Drainage Systems

We want to educate ourselves before taking the plunge and putting in a drainage system. Can Exterior Worlds help us out?
For more than 20 years, Exterior Worlds has seen our clients through the process of putting in a drainage system. Because we live at only about 40 feet above sea level, not to mention the 21 major bayous in the area and the regular appearance of tropical storms, Houston landscapes require such a system.

Here are the main elements required for landscape drainage:

• Gutter downspout tie-ins. These tie-ins are designed to take water from the gutters to the landscape drains. Made of plastic, metal or brass, they sometimes have a side cleanout with a see-through grate so they can be easily inspected for clogs.
• Catch basins, or yard drains. Catch basins can be placed under downspouts when it is undesirable or not possible to tie into the gutter. Catch basins are usually a plastic or concrete box that uses a plastic or metal drain grate cover to filter out yard debris.
• Deck drains. Your deck design should allow for a slope either toward drains or drain into the landscape beds. Special decorative drain covers, made of metal, brass or stone, can help with the visual impact.
• Channel drains. These drains are long and narrow usually placed between main structures and paving or at the edge of a patio or deck.
• French drainage. French drains are small ditches that are filled with undersized rocks or gravel and are designed to take water away from saturated soil.

What about local regulations and permitting issues?
Local ordinances are beginning to follow the model used by the Memorial Villages that require minimum pipe sizes, temporary drainage systems, engineered drainage plans, flow rates, calculations, as/built plans, and topographic maps.

All of these measures were put in place to protect homes and private property. In so doing, they also help your plant material to flourish into a full and healthy landscape. Your drainage contractor must have a complete understanding of the demands of the local governing body or you, as the homeowner, could wind up in the middle of a very expensive mess.

How will this system affect the rest of our landscape?
Proper drainage positively impacts residential landscape maintenance. By draining water from low-lying areas, it prevents standing water that can cause mosquito breeding grounds, soggy landscaping and slick surfaces. Proper yard drainage is essential for the care of your lawn because it moves water off your property quickly, thus encouraging healthy grass. It also permits your maintenance crew to perform their regular lawn service duties.

During installation of a drainage system, we recommend that trenches be hand-dug around trees to minimize damage to them. Or pressurized water can be used to dig deep trenches around the roots. You can also tunnel under tree roots by using compressed air. These tree preservation methods expose roots so they are not torn.

Drainage and irrigation systems can work in concert with each other. In fact, landscape designers or landscape architects can develop a whole-system approach so that the hardware of both systems is hidden as much as possible.