How do retention ponds help the environment?
The ponds are intended to collect stormwater and remove pollutants, so that cleaner water flows out of the ponds and into an adjacent stream. Retention ponds make up about 60% of all stormwater management structures in coastal North Carolina, so they likely have a big impact on water quality.
What is the purpose of a retention pond in a subdivision?
While it may look like a regular water feature, a retention pond serves a much greater purpose. Growing communities are at increased risk of flooding and erosion damage from excess stormwater runoff. Retention ponds are permanent structures designed to hold water flow for a short period of time, similar to a dam.
Why can't you swim in a retention pond?
As such, the sediment collected in the depth of these structures can contain heavy metals and contaminates. They can also have toxic algae blooms which can threaten the lives of children and pets or cause serious illness if ingested or placed in direct contact with skin.
Why does Florida have so many retention ponds?
The ponds provide two primary purposes: The flood volume held in a retaining pond reduces the impact on downstream stormwater systems. The second benefit is that they provide pollutant removal through settling and biological uptake.
Where does water from retention ponds go?
Retention ponds or "wet ponds" are ponds constructed to treat and store stormwater runoff. Retention ponds are permanent pools of standing water and eventually empty into a receiving water body.
Can fish live in retention ponds?
Oil, trash and lawn fertilizer flow into them. That's one reason why retention pond fishermen practice strict catch-and-release. Despite the debris and runoff, though, fish seem to survive - even flourish - in these environments.
Do retention ponds attract mosquitoes?
Properly designed, operated, and maintained ponds are not conducive to standing water and as such should not be fertile breeding grounds for mosquitoes.
Do retention ponds smell?
Stop The Odor In Smelly Retention Ponds Stormwater retention basins can emit a variety of noxious odors. Most odors are associated with blue-green algae blooms generated within the pond except when source water is high in organic matter.
What is the difference between a retention pond and a detention pond?
A detention, or dry, pond has an orifice level at the bottom of the basin and does not have a permanent pool of water. All the water runs out between storms and it usually remains dry. A retention basin or pond has a riser and orifice at a higher point and therefore retains a permanent pool of water.
How do fish get in man made ponds?
A pond that forms near other ponds may receive new fish from passing birds of prey dropping their catch. Similarly, fish roe that remains damp enough during a trip between ponds may wash off of the fur and feet of local animals as they move from pond to pond.
How deep should a retention pond be?
The maximum depth of a wet pond should be 12 feet with an average depth between 2 and 8 feet. (3) If a pond is too deep, stratification and anaerobic conditions may develop.
How deep is a retention pond?
3 to 9 feetHow Deep is a Retention Pond? Most retention ponds end up being anywhere from 3 to 9 feet.
Why do new housing estates have ponds?
In house-building it's known as Sustainable Drainage (SuDS) in which developers create features like ponds and grassy hollows, which catch heavy rains and provide the spin-off benefit of wildlife habitats.
What is the difference between a detention pond and a retention pond?
By definition, a detention BMP is an area where stormwater is temporarily stored, or detained, and is eventually allowed to drain slowly when water levels recede in the receiving channel. On the other hand, retention stormwater BMPs hold or retain stormwater on a more permanent basis.
How deep is a retention pond?
3 to 9 feetHow Deep is a Retention Pond? Most retention ponds end up being anywhere from 3 to 9 feet.
How do you build a retention pond?
Position the retention pond at a strategic low point in the area it will draw from. ... Dig the pond prior to digging the ditches. ... Use the backhoe to remove dirt from the center of the pond and position it around the edges, forming the pond's banks. ... Determine a location for pond water to exit when water levels run high.More items...
Why are retention ponds important?
Retention ponds are permanent structures designed to hold water flow for a short period of time, similar to a dam. In response to a storm, the pond’s water level fluctuates, reducing risk and saving the community from potential flood damage ...
What happens to pond water in a storm?
In response to a storm, the pond’s water level fluctuates, reducing risk and saving the community from potential flood damage and costly repairs.
Is it safe to live near a retention pond?
While there are some advantages to living near a retention pond —peace and quiet, green space, fewer neighbors nearby, and a decreased risk of flooding—potential buyers have other factors to consider. For example, there is a constant danger of drowning for families with young children.
What is a retention pond?
A retention pond is a man-made pond created by digging out or building an earthen dam to hold back stormwater runoff collected from a drainage area. It is designed to prevent flooding, prevent erosion, and improve water quality.
