3 Landscaping Drainage SolutionsNovember 6, 20150
In order for your landscaping to be healthy and look its best, it is critical that it drain properly. Having the right landscaping drainage solutions is especially critical whenever there is a high water table, dense soil or flat land.
If the right drainage systems are not in effect, water can collect and drown plants, undermine structures and turn your new landscaping into a swamp. The potential for so much damage makes it imperative to address drainage issues before designing and planting any new landscaping.
Does Your Landscaping Have Drainage Problems?
The first thing you need to do is analyze your backyard and its nature. You may need to get help from a professional landscape architect in order to assess what the exact topography is. The site might appear very flat, but there can also be spot elevations which can potentially cause problems as well.
Another factor that often plays an important role when it comes to drainage is ground water. This relates directly to rainfall patterns. For example in the South in low lying areas, the water table is often only a few inches underneath the surface. These types of conditions can limit what your planting options are and also cause all kinds of construction problems.
Rainfall is often a catalyst for drainage problems to emerge. In areas where heavy downpours are quite common, sites that drain poorly can flood very quickly if the proper drainage solutions have not been implemented. When heavy rainfall is added to a high water table, the potential for damage to occur increases substantially.
Test Your Drainage Situation
There is a simple test that you can do to determine what is taking place underground. Dig a hole that is approximately two feet wide and deep. Fill the hole with water. If it drains completely in around one hour, you have excellent drainage.
You may have a problem if it takes approximately 12 hours for it to drain, and if it takes over 24 hours you have a serious problem that can negatively impact the deep roots of your shrubs and trees.
3 Landscaping Drainage Solutions
1. Surface Drainage
Sites with clay soils tend to have problems with water lingering on the surface. In theory, all lots are graded so that water flows from the backyard down into the side yard to a storm drain or the curb. However, lots are not always properly graded by builders and water becomes trapped.
This causes muddy areas in gardens and lawns. In order to combat this problem, surface grading is one drainage solution that can be used to help ensure there is sufficient fall in order for the water to drain.
One ancient drainage solution is the French drain. It gathers the water and then a place is provided underground where it can percolate down through the dense soil. Basically this solution entails digging a trench and then filling it with gravel and sometimes a perforated drain line as well.
Geotextiles or roofing felt is then placed over the gravel and then the soil is replaced. In order to drain the trench, the surrounding area gets graded so that the water will not gather on the ground’s surface any longer and cause problems.
2. Underground Drainage
If the soil contains a hard pan layer, the whole site might suffer from standing water and poor drainage. It is too challenging to try and use spot solutions in this type of situation. You need site-wide grading along with a drainage plan that includes an underground piping system that is fed by trench drains or drop inlets. New plastic piping is easier to install and it is also easier to remove water from the site and into the storm drain directly.
In areas with high rainfall like the Pacific Northwest or Florida, your drainage plan might be the most critical aspect of your landscaping. These types of drainage systems are more expensive to install, but they are well worth it.
Where a storm drain is either inaccessible or nonexistent, the type of system can flow into a sump underground. It is basically large hole that is filled with gravel. The water stands in the sump until it finally drains away.
3. Use Water Loving Plants Or Raise The Planting Area
Low lying areas that have a high water table are difficult to landscape with. During the growing season, plant roots that are in saturated soil do not get a sufficient amount of oxygen and rot quickly, similar to what happens to an over-watered house plant. Certain plants that grow in wetlands and river bottoms can thrive in a high water table landscape.
Some good options include riparian species that are from local swamps, fens and bogs since they have adapted naturally to your soils and climates. Another good candidate is trees that come from similar wetlands from other areas of the world. They add more diversity than what may be available from plants that are native to your area.
Another drainage solution for landscapes with a high water table is raising the planting area. This option is expensive but also very effective.
Raised beds and planters can often be used to help combat the problem of a high water table.
Too much water can wreak havoc on your gardens and lawn. The 3 landscaping drainage solutions above are some of the most effective ways to combat poor drainage conditions. To avoid problems in the first place, consider these solutions before planning any new landscaping project.