Using a Bioretention Pond Forebay. Forebays are often used to capture a first-flush or water quality volume (WQv) before the runoff hydrograph reaches the main detention pond. There are two approaches you can use in the software: Option 1. Remove the WQv from the inflow runoff hydrograph. When off-line structural controls such as bioretention ...Sep 3, 2020 ... 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 ... Stormwater ponds are defined as either retention or detention ponds. In Florida, dry stormwater ponds and swales are dry for most of the year but become inundated after rain events. Wet stormwater ponds are typically inundated year-round. Retention ponds keep all water within them and prevent it from moving downstream. Mar 23, 2021 · Detention vs. Retention Stormwater Ponds: The Water Rights Implications. There are two types of stormwater ponds: detention ponds and retention ponds.Detention ponds only detain water for a short period of time, then release the water to a natural watercourse, while retention ponds retain the water for an indefinite period of time. Are you planning to build a beautiful pond in your garden? One of the essential components you will need is a high-quality pond liner. The right pond liner will not only ensure tha...A retention basin, sometimes called a retention pond, wet detention basin, or storm water management pond (SWMP), is an artificial pond with vegetation around the perimeter and a permanent pool of water in its design.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. In response to a storm, the pond’s water level fluctuates, reducing risk and saving the community from potential flood damage ...The Guidebook provides a technical resource for both Phase I and Phase II NPDES communities. This Guidebook provides the inspector, program manager, designer, and owner (i.e., responsible party) with an understanding of common stormwater pond and wetland maintenance problems and possible solutions.Feb 1, 2020 · 8 Advantages and Benefits of Retention Ponds. Retention ponds improve water quality. Remove pollutants and sediments. Serve as storage facility for controlled release of water. Diminish the threat of flooding. Enhances the Environment and wildlife. Easy to construct and maintain if adequate space is available or provided. Calculation procedures for detention ponds Detention Pond Routing Basics How the Storage-Indication method works and how to troubleshoot pond routings Stage Storage Calculations Contours, Trapezoids and Underground Chambers Stage Discharge Calculations Culverts, Orifices and Weirs Sloped ...Mar 16, 2022 · Detention Ponds. A detention pond is a dry structure that has a riser located at the bottom of the basin. Whenever water flows into the detention pond, it is more likely to drain right out and stay dry. Detention ponds may have turf or wild grasses. Like retention ponds, they may require a large swathe of land to create one, but their main ... Description. Retention ponds can provide both stormwater attenuation and treatment. They are designed to support emergent and submerged aquatic vegetation along their shoreline. Runoff from each rain event is detained …According to the United States Environmental Protection Agency Stormwater Best Management Guide, “while detention basins rely on solids-settling processes, retention ponds remove dissolved nutrients through several physical, chemical, and biological processes in the permanent pool.”. No single BMP can solve all the issues that …Dec 18, 2023 · Learn the differences between detention and retention ponds, two methods of managing stormwater runoff. Find out how they work, what they cost, and how they affect the environment and property value. Feb 1, 2020 · 8 Advantages and Benefits of Retention Ponds. Retention ponds improve water quality. Remove pollutants and sediments. Serve as storage facility for controlled release of water. Diminish the threat of flooding. Enhances the Environment and wildlife. Easy to construct and maintain if adequate space is available or provided. Water diversion becomes more important as communities expand. Stormwater runoff overflows city sewage systems and can erode surrounding streams and rivers, damaging nature [1]. Stormwater management is the practice of managing and minimizing the effects of stormwater runoff to maintain water quality, reduce flooding, and …POND DESIGN EXAMPLE. The following design example is for the "wet extended detention (ED) pond," from STP Group 1 (stormwater ponds). On this site the developer is required to provide control for the following: Recharge (Based on soil type) Water Quality (90% event) Channel Protection. 