Wet Yard After Storms - Solving Drainage Problems
Puddles and sogginess for several days following rainstorms.
Persistent puddles and sogginess for several days following rainstorms can be caused by poor grading, poor percolation of water through soil, or often both. Observe your property before, during, and after the next storm.
Choose One: Where and How Big is the Wet Area?
Wet Near Gutters
and Downspouts: The sogginess is confined to areas around the gutters
and downspouts. »
The sogginess is confined to small, well defined soil depressions.
Poor grading prevents stormwater from flowing off the yard. Instead, stormwater is held in depressions until evaporation or infiltration into the soil eliminates the wetness.
A practical and environmentally beneficial option is to replant the wet area with
water-tolerant plant species, preferably native. »
If you wish to eliminate the soggy depression, you can do so by filling or re-grading the depression. »
A soggy spot can be improved by replanting with water-tolerant plants. Plants will aesthetically improve the soggy spot, soak up the remaining water, attract beneficial pollinators, and they can also slowly improve drainage by loosening the soil with their roots and organic matter.
To eliminate wetness in small depressions, the depression can be filled in and graded.
- Remove all leaves, plants (including grass) and other loose material from the depression.
- Fill the depression with topsoil (or if near the foundation of the house, with fill soil) and compact using a tamper or a similar device. Use soil with relatively high clay content.
- Grade the filled-in depression so that water will not stagnate. Soil should be graded so that water flows away from the foundation walls to prevent any water damage.
- Cover the depression with sod, grass seeds or other vegetation. If sod is used, make sure the final elevation does not cause water to collect on the up-slope side. If grass seeds are used, consider protecting the seeds with a thin layer of topsoil (approximately ¼ of an inch) followed by a thin layer of straw. This thin layer of soil and straw will help protect the seeds from birds and also enhance germination.
Sogginess around foundation walls and downspouts may be a result of overflowing gutters or downspouts and sump pumps that are discharging improperly.
Poor grading around the foundation walls may exacerbate these problems.
You may need to fill in depressions that have
formed near the downspout. Land around your house should slope away from
foundation walls. Ideally, a 5% grade
should be maintained for a distance of ten feet around your home.
1. Gutter inspection and maintenance
- Inspect the outer portion and underside of gutters for streaks or watermarks.
- If streaks are present, clean gutters. Gutters should be cleaned free of debris at least once a year. This should be done more frequently if you have trees close to your house.
- If gutters appear to be clean, observe how they function during normal rain events. A spillover of roof runoff is an indication of an undersized gutter system. Consider installing larger gutters.
Stormwater from downspouts and sump pumps can be a significant source of runoff. If downspout or sump pump flows are causing soggy conditions in the yard, they can be redirected through extensions to a better graded area that flows away from the house. At a minimum, a downspout should discharge onto a splash block to direct flow away from the foundation wall and prevent soil erosion.
If a splash block is not sufficient, downspout extensions (non-perforated corrugated plastic pipes) can be attached to the downspouts to direct flow further from the house. The pipes can either be laid on the ground surface or buried underground.
Whenever you redirect stormwater, make sure it is discharged to a suitable area. Downspout extensions can be used in combination with swales, rain gardens or other structures that redirect or capture runoff », especially if a suitable area is not within a reasonable distance.
For sogginess that affects areas of the yard that may be too large or
difficult to simply fill in, re-grade or replant, there are other
solutions. Runoff can be intercepted,
redirected or captured and stored to minimize the amount of water that
accumulates in the problem area.
- Intercepting or redirecting runoff provides an opportunity to safely discharge the volume to a place beyond the problem area. This can be done using swales, French drains, catch basins or downspout and sump pump extensions.
- Capturing and storing runoff is environmentally beneficial and in some cases, allows it to be repurposed in a useful way. This can be done using rain barrels, cisterns, dry wells, soil amendment or rain gardens.