Calhoun Drainage District No. 107
Calhoun County, IA | Water
ISG worked with local landowners to develop a drainage solution that was more cost-effective while also ensuring water quality and slope stability.
Landowners in Drainage District No. 107 wanted to replace the tile system; however, after analyzing the cost comparison, ISG proposed the more cost-efficient option of a two-stage channel construction.
The open channel for Drainage District No. 107 was constructed as a two-stage ditch for enhanced water quality and slope stability. The lower portion (first stage) of the channel was constructed with 2:1 side slopes, and the upper portion (second stage) of the channel was constructed with 1.5:1 side slopes. A 3-foot bench was constructed between the two stages at the normal flow depth calculated for the channel. These dimensions create a footprint with a channel featuring an approximately 2:1 slope continuous through the entire side slope. The dimensions result in a minimum requirement for right-of-way acquisition needs.
Water quality for the entire drainage district was improved while providing the recommended drainage to the adjacent row crop fields. As a result, this project will maximize future crop production in the area.