Drainage Damage Control

A very wet fall and winter has left many Triangle homeowners concerned about drainage problems, runoff and the resulting erosion in their landscapes. The helplessness we felt watching the destruction caused by water in Florida, New Orleans, Mississippi and the northeastern United States last year is a reminder of the power and significance of this precious natural resource to our environment.  

Thankfully, most of us will never suffer the devastation that our neighbors to the south, west and northeast encountered last fall. However, we must all be aware of the necessity to protect ourselves and our personal assets from the damage that water can do, and still consider the environmental impact of water conservation and correction of improper water drainage and runoff.
  
THE CHALLENGES OF CLAY
Landscape maintenance is important for the beauty of homes, and many homeowners spend great amounts of time and money on their landscaping. But proper drainage around the house is of greater importance than just appearance, especially in areas, such as the Triangle, where homes are built over large stratas of clay soil. Clay is an expansive soil that shrinks or swells throughout the seasonal changes, causing foundation damage.
  
The key ingredient that triggers the shrink-swell action is water. As clay soil loses water it shrinks, and when it absorbs water it expands. While it is important to keep clay soil wet around your foundation during periods of little rainfall, it is just as important to keep excess water from ponding around your foundation during rainy seasons. If excess water ponds around a foundation, clay soil will absorb it and expand. The more water, the more the soil can expand. It is not uncommon for the soil to lift the area above normal grade. Thus, when a dry period sets in, the soil will shrink and allow the foundation to drop more than normal. 

MAINTENANCE IS KEY
The first step in correction of many drainage troubles is routine maintenance. Make sure that gutters are kept clean and that the downspouts pipe the water to a driveway, drainage easement or practical lower spot in the yard. This may require that extra fittings or pipes be added to your gutter system. It is well worth the money, so that the foundation and surrounding areas are not compromised. Also, remember the laws of gravity, and that water will flow to the lowest point available. That said, you must ensure that water flowing over the ground flows away from your house and does not pool or puddle around the foundation. Make sure that the ground slopes away from the house and the foundation, so that surface water runs away from the building. Take a look at the earth around your house, and if it doesn't appear to be sloping at least slightly away, fix it.   Often, this basic routine maintenance will solve your drainage problem. If you've still got puddling in the yard (away from the foundation), improving soil structure alone may help solve the problem. As mentioned before, our heavy clay soil holds water and does not allow good drainage. Tilling the soil and adding organic material can be helpful, additionally providing a better environment for plant growth. For low spots in the lawn, leveling the area with additional topsoil may be the answer.  

WATCH THE WATER
Examine your property carefully the next time it rains. Watch  for runoff water from the roof, gutters and hardscape areas (driveways, patios, sidewalks), as well as the flow from your neighbors' yards. Does the water follow a neat pathway from the gutter downspout, along the driveway to the street and into the storm sewer? Or does a sudden downpour create a reservoir in your front yard that takes days to drain? Make note of your observations so you can make modifications to your property before you begin landscaping. 

DRAINAGE SOLUTIONS 
If you have significant drainage dilemmas, soil improvement or leveling may not be enough. A diversion, such as a swale, could be constructed to channel the water to a more desirable spot and prevent pooling in the yard. A popular solution is to create a dry creek bed, which provides an interesting focal point to the landscape during dry weather and serves a useful purpose when the rainy season arrives. Both swales and dry creek beds also help significantly with erosion.   

If neither of these options is feasible in your landscape, subsurface drainage might be the answer. Underground collection pipes, catch basins and channel drains can be installed to remove large amounts of potentially damaging water. French drains are another alternative, particularly around the foundation and in raised beds or planting areas. These drains collect water and allow it to slowly seep back into the ground.  In some situations, drain fields can be dug and filled with crushed rock to enable water to seep into the earth. While handy homeowners can install simple drainage systems, larger or more complicated jobs might be better suited to a landscape professional who is an expert in grading and drainage work. 

ERASING EROSION 
What about erosion caused by drainage problems? Planting vegetation often is the best solution, since the plants' roots will help to hold soil in place. Turf and ground cover are excellent remedies for eroding soil, particularly on a gradual slope. For more steeply graded areas, terraces may be built to slow the water flow. Terraces also can provide wonderful planting areas for the landscape. If there is a great deal of erosion present, it may be necessary for topsoil to be brought in to enhance the existing earth. Professionals who specialize in erosion and soil issues also have numerous products that can help to correct serious problems.   

A watchful eye, careful planning, routine maintenance and renovation in the landscape will help protect your property, add beauty to the landscape and help our natural environment stay healthy and clean. n Mary Kay Woodworth is a freelance writer.  This article originally appeared in NHI's sister publication, Atlanta Home Improvement, and is reprinted with permission.    What You Can Do   Here are some things you can do to protect your property from excess water and erosion and keep the stormwater system in your community clean.  

Reduce the amount of impervious surface area (sidewalks, driveways or hardscapes that prevent water from infiltrating the soil) on your property. Use concrete alternatives when planning new patios, paths or driveways-gravel, paving blocks, porous asphalt and other permeable materials.  

Rain gardens are a low maintenance addition to the landscape, intended to capture rainwater. Planted with vegetation that tolerates "wet feet," they are located in an area that will absorb runoff and hold it for a short period of time. Rain gardens reduce flooding risks significantly and allow utilization of excess rainfall in a positive way.  

If you have a boggy area in your yard due to underground springs or a low water table, surrender to it and plant shrubs, trees and perennials that love wet feet. Sweep your driveway instead of hosing it down. This saves water and keeps dirt out of the drainage system.  

Avoid using wood chips or mulch around yard inlets or swales. The wood chips can float and be easily moved by runoff water.  Add screens or guards to gutters to keep debris out of your drainage system. Install a removable connection between your downspouts and roof drains. Also, disconnect downspouts while cleaning gutters to keep debris out of the drainage system.  

Use a rainwater collection barrel to catch rooftop runoff. Many barrels have spouts so you can easily dispense water to carry to the parts of the yard where it's needed the most.