How does a retention pond work?
A retention pond works by storing stormwater and slowly releasing it back into the environment. It is often used as a way to treat polluted runoff from urban areas, which helps improve overall water quality downstream.
How to maintain a retention pond?
A well-maintained retention pond is an attractive asset that contributes greatly to the environment. To keep your pond healthy and looking great, here are some tips on how to maintain it:
Where you can build a retention pond?
Retention ponds can be built in almost any location, but there are a few things to think about before making a decision.
What are the costs associated with retention ponds?
Retention ponds are large-scale water reclamation projects implemented in metropolises. The initial cost is thus the expense of land acquisition, as well as the potential cost of not developing that land for another purpose.
What are the management and safety considerations associated with retention ponds?
A retention pond should be designed to reduce the risk of adverse consequences in the event of an embankment failure.
What is the purpose of a retention pond?
The grass and plants that surround a retention or detention pond assist to filter pollutants from storm water, but they should not be allowed to become overgrown.
Why are retention ponds important?
Retention ponds are largely used to improve the quality of urban runoff from residential neighborhoods , roads, parking lots, industrial sites, and commercial sectors, as well as to lower peak stormwater runoff rates by storing water temporarily during heavy storms. They must be kept in good working order and retention pond maintenance is the key to making sure they function properly.
What Is the Difference Between Retention and Detention?
Building a pond, or basin, is a common way to manage stormwater. Retention and detention are the two types of ponds or basins.
What happens when you monitor and maintain retention and detention pond vegetation, debris, and obstructions?
When you continually monitor and maintain retention and detention pond vegetation, debris, and obstructions, you may prevent corrective action on an inspection report and keep maintenance expenditures in check, just like any other area of your commercial landscape.
What happens to mucky pond stone?
On the retention pond stone, mucky pond sediment can accumulate. Then, in this muck, grass and plants take root, and the growth can frequently totally hide the stone.
Why is it important to take care of a stormwater pond?
Proper pond care is essential for preventing a variety of issues that can develop from a badly kept stormwater pond. Due to a lack of care, wildlife habitat loss, flooding, and erosion may occur. In many situations, damage is irreversible, especially if nearby bodies of water are damaged.
What is the effect of invasive vegetation on ponds?
Invasive vegetation thrives in the damp environment surrounding retention and detention ponds. Invasive grasses and weeds grow quicker than many native plants, and they can clog inlets and outlets that must be kept clear to enable proper water flow into basins. Plants have the ability to trap debris, which naturally collects around inflow/outflow locations.
What are the benefits of a stormwater retention pond?
Benefits of stormwater retention ponds include: Improved water quality in surrounding water bodies. Retention ponds manage stormwater quantity and quality , lessening the transfer of pollutants and chemicals into nearby water bodies. Aesthetic appeal.
Why are forebays used in ponds?
Forebays can be included in the design of a retention pond to "pre-treat" the stormwater before it spills over into the major water feature. Water is treated through sedimentation and nutrient uptake. Improved water quality in surrounding water bodies.
What is the purpose of stormwater quantity reduction?
Flood prevention. Stormwater quantity reductions minimize the risk of flooding in nearby areas.
What is runoff in water?
Stormwater runoff is excess rain water that flows into larger water bodies and local storm sewer systems largely due to the surrounding prevalence of hard surfaces, such as concrete. Large quantities of water that would ordinarily be absorbed into the ground in a more natural environment instead enter streams and lakes.
Why are retention ponds important?
Retention Ponds alleviate the expense of erosion and pollution. The intent of Retention Ponds is to reduce land erosion and pollution. As for pollutants, retention ponds are important in the removal of pollutants from the storm water run-off.
What is a retention pond?
Define Retention Ponds. Retention ponds refer to an artificial (man-made) pond. This pond is usually surrounded by vegetation. A Retention Pond can be dry or wet (by classification).
What is the best soil for a retention pond?
Get bio mix soils! This special mix of sand, silt, clay, and organic matter will give your retention pond a super-filtering and super purifying effect. To reduce storm water run-off it is important to install Bio Retention Ponds properly. For your unique bio soil mix design, contact your local building permit department for Build Code Compliance.
How does a retention pond help with erosion?