10-year Flood Control. Safe Passage of the 100-year …The main difference is the purpose of the pond. Retention ponds are designed to hold water, while detention ponds are designed to detain water and release it slowly over time. Another key difference is the depth of the pond. Retention ponds are usually shallow, while detention ponds are usually deep. Finally, retention ponds …What is a Detention Pond? The main difference between a detention and a retention pond is whether or not it has a permanent pool of water. A detention pond is designed as a ^dry pond. Its purpose is to hold back flood waters and slowly release the water so that creeks and rivers do not become flooded. Are the ity of uda’s Retention ...An Amex retention offer may initally appear outstanding, but traps exist. Here's what to think over prior to accepting one. Increased Offer! Hilton No Annual Fee 70K + Free Night C...Having a pond in your backyard can be a great way to add beauty and value to your property. But before you start digging, it’s important to understand the hidden costs associated w...15.3 Retention or Detention Areas 15.3.1 Pond Detail Sheet The retention or detention pond, including the outlet structure, is usually the end point of the drainage system for a particular project. The retention/detention pond detail sheet must show the pond in plan view, with station and offset ties to the project centerline of construction.A first-of-its-kind computer-based model for designing smaller catchments will help stormwater experts deal with rapid development. The model, dubbed SUDS (Simplified Urban Detention System), cuts detention pond design time to just minutes. Piloted with success in Greenville County, SC, SUDS allows users with watershed data to design …Learn the difference between detention and retention ponds, two types of stormwater basins that control flood flows and water quality. Find out the advantages, disadvantages and …They may look like regular ponds, but if you look a little bit closer, you can usually tell the difference between a retention pond and a regular pond. Detention ponds, for instance, have steep sides and usually aren’t meant for swimming or recreational activity. These ponds serve as a collection and storage place for stormwater to drain into. retention vs. detention A retention pond does not discharge to a downstream system. The only way water leaves a retention pond is by evaporation or by soaking into the surrounding soils. A detention pond discharges into a drainage system, usually through an underground pipe. The majority of ponds in the City of Everett are designed to be ... Okiryun Yes, the civil engineers try to construct dry retention ponds on all sites in the panhandle of Florida. Retention ponds directly infiltrate the stormwater into the shallow unconfined aquifer. When clayey soils are present at the surface, we will recommend a vertical sand chimney to key into deeper sand layers.Retention Pond vs. Detention Pond. Since a retention pond may be referred to as a wet detention pond, be careful not to confuse it with a detention pond or detention basin. Detention ponds are also known as dry ponds. This is a clue to the primary difference between the two stormwater management ponds: A retention pond …Feb 27, 2015 · Two types of detention and retention stormwater BMPs are dry ponds and wet ponds, respectively. Dry ponds, as the name suggests, are usually dry except during or after rain or snow melt. They are meant to slow down stormwater flow and keep it for a short period of time. Urban locales rely on dry ponds to minimize peak stormwater runoff levels. 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. In response to a storm, the pond’s water level fluctuates, reducing risk and saving the community from potential flood damage ... Jan 18, 2018 ... Slopes of retention ponds need to be checked for erosion at least once per year, and more frequently if the season has been unusually wet. In ...retention pond construction. Correct compaction, particularly around emergency spillways, discharge pipes and anti-seep collars, will keep the system robust. DESIGN - SIZE OF THE POND Calculate the volume of the sediment retention pond using the depth measured from the base of the sediment retention pond to the top of the primary spillway.Maintenance makes them work. To operate successfully, both detention ponds and retention ponds require regular maintenance. Inspections, debris removal, vegetation management, bank stabilization, and structural checks are essential to ensure detention and retention ponds are ready to do their jobs …Mar 23, 2021 · Detention vs. Retention Stormwater Ponds: The Water Rights Implications. There are two types of stormwater ponds: detention ponds and retention ponds.Detention ponds only detain water for a short period of time, then release the water to a natural watercourse, while retention ponds retain the water for an indefinite period of time. Video | Draft Extended Detention Basins Fact Sheet | Draft Retention Ponds & Constructed Wetland Ponds Fact Sheet. Video | Draft Upfront Sections. Draft Extended Detention Basin Figures. Stakeholder Comment Form. Meetings. 