Houston Detention and Retention Ponds Services
Detention and Retention Ponds are Critical Flood-Control Structures
In urban areas, detention and retention ponds are essential flood-control structures. In cities, runoff can be a threat, as rainwater travels much faster over concrete than over natural soils. Controlling this flow is key to avoiding floods, and that’s where detention and retention ponds come in. These simple basins are excellent flow regulators and slow the rate of water runoff.
As simple as they are in function, though, it takes a lot of planning, equipment, and manpower to create them. That’s why expert Houston site preparation teams are called in to do the job.
What’s the Difference Between a Detention and Retention Pond?
Detention and retention ponds serve the same general purpose – modulate the flow of water through residential and urban centers. This provides a buffer during periods of heavy rainfall and helps prevent flash floods from occurring. Both detention and retention ponds are sloped during construction to meet flow specifications, and it’s this grade that determines how fast the water drains.
There are notable differences between the two types of ponds, though, so here’s a closer look at each:
Detention ponds are dry ponds, which means they circulate water through the pond faster and empty out between rain events. Detention ponds do this with a riser that’s built flush with the pond’s base, so water can fully drain.
Detention ponds are normally built on larger sites and are more common in drier regions, including western and southwestern parts of the country. In these areas, detention ponds are ideal for capturing snowmelt as the weather warms up after winter.
While detention ponds aren’t as effective as retention ponds at controlling water quality, concrete structures can be added that capture litter and promote better sediment settling.
If cost is a concern, detention ponds tend to be the budget-friendly choice. Maintenance is required, but as long as the riser is kept free of debris, detention ponds are a reliable flood control method.
Retention ponds are wet ponds, which means they retain a minimal level of water even during extended dry periods. In retention ponds, the riser is elevated from the pond’s base, so water drains only when it reaches a certain level. Water is usually fed into retention ponds via pipes connected to nearby storm drains. In this way, retention ponds are “hubs” where runoff is diverted from other areas.
There are multiple benefits of retention ponds, beyond aiding in flood control. Retention ponds add value to land (detention ponds usually reduce land values) because many people like having a nearby pond. Wildlife prefers it, too, and retention ponds can serve as new habitat areas.
Further, retention ponds capture water for longer, which gives sediments – including fine sediments – time to settle. This is a natural method of improving water quality.
Regular maintenance is particularly important for retention ponds. In addition to keeping the riser clear, vegetation must be maintained, and erosion prevented. Preventing algae blooms is also essential with retention ponds.
How are Detention and Retention Ponds Built?
Whether you’re considering a detention or retention pond, the job requires extensive site planning and preparation. This is what the construction process typically includes:
- Locating and marking the pond – Before site preparation can begin, the pond’s perimeter must be marked out for excavation purposes. The dirt work team will also need to locate any underground utilities and ensure they are accounted for during initial excavation.
- Clearing and grubbing the site – Prior to excavation, the pond site must be completely cleared and stripped of any vegetation, debris, or other undesirable materials. Grubbing is also necessary, as the pond will be dug out of the ground. During grubbing, the site prep team will remove vegetation down to their root systems, including tree stumps.
- Creating the embankment’s foundation – The embankment’s foundation is the first part of the pond to construct and is responsible for stabilizing the above embankment and bearing load. Of particular importance is establishing where the outlet apron will go.
Once this area is established, excavators go to work removing surface soils and developing the pond’s general shape.
- Install the spillway pipe and riser – With the foundation in place, the primary spillway can be installed. The spillway is responsible for draining water from the pond and consists of a riser and pipework. Both must be installed on a stable, even foundation. Workable, clay soils are placed around the pipe bedding and compacted to the same density as the foundation soil.
The riser is embedded into the concrete pipework to counter buoyancy, and the riser’s base is typically surrounded by stone. Many projects also call for a trash rack and concrete apron to be installed, too, and these are placed at this time.
- Grade the embankment – Once the primary spillway is in place, the pond’s embankment can be graded to specifications using dirt recovered from initial excavation processes. It’s critical that the right embankment slope is established to reduce erosion. Once the embankment is graded, the earth is compacted for additional stability and erosion resistance.
- Install an emergency spillway – Emergency spillways are extremely important for areas that flood regularly. During intense rain events, the emergency spillway acts as a secondary outlet when the primary spillway’s capacity is insufficient. This spillway must be positioned so that it also empties into the receiving channel, without compromising the embankment’s integrity.
At this point, additional erosion control methods, such as adding vegetation, may be deployed.
Need Better Flood Control? The American Paving Team is Your Detention or Retention Pond Expert In Houston
Retention and detention ponds are essential to any city’s flood control efforts. They’re simple in design, effective in practice, and can add value to some properties. However, they must be developed while adhering to construction tolerances. Poorly graded ponds are quickly overtaken by erosion and may not drain properly – which defeats the purpose.
Fixing poor construction is always more costly and time consuming than building it the right way, the first time. That’s what the American Paving team prioritizes. Our dirt work services adhere to local and state guidelines, and our experience allows us to head off project challenges before they cause delays. This, coupled with our deep manpower and equipment resources, means American Paving can develop a full range of detention and retention ponds.