By Douglas Smith
Smith Custom Builders
There are many types of wall supports for bayous and ravines that can be found in use in the Houston area.
Just by looking around you can find block systems, anchored netting systems, sheet-driven pile systems, post and timber systems, concrete retaining wall systems and gunnite systems to name a few.
From all these variations of systems, there are as many types of each available on the market. So the question is, which system is right for your individual needs?
The answer lies both in your budget, and the grade (slope) of the bayou or ravine walls.
Most are made from block systems that stack with special inserts that hold the blocks together. These systems must have a concrete base or grade beam installed beneath as a support.
As always, this type of support beam must be engineered for each desired site, as ground conditions vary greatly all over Houston.
Anchoring netting systems can be designed to grow vegetation through the netting, while slowing or preventing erosion to most slopes. This system uses long rods that are drilled into the bank itself, parallel to the nearest level surface. These anchoring rods vary in length depending on the holding strength needed. The netting is tied to these anchors, and lays on the surface.
Driven sheets of corrugated steel are used when the area in question is too steep and near waterways that can rise quickly. This is common place near the Houston Ship Channel and rivers. This system can be applied to smaller areas if needed.
Post and timber systems utilize special designed posts, which look like the letter “H” turned sideways. The timbers slide into the slot in the “H” post. This provides strength if the posts are sized properly, and set at the proper depth.
For the money, the post and timber system is the best, and you must use treated wood for this system to last.
Concrete systems use formed and poured walls for holding strength. This system, pound for pound, will hold the most weight of any of the mentioned types. It also is the most expensive, and in some cases it is necessary. If your home’s foundation is dependent on one of these systems to hold it weight, this is the type to use. This system normally will utilize drilled footings deep into the ground, allowing it to perform for many decades.
Gunnite systems are built like a pool, except you use drilled anchors into the slope first, then attach a netting. A special concrete mixture is sprayed onto the netting for added strength.
Many factors must be taken into account when using this method. Thickness of concrete, type of wire and how to release water pressure from behind the surface, all must be figured in.
If the grade or slope is not too severe, or too steep, there are many landscaping methods that can be applied to slow or stop rain water from trenching the dirt. This can be done by most landscape companies.
This article was provided by a member of Greater Houston Builders Association’s Custom Builders Council. For more information contact the Greater Houston Builders Association, c/o Custom Builders Council, 9511 W. Sam Houston Parkway N., Houston, TX 77064; www.ghba.org/cb_council.asp; or 281-970-8970. |
