It rained last week. Your lawn still has very large puddles of water, and they are not going away, even though it stopped raining a couple of days ago. The neighborhood kids love to play in it, which is as natural as the rain itself, but your lawn clearly has drainage issues. A flooded lawn is an unhealthy lawn and should be a concern to the homeowner.
Why is water laying on the grass for any period of time a bad thing? Aside from being a prime breeding ground for mosquitoes, excessive water laying on the surface will eventually weaken and kill the grass. Grass roots need air to survive and maintain healthy growth, and that unnecessary damage can be prevented if lawn drainage issues are identified and corrected. .To identify the source of the drainage problem, look for these conditions:
Roof leaders or down spouts that direct rainwater on to the lawn.
Surface grading that is sloped toward a walkway or house foundation. The impermeable surface of a walkway or foundation acts as a dam, preventing any flow in that direction.
Adjacent properties that have been raised, draining water to surrounding lower areas, including your lawn.
Very flat grading that has no perimeter swale* to drain water. If the surface is absolutely flat with no drainage, water has no slope or direction to drain and will remain static.
* a swale is a very shallow ditch with gently sloping sides.
* a swale is a very shallow ditch with gently sloping sides.
Poor quality grading that has major depressions in the center. Water always collects in the lowest areas.
Hardpan subsoil. Hard clays and hardpan are impermeable to water and prevent surface water from percolating into the ground. Hardpan soils can be as little as a few inches thick, or many feet thick.All conditions must be collectively identified prior to taking remedial action.
Once you have determined why water remains on the grass, the source of the problem can be addressed and solved. Here are a few thoughts on solving drainage issues.
Once you have determined why water remains on the grass, the source of the problem can be addressed and solved. Here are a few thoughts on solving drainage issues.
Roof leaders, gutters and down spouts:
Roofs can collect a very large amount of water which must be directed away from the foundation of the building. Most down spouts have a little bend at the bottom end, which merely shoots the water a foot or two away from the wall, but it also directs the water onto the nearest lawn if there is inadequate drainage. Extend the down spout to direct water to a swale.
*Note that in most jurisdictions, it is illegal to connect roof leaders to the sanitary sewage system, which overloads sewage treatment plants and control systems.
*Note that in most jurisdictions, it is illegal to connect roof leaders to the sanitary sewage system, which overloads sewage treatment plants and control systems.
Surface Grading
1. Surface grading should always be away from the foundation of buildings to prevent damage to walls. Check grading and fill and raise the elevation at the wall if it is too low. Grading should slope a minimum of 4' away from the foundation.
2. If water is collecting along a walkway, or foundation, consider correcting the grade just enough to allow the water to drain away from any foundation, and allow drainage from one end.
3. If your lawn surface is lower than an adjacent property and collecting water from that property, consider top-dressing your lawn, raising it to the same elevation.As an aside, avoid any confrontational initiation of a "tit-for-tat" "lawn-raising competition. Instead, allow for a drainage swale between the properties. In this instance, a good drainage swale creates good neighbor relations.
Perhaps raising your lawn is not even necessary. Excavate shallow swales along the perimeter if adequate slope for drainage of the swale itself can be made available in doing so. An effective, properly constructed swale may be almost invisible, as it is contoured carefully and gently enough to be treated as any other section of grass. Above all, be careful not to create new drainage problems when adding more topsoil.
4. Correct any depressions in the surface of your lawn. Use a tightly-stretched line and small pickets to identify low areas. Fill the depressions with topsoil, roll to compact the soil, and re-seed or re-sod the grass. Most grading, if done correctly, will solve drainage issues.Perhaps raising your lawn is not even necessary. Excavate shallow swales along the perimeter if adequate slope for drainage of the swale itself can be made available in doing so. An effective, properly constructed swale may be almost invisible, as it is contoured carefully and gently enough to be treated as any other section of grass. Above all, be careful not to create new drainage problems when adding more topsoil.
5. If there is no other drainage available, consider installing surface drains and/or French drains. “Tune In” tomorrow to see “How to Install Surface Drains and French Drains.”
6. As a last resort, if there is no drainage pattern available, turn the excess water into a benefit. Excavate for a small pond, place a liner in it, add decorative cobbles, rocks, aquatic plants, a fountain, pump, and a filter to keep the water fresh, and turn it into a beautiful landscaping feature. Correct the balance of the drainage area to keep the surrounding lawn dry, lush, and healthy.
Now that you know how to solve lawn drainage issues, you will no longer need rubber boots to cut the grass.
