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Terrace
An earthen embankment around a hillside that stops water flow and stores it or
guides it safely off a field.
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How it works
Terraces break long slopes into shorter ones. They usually follow the contour. As water makes
its way down a hill, terraces serve as small dams to intercept water and guide it to an outlet.
There are two basic types of terraces—storage terraces and gradient terraces. Storage terraces
collect water and store it until it can infiltrate into the ground or be released through a
stable outlet. Gradient terraces are designed as a channel to slow runoff water and carry it
to a stable outlet like a grassed waterway.
How it helps
 Both water quality and soil quality are improved.
Terraces with grass on front or backslopes can provide nesting habitat.
Planning ahead
Will other conservation practices be used in conjunction with terraces to
prevent sedimentation?
Tech notes
Chisel the parts of the terrace that will be farmed to loosen compacted
soil.
Fertilize and seed according to NRCS recommendations.
Grassed backslope terraces have a farmable frontslope with a 2:1
backslope (2 foot horizontal to every 1 foot of vertical drop.)
Narrow base terraces have 2:1 slopes on both the frontslope and
backslope.
Broadbase terraces should not be built on slopes greater than 8%.
Farmable slopes should not be steeper than 5:1. *
Terraces are designed to control runoff.
Maintenance
Avoid farming too close to intakes.
Remove sediment build-up in the channel to maintain the required
water-
holding capacity.
Repair sections of embankment which have eroded or have excessive
settlement.
Fill settled or eroded areas in the tile trench.
Repair or replace damaged intakes.
Remove sediment build-up and trash from around the intake.
Control rodents or burrowing animals, weeds, brush and trees.
Reseed and fertilize as needed to maintain good vegetation.
* Check local recommendations.
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