Much of the central United States has experienced lots of rainfall this spring. The combination of precipitation, cooler temperatures and slower growth can create conditions where the course is saturated for several days. In this situation, cart and maintenance traffic can cause rutting and damage. That is not what you want to be spending time repairing early in the season.

Investments in subsurface drainage can help your course handle rainfall better and return to optimal course conditions sooner. Improved drainage can help produce firmer conditions that are more conducive to turf health, playability and withstanding traffic. When thinking about potential drainage improvements, it is important to remember the basics.

Water must flow downhill.

It may sound obvious, but for drainage to be effective it must flow downhill to move water from the source to the outlet. When installing drainage, use surveying equipment to ensure the pipe flows away from your problem area, don’t try to “eyeball it.” The slope of the drainage pipe should be greater than 1% (1 foot of fall over 100 feet of horizontal pipe run) to optimize drainage, although less slope can still be effective if the total fall available is very limited. If the drainage cannot flow downhill to the outfall, mechanical means like pumping water from a catch basin will be necessary to move water.

Water must have an outlet.

There must be a place for water to exit the pipe. If the pipe outlet is underwater or blocked, water will not be able to move through the pipe and out to the intended drainage area. For example, if you are draining a pipe into a pond, it should daylight above the expected water level. It is important to mark and maintain the drainage outlets to ensure nothing is blocking water from exiting the pipe. Vegetation loves to grow over and into drainage outfalls and animals may climb into pipes as well.

Map your system.

Many courses have subsurface drainage systems but the location of pipes, cleanouts and outfalls aren’t well documented. When installing new drainage, you can document the locations with GPS or a tracer wire. Even a quick drone photo of the drainage network is better than nothing. This allows you to find drainage infrastructure later if modifications or repairs are needed. It is difficult to maintain or improve drainage if the locations of pipes and outlets are unknown. Drainage scoping and cleaning services are also available to help identify and clear existing drainage to maximize drainage efficiency.

If you have any questions about how subsurface drainage could benefit your course, reach out to your local USGA agronomist.

Central Region Agronomists:

Zach Nicoludis, regional director, Central Region – znicoludis@usga.org

Tom Gould, agronomist – tgould@usga.org

Information on the USGA’s Course Consulting Service

Contact the Green Section Staff