Storm water run-off can cause severe erosion and pollution. The cost to correct erosion and pollution can be expensive. Retention Ponds alleviate the expense of erosion and pollution. The intent of Retention Ponds is to reduce land erosion ...
How does a retention pond work?
How Retention Ponds Work. The purpose of retention ponds is to remove sediment from the storm water. The removal of materials like heavy metals, particulates, wooden materials, and organic matter, protects the Environment. The aquatic plants eliminate soluble substances, dissolved metals and nutrients.
What materials can be used to grow algae in a retention pond?
Materials like pet waste, grass clippings, and other organic materials that find passage into the various storm water drain provide algae to grow at a rapidly. This algae growth, will demand increased maintenance, to keep the retention pond in good working order.
Why are aquatic plants important?
Aquatic vegetation, plants and grasses in water help to withhold and or filter out the pollutants from the storm water. This filtration protects the quality of water, an important natural resource.
Why are retention ponds important?
Retention and detention ponds thus become crucial to control the flow of floods. Retention ponds can also facilitate the control of sediment and pollutants, as the natural process of the pond works to process the water without a lot of additional equipment required.
What are Retention Ponds?
Retention ponds are one solution to the problem of stormwater. These ponds collect stormwater as it runs off from the watershed, and they release them at a predetermined and slower rate via a low-flow orifice to avoid causing damage to the surrounding environment. Retention ponds, which are designed to contain water at all times, are similar to detention ponds, which are designed to let water flow out until they’re completely dry. In terms of construction, that difference means that detention ponds have their orifice at the bottom of the pond, while retention ponds have higher outflow points that allow some water to remain in the pond at all times.
Why Do Civil Engineers Use Retention Ponds?
Because the runoff of stormwater across these hard surfaces is so fast, diversion is required. Retention and detention ponds thus become crucial to control the flow of floods.
How does a retention pond work?
Retention ponds work because the outflow is controlled and restricted to normal levels for the runoff rate in the immediate area. Pipes, weirs and various orifices may all be part of the construction to help control the outflow.
What is the difference between a retention pond and a detention pond?
In terms of construction, that difference means that detention ponds have their orifice at the bottom of the pond, while retention ponds have higher outflow points that allow some water to remain in the pond at all times.
Why is proper diversion of water important?
Proper diversion of water is crucial in any community that experiences flooding issues during or after storms. Runoff from storms often causes damage to rivers and streams in the vicinity, and city sewer systems can quickly become overwhelmed by runoff.
Can a retention pond be used as a recreational facility?
In many cases, retention ponds can also be double-purposed to serve as recreational facilities. In developed urban areas, diversion of stormwater is an important issue. In fact, developers are often required by cities to maintain the pre-development discharge of water from a site, and retention ponds can be a relatively simple solution ...
Why should a retention pond be surrounded by natural vegetation?
Retention ponds should be surrounded by natural vegetation to improve bank stability and improve aesthetic benefits. Water is diverted to a wet retention pond by a network of underground pipes connecting storm drains to the pond.
What is a wet retention pond?
Wet retention ponds are a stormwater control structure that provides retention and treatment of contaminated stormwater runoff. By capturing and retaining stormwater runoff, wet retention ponds control stormwater quantity and quality. The ponds natural processes then work to remove pollutants. Retention ponds should be surrounded by natural ...
What is retention basin?
A retention basin or pond has a riser and orifice at a higher point and therefore retains a permanent pool of water. A retention pond looks like a regular pond, but plays an important role in controlling stormwater runoff.
Why are basins important?
The basins are important for storing and slowing stormwater runoff from nearby areas, especially areas with as phalt or concrete development. Stormwater runoff flows much faster from these surfaces than naturally occurring areas and needs to be diverted to ensure the runoff occurs at the desired rate. The amount of cleaning and treatment of the ...
What is the difference between a retention basin and a detention basin?
The main difference between a detention basin or retention basin, is the presence or absence of a permanent pool of water, or pond. The water level is controlled by a low flow orifice. In most cases, the orifice is part of a metal or concrete structure called a riser.
How does a dry detention pond work?
Dry detention ponds generally use a very small slope to divert water. The inlet needs to be not more than 15% higher than the outlet to ensure the correct amount of water flow through the system. The system works by allowing a large collection area, or basin, for the water.
What are basins meant to do?
Basins are meant to collect the water, and release it at a rate the prevents flooding or erosion. There are two main types of basins--detention and retention--and we will take a look at each of those today.
