in localized areas. This problem is most often encountered in older subdivisions in which drainage design does not meet current standards and in outlying areas of the county in which no drainage infrastructure exists, as well as areas that were developed prior to the establishment of the District. Neighborhood drainage is fortunately a relatively rare occurrance in newer subdivisions, but does occasionally present problems due to unforeseen events or designs that are mis-matched to the hazard.

The laws that the District is bound to limits the size of washes and floods that it can regulate to those washes that convey 100 cubic feet per second (cfs) or more during the base flood or to mapped floodplains. This is an important point to keep in mind when talking about neighborhood drainage, as the District has no authority to regulate development affecting such relatively minor hazards. However, the District does recognize that while 99 cfs is below our regulatory authority, it is a significant amount of water if it is going straight into your house. That amount of water is enough to fill a 2000 square foot house 1 foot deep with just 20 seconds, assuming the unlikely scenario of unrestricted flow into the house. Those numbers, however, illustrate how even relatively minor flooding that falls below our regulatory threshold can cause a major headache.

A significant percentage of flood damage occurs from non-regulatory flows. If you are impacted by such flooding and you believe the flooding was caused by a neighbor, the District recommends approaching the neighbor in question, calmly explaining the problem and the hazard it has placed you and your property in, and ask him or her to remedy the situation. If this proves unsuccessful, you may want to consider private litigation.

If the hazard is from a source that is regulatory, the District may be able to assist you in addressing diversions from neighboring properties. However, flooding is often a result of an unusually severe storm which is out of our control, and may be worsened by development in the floodplain that are impractical for the District to regulate. Our Drainage Complaints page has more information regarding this matter.