3/31/2022 – Draft Fact Sheet Q&A. 8/6/2020 – EDBs, RPs, and CWPs. Video | Meeting Minutes. Supporting …Detention Basins 7.47V 0.78 U U Brown and Schueler, 1997b Retention Basins 1.06V: 0.25 acre retention basin (23,300 cubic feet) U SWRPC, 1991 0.43V: 1.0 acre retention basin (148,000 cubic feet) 0.33V: 3.0 acre retention basin (547,000 cubic feet) 0.31V: 5.0 acre retention basin (952,000 cubic feet) Notes V refers to the total basin volume in ... Retention is primarily provided on the surface through ponds, and underground through tanks, more commonly geocellular tanks. Detention is often provided by detention basins. Retention storage within ponds as well as helping manage flood risk is also useful in providing water treatment. However, there should be upstream components or treatment ... The difference between a detention basin and a retention pond is the existence of a permanent pool, i.e., the former does not have a permanent pool, whereas the latter (being wet ponds) does have a permanent pool. The performance results in retention ponds are more different from the OLS results than those in detention basins.retention vs. detention A retention pond does not discharge to a downstream system. The only way water leaves a retention pond is by evaporation or by soaking into the surrounding soils. A detention pond discharges into a drainage system, usually through an underground pipe. The majority of ponds in the City of Everett are designed to be ...Water Quality Issues. Stormwater detention pond is meant to improve the water quality from non-point sources during rainstorm and not for point sources pollution. Pollutants and sediments that are excessively accumulated in the pond, can be carried downstream in large plumes causing major water quality issues during large flood event.If you are planning to create a beautiful pond in your garden, one of the most crucial decisions you’ll need to make is choosing the right pond liner. A pond liner not only helps t...May 25, 2022 ... Best management practices if you have a detention basin or retention pond on your property. Watch Our Live Streams! Lex TV 185 Lexington, ...Detention ponds can lessen the erosion of downstream channels during flood events (Ravazzani ... basins, focussing on lessening the impact on the environment. Saragih et al. found optimal locations for retention ponds in the form of a suitability map, using a GIS-based MCDM technique to analyse seven factors (rainfall, runoff, slope ...Detention Ponds. Detention ponds are commonly used in areas where there is at least 10 acres of land available. They have a slight slope to help redirect water into the drainage system, while the basin area can retain a large amount of water. Once in the detention pond, the water slowly drains out through the structure’s bottom.As you can see, the post-development increased the Peak runoff rate to 79 cfs from 36 cfs in its natural state. Our goal now is to design a detention pond that will produce an outflow hydrograph that looks similar to the pre-developed (red) hydrograph for the 2, 10 and 100-year events. Design Your Detention Pond The Guidebook provides a technical resource for both Phase I and Phase II NPDES communities. This Guidebook provides the inspector, program manager, designer, and owner (i.e., responsible party) with an understanding of common stormwater pond and wetland maintenance problems and possible solutions. Since the 1970s, stormwater detention has been widely accepted as an effective means to reduce the developed peak flow to its historical rate. A detention basin is often designed as a regional flood control facility to reduce the 10- and 100-year runoff releases. Figure 1. Detention Basin Click here to enlarge image.Therefore, you can think of the retention basin as holding one or more batches of stormwater. Of course, like detention ponds, not all storms are retained.Learn the difference between detention ponds and retention ponds, why they are needed, and how they are designed. Detention ponds reduce flooding by storing rainwater temporarily, while retention ponds hold water indefinitely as a feature.A detention facility may be designed to contain a permanent pool of water. The use of a dry-bottom detention pond is recommended for an INDOT project. Because most of the design procedures are the same for a wet- or a dry-bottom detention facility, the term storage facility will be used in this Chapter to mean either. 2. Retention. A retention ...Therefore, you can think of the retention basin as holding one or more batches of stormwater. Of course, like detention ponds, not all storms are retained.We wanted to share this great info to help stormwater pond owners in Charlotte, Asheville, Greenville, and Spartanburg understands what their responsibilities and how stormwater ponds function. What are wet and dry ponds? A pond is a type of stormwater management facility designed to collect rainwater and pollutants and prevent …DESCRIPTION. Wet detention ponds are storm water control. structures providing both retention and treatment of. contaminated storm water runoff. A typical wet. detention pond design is shown in Figure 1. The. pond consists of a permanent pool of water into. which storm water runoff is directed.Retention is primarily provided on the surface through ponds, and underground through tanks, more commonly geocellular tanks. Detention is often provided by detention basins. Retention storage within ponds as well as helping manage flood risk is also useful in providing water treatment.Detention ponds can lessen the erosion of downstream channels during flood events (Ravazzani ... basins, focussing on lessening the impact on the environment. Saragih et al. found optimal locations for retention ponds in the form of a suitability map, using a GIS-based MCDM technique to analyse seven factors (rainfall, runoff, slope ...Okiryun