Requirements, recommendations and information for using swale without an underdrain as a BMP in the MIDS calculator
The anticipated construction period for this page is through July, 2014
Swale Side Slope and Main Channel Example (Version 2)
The runoff from a 1.4 acre parking lot surrounded by 0.359 acres of pervious turf area flows through sheet flow over one of the side slopes of a swale and into a swale main channel. The soils across the area have a unified soils classification of SW (HSG type A soil). A second side slope associated with the main channel does not receive runoff from impervious surfaces. Each of the swale side slopes are 800 feet long by 10 feet wide with a side slope of 5H:1V. The main channel of the swale is 800 feet long by 4 feet wide with a 2 percent slope. The swale main channel does not have an underdrain, bioretention base or check dams. The maintenance on the swale calls for mowing once a year. The following steps detail how this system would be set up in the MIDS calculator.