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Status and Trends: Stormwater Ponds

Written on: May 27th, 2021 in Wetland Assessments

By Alison Rogerson, Wetland Monitoring and Assessment Program (WMAP)

In March we shared some results about the status of wetland acreage in Delaware between 2007 and 2017. This time we’re taking a closer look at the increasing number of stormwater ponds popping up across the state. Is this a good trend or something to be concerned about? How do ponds relate to wetland health?

You pass stormwater ponds every day. Along State Highway Route 1, next to the shopping center parking lot, or at the entrance of your neighborhood. Stormwater ponds are ubiquitous with development and we have a lot of development in Delaware.

Photo Credit: Environmental Protection Agency

In fact, between 2007 and 2017 Delaware experienced an increase of 1,260 acres of man-made retention or stormwater ponds around housing developments, ponds in industrial areas, or agricultural ponds. This represents 81% of all the acres of wetlands created, or gained, in this time period. The majority of open water gains occurred in Sussex County.

What is the issue with building more stormwater ponds and what does it have to do with wetlands? It just so happens that at the same time Delaware gained 1,260 acres of open water ponds, it lost 655 acres of freshwater wetlands, mostly forested, to development. In many cases, forested freshwater wetlands were lost to development and new developments require stormwater management, often as ponds.

Photo Credit: DelDOT

Unfortunately, created ponds do not function the same way natural, forested wetlands do. Man-made open water ponds offer stormwater holding capacity, but don’t offer the same filtration and slow release into natural waterways that floodplain wetlands do. Stormwater ponds can be used by generalist wildlife species such as red-winged blackbirds or mallards, but do not offer the specialized habitat qualities that Delaware’s wetlands can provide. Created ponds offer little in the way of plant community, often cattails or the invasive Phragmites, whereas natural wetlands provide a rich array of beneficial plants.

I wish I could say this trend of increasing stormwater ponds and decreasing wetlands was just a recent occurrence, but similar changes were observed in previous decades as well. According to our previous statewide mapping update and analysis done for 1992-2007, gains in ponds exceeded gains of any other wetland type by 115%.

Do we need stormwater ponds? Yes. Especially as weather patterns become more extreme, bringing heavy rain events upon us in Delaware, we need infrastructure to quickly handle flash events and heavy stormwater loads. Stormwater management keeps our roads and neighborhoods from flooding, and can prevent backups that lead to polluted waters being released.

However, it is not appropriate to replace natural wetlands with stormwater ponds in the name of development. The trade-off in functions and natural services does not add up. In addition, stormwater infrastructure has been modernized to more naturally offer storage and filtration services that are visually appealing.

Green stormwater infrastructure features can be planted with native trees and shrubs and may sit dry until a storm event. These structures are still ready and waiting to hold and manage storm events, but allow the soil and plants to play a beneficial role. Bioretention gardens are smaller features that can be incorporated into landscaping that are enjoyable to look at.

For more information on Green Stormwater Infrastructure visit this USGS webpage.


WATAR you up to?

Written on: May 17th, 2021 in Wetland Restorations

By Maggie Pletta, DNREC Coastal, Climate and Energy Delaware is known for many things… like being first, Joe Biden, and horseshoe crabs. However, there are a few less flattering things that Delaware is known for, and one is a history of polluted waterways. A large number of Delaware’s waterbodies have a fish consumption advisory, with […]

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American Wetlands Month: 5 Reasons to Love Wetlands

Written on: May 17th, 2021 in Outreach

By Olivia McDonald, Wetland Monitoring and Assessment Program (WMAP) Happy American Wetlands Month! During the month of May we celebrate the incredible importance of wetlands to the environment and humans alike. Wetlands are ranked as one of Earth’s most productive ecosystems, supporting an incredible amount of biodiversity, and are considered a nature-based solution to climate […]

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Chesapeake Adventures: Exploring Wetland Condition in the Chester-Choptank Watershed

Written on: May 17th, 2021 in Wetland Assessments

By Erin Dorset, Wetland Monitoring & Assessment Program (WMAP) Here at the Wetland Monitoring & Assessment Program (WMAP), most fieldwork is done in the Delaware Bay and Inland Bays drainage basins, where waters move east to the Delaware Bay and the Atlantic Ocean. But, in 2018, WMAP had the opportunity to perform wetland assessments in […]

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Living Shoreline Permitting Do’s and Don’ts

Written on: March 22nd, 2021 in Living Shorelines

By Kenny Smith, Wetland Monitoring and Assessment Program (WMAP) When discussing living shorelines, you might not think the hardest and most unclear part would be getting your permits to accomplish this work. The permit process is sometimes difficult to navigate and can be confusing to someone not immersed in the environmental field. We decided to […]

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Updating the Delaware Wetland Program Plan for 2021-2025

Written on: March 22nd, 2021 in Wetland Assessments

By Alison Rogerson, Wetland Monitoring and Assessment Program (WMAP) What is a state wetland program plan? Delaware creates five-year wetland program plans to serve as a guide that identifies and prioritizes areas where information or action is needed to advance wetland management statewide. It is created using the goals of many different wetland players across […]

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Sea-level Rise, Marsh Migration, and Coastal Resilience

Written on: March 22nd, 2021 in Wetland Restorations

Guest Student Writer: Ezra Kottler, The George Washington University All over the world, sea-level rise is driving changes in natural habitats. Greenhouse gas emissions have brought about the warming of oceans and melting of glaciers such that global mean sea level is increasing over time and the rate at which it increases is getting steeper […]

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Wetland Acreage Status in Delaware

Written on: March 22nd, 2021 in Wetland Assessments

By Erin Dorset, Wetland Monitoring and Assessment Program (WMAP) Back in December, WMAP introduced you to DNREC’s new 2017 wetlands maps. Since then, WMAP has been hard at work finalizing a report detailing the status and trends of wetlands throughout the State of Delaware. Soon, the entire report will be available, but in the meantime, […]

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Can I and Should I Build a Living Shoreline…

Written on: December 9th, 2020 in Living Shorelines

By Kenny Smith, Wetland Monitoring & Assessment Program The Delaware Living Shorelines Committee members are often asked questions by landowners. Many of those questions relate to the suitability of their property for a living shorelines project. For example: is it possible to build a living shoreline on their property? Can a living shoreline protect their […]

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Beneficial Reuse of Dredge Material: Rebuilding a Former Tidal Wetland

Written on: December 9th, 2020 in Beneficial UseWetland Restorations

By Erin Dorset, Wetland Monitoring & Assessment Program The Mid-Atlantic is a sea-level rise hotspot, meaning that rates of sea level rise in the region are