Yes, the civil engineers try to construct dry retention ponds on all sites in the panhandle of Florida. Retention ponds directly infiltrate the stormwater into the shallow unconfined aquifer. When clayey soils are present at the surface, we will recommend a vertical sand chimney to key into deeper sand layers.Feb 15, 2024 · A retention pond is an artificial pond that serves as a key element in stormwater management. Designed to manage excess rainfall, these ponds act by capturing and holding stormwater runoff. This process helps in mitigating the risks of flooding by controlling the flow of water during heavy precipitation events. The retention ponds hold the ... The primary difference between a detention pond and a retention pond is whether or not the location contains a permanent body of water like most ponds you may be familiar …Detention vs. Retention Detention. Also referred to as dry ponds, detention ponds mainly offer flood control by controlling the rate of water flow. This is accomplished through a control device typically placed at the entrance to the outlet pipe that maintains the pre-development rate of flow. ... Both detention and retention ponds are …Key Differences. Retention and detention ponds are critical structures for managing stormwater, but they serve different purposes and have distinct features. Let's explore the key differences between them: Water Presence - A retention pond has a permanent pool of water where a detention pond is a …Feb 27, 2015 ... Two types of detention and retention stormwater BMPs are dry ponds and wet ponds, respectively. Dry ponds, as the name suggests, are usually ...A first-of-its-kind computer-based model for designing smaller catchments will help stormwater experts deal with rapid development. The model, dubbed SUDS (Simplified Urban Detention System), cuts detention pond design time to just minutes. Piloted with success in Greenville County, SC, SUDS allows users with watershed data to design …What is a Detention Pond? The main difference between a detention and a retention pond is whether or not it has a permanent pool of water. A detention pond is designed as a ^dry pond. Its purpose is to hold back flood waters and slowly release the water so that creeks and rivers do not become flooded. Are the ity of uda’s Retention ...Feb 15, 2024 · A retention pond is an artificial pond that serves as a key element in stormwater management. Designed to manage excess rainfall, these ponds act by capturing and holding stormwater runoff. This process helps in mitigating the risks of flooding by controlling the flow of water during heavy precipitation events. The retention ponds hold the ... Calculation procedures for detention ponds Detention Pond Routing Basics How the Storage-Indication method works and how to troubleshoot pond routings Stage Storage Calculations Contours, Trapezoids and Underground Chambers Stage Discharge Calculations Culverts, Orifices and Weirs Sloped ...Having a pond in your backyard can be a great way to add beauty and tranquility to your outdoor space. But before you start digging, it’s important to understand the cost of buildi...Retention and Detention ponds are the most common solution to managing and controlling storm water runoff in developing areas where significant construction has replaced the absorbable ground surface with concrete, asphalt and other impermeable surfaces. In basic terms, the less ground area there is for water absorption, the more prone that ...governing wet detention ponds. The location and use of wet detention ponds may be limited by regulations relating to stormwater management, navigable waters (Ch. 30, Wis. Stats.), floodplains, wetlands, buildings, wells and other structures, or by land uses such as waste disposal sites and airports. The pond embankment may be The largest advantage of detention ponds are the cost efficiency. They are essentially large holes in the ground and can remain that way until a large storm. Similar to retention ponds, however, a large disadvantage to these ponds is that they require a lot of space to be useful. Detention ponds also can’t contribute to water retention ... The retention pond has a permanent pool of water that fluctuates in response to precipitation and runoff from the contributing areas. Maintaining a pool discourages resuspension and keeps deposited sediments at the bottom of the holding area. Detention Ponds. Detention ponds are more common in the arid west and serve as …Retention Pond vs. Detention Pond. Since a retention pond may be referred to as a wet detention pond, be careful not to confuse it with a detention pond or detention basin. Detention ponds are also known as dry ponds. This is a clue to the primary difference between the two stormwater management ponds: A retention pond …With people carrying little or no cash, Tippy provides employee retention through a digital tipping solution for service industry businesses. * Required Field Your Name: * Your E-M...Wet Pond. Wet Pond, sometimes called a retention pond, is a stormwater management facility which controls the water discharge before releasing it to the stream and retains a certain depth of water in the …Deep pools of water, micropools, and shallow marshes, are three common types of retention ponds. More information on this Green Infrastructure Practice can be ...Abiotic factors of a pond are all elements that are in or that affect the ecosystem of a pond other than the living, or biotic, factors. Some abiotic factors may be suspended in th...The intent of this arrangement is generally to store all the inflow until the pond level reaches the weir or other overflow device. Any excess volume will flow over the weir and continue downstream. As the inflow subsides, the storage may be emptied by exfiltration, and/or a low-flow outlet device. To avoid the complexity of using two ponds ...A detention pond is a type of infrastructure designed to manage and control stormwater runoff. Its primary function is to collect excess stormwater during periods of heavy rainfall, which helps prevent flooding and mitigates the effects of erosion in downstream waterways. By temporarily holding the water, these ponds play a critical …Feb 1, 2020 · 8 Advantages and Benefits of Retention Ponds. Retention ponds improve water quality. Remove pollutants and sediments. Serve as storage facility for controlled release of water. Diminish the threat of flooding. Enhances the Environment and wildlife. Easy to construct and maintain if adequate space is available or provided. Detention ponds are constructed for flood events and have shorter settling and retention times than retention basins. A retention basin stores water year-round, and the outfall structure contains an orifice at a higher elevation compared to a detention pond. In Ohio, we primarily see retention ponds surrounding developments due to the higher ...Description. Detention basins are surface storage basins or facilities that provide flow control through attenuation of stormwater runoff. They also facilitate some settling of particulate pollutants. Detention basins are normally dry and in certain situations the land may also function as a recreational facility. Retention ponds have flow orifices above the pond’s bottom. Operators place the flow orifice at the desired depth level when flooding is not occurring. Similarly, to how detention ponds work, when water levels in a retention pond are higher than the flow orifice, water flows out until the pond reaches its normal level. Retention Pond Vs. Detention Pond. Artificial water basins or ponds can be classified into two; retention ponds and detention ponds. The main difference between these two types of ponds lies in ...Stormwater wet detention ponds (hereafter “detention ponds”) are implemented to mitigate impacts of urban stormwater runoff on downstream waterbodies. We evaluated the effectiveness of detention ponds in providing this protection by quantifying hydrological, chemical, and biological responses in urban depressional …A detention facility may be designed to contain a permanent pool of water. The use of a dry-bottom detention pond is recommended for an INDOT project. Because most of the design procedures are the same for a wet- or a dry-bottom detention facility, the term storage facility will be used in this Chapter to mean either. 2. Retention. A retention ...The primary alternative to an underground storm water detention structures is an aboveground wet detention pond. While construction costs for ponds are generally lower than for underground storage units (ponds can cost between $17.50 and $35 per cubic meter of storage area [Center for Watershed Protection, 1998]), land used for a surface …Having a pond in your backyard can be a great way to add beauty and tranquility to your outdoor space. But before you start digging, it’s important to understand the cost of buildi...Retention money, according to BusinessDictionary.com, is payment for a service that is withheld until the completion of a condition, usually until all conditions are met by the buy... Retention ponds and detention ponds are two of the types of stormwater ponds commonly constructed. Retention ponds are supposed to be dry until a significant storm event occurs. Stormwater gradually leaves the retention pond by infiltration into the soils and by evaporation. Retention ponds are used in locations where the high ground water table Pond BMP types are grouped into three categories: 1) dry detention basins including extended detention basins, 2) wet basins including both retention ponds and wetland ponds, and 3) infiltration basins. This volume provides specific design criteria for stormwater treatment by these types of BMPs along with generalized construction, and ...
Wet Pond. Wet Pond, sometimes called a retention pond, is a stormwater management facility which controls the water discharge before releasing it to the stream and retains a certain depth of water in the …. Dade library
These ponds prevent downstream flooding and allow sediment, nutrients, heavy metals, and other pollutants, to settle out. Deep pools of water, micropools, and shallow marshes, are three common types of retention ponds. More information on this Green Infrastructure Practice can be found in the Stormwater Management Manual. GIP-06 Extended Detention Wet ponds (also referred to as stormwater ponds, wet retention ponds, or wet extended detention ponds) are constructed basins that have a permanent pool of water throughout the year (or at least throughout the wet season). The primary pollutant removal mechanisms are sediment settling and pollutant uptake, particularly of nutrients, through ... 8 Advantages and Benefits of Retention Ponds. Retention ponds improve water quality. Remove pollutants and sediments. Serve as storage facility for controlled release of water. Diminish the threat of flooding. Enhances the Environment and wildlife. Easy to construct and maintain if adequate space is available or provided.The primary difference between a detention pond and a retention pond is whether or not the location contains a permanent body of water like most ponds you may be familiar …Detention ponds can lessen the erosion of downstream channels during flood events (Ravazzani ... basins, focussing on lessening the impact on the environment. Saragih et al. found optimal locations for retention ponds in the form of a suitability map, using a GIS-based MCDM technique to analyse seven factors (rainfall, runoff, slope ...The difference in detention and retention basins is depicted in Figure 28.56.020. The words “pond” and “basin” may be used to refer to reservoirs that remain dry outside of storm events, ... A retention pond (RP) is a sedimentation facility designed to …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. In response to a storm, the pond’s water level fluctuates, reducing risk and saving the community from potential flood damage ...Retention Pond vs. Detention Pond. Since a retention pond may be referred to as a wet detention pond, be careful not to confuse it with a detention pond or detention basin. Detention ponds are also known as dry ponds. This is a clue to the primary difference between the two stormwater management ponds: A retention pond …May 28, 2009 · Detention (dry) basin. The main difference between a detention and a retention basin is whether or not it has a permanent pool of water – like a traditional “pond”. The water level is established by the low flow orifice. Most of the time the orifice is part of a metal or concrete structure called a riser. We wanted to share this great info to help stormwater pond owners in Charlotte, Asheville, Greenville, and Spartanburg understands what their responsibilities and how stormwater ponds function. What are wet and dry ponds? A pond is a type of stormwater management facility designed to collect rainwater and pollutants and prevent …Lectures have long been a staple in educational settings, providing a platform for knowledge dissemination and learning. However, not all lectures are created equal when it comes t...Retention ponds are bodies of water that are used to store and release water over time, either naturally or artificially. They can be used to regulate water flow, reduce flooding and erosion, and filter pollutants from stormwater runoff. There are several types of retention ponds, each with its own purpose and design.The difference between a detention basin and a retention pond is the existence of a permanent pool, i.e., the former does not have a permanent pool, whereas the latter (being wet ponds) does have a permanent pool. The performance results in retention ponds are more different from the OLS results than those in detention basins.Retention ponds are designed to stay at least partially filled at all times throughout the year. Water levels may fluctuate between the seasons, but the pond won’t completely dry out unless there are unusual conditions like a severe drought. In contrast, detention ponds dry out regularly between seasonal patterns of heavy rainfall. These ...This, coupled with our deep manpower and equipment resources, means American Paving can develop a full range of detention and retention ponds. 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. Detention ponds (dry ponds) and retention ponds (wet ponds) are two different types of water management ponds. In summary, both ponds aid in flood control and stormwater runoff treatment. They collect excess water and hold it for a period of time to help control erosion and water quality. Sediment and bacteria, metals, nutrients, and other ... DESCRIPTION. Wet detention ponds are storm water control. structures providing both retention and treatment of. contaminated storm water runoff. A typical wet. detention pond design is shown in Figure 1. The. pond consists of a permanent pool of water into. which storm water runoff is directed.Jan 18, 2018 ... Slopes of retention ponds need to be checked for erosion at least once per year, and more frequently if the season has been unusually wet. In ...11.5.1 General Considerations: Stormwater Retention vs. Detention 11-25 . 11.5.2 BMP Sizing Using the VRRM Treatment Volume 11-26 . ... For Retention Storage 11-45 . Virginia Stormwater Management Handbook, Chapter 11 July 2013 . 11-3 . Equation 11.17 Load Reduction Requirements for RedevelopmentMay 10, 2021 · A retention pond — sometimes referred to as a “wet pond,” “retention basin,” or “wet detention basin” — is a pond that holds stormwater runoff permanently. Similar to a dam, it’s a means to “contain” and “hold” runoff, allowing water to build up on site. As rainwater falls to the ground, it navigates its way to one of ... .