Hays ? Terrace rebuilding is a subject we hear a lot about, but lately some new questions have been raised. Do I need to rebuild every terrace in the field, or can I just rebuild every other one?

To decide about rebuilding, first you need to know something about how a terrace system is designed. Terraces are designed to contain a 10-year rain without overtopping. This means they can hold the total runoff from a rain that would occur once in 10 years on the drainage area above the terrace.

When terraces are rebuilt, every terrace in the system needs to be restored to original design height for the system to have adequate capacity and work properly. If only every other terrace were rebuilt, the old terraces, with their low capacity, would overtop. The overflow runs down the slope and is caught by the rebuilt terraces. Since these terraces are only designed to handle the runoff from the area above, the excessive runoff from the old terraces would cause the newly rebuilt terraces to overtop.

If terrace spacing is a problem, an entire new system may help. Spacing can be adjusted by installing new terraces with wider channels. In certain situations, a new system may improve alignment and farmability. Visit your local U.S. Department of Agriculture’s Service Center and talk to the NRCS or conservation district staff for more information.

For more information about NRCS programs, visit the Kansas NRCS Web site at www.ks.nrcs.usda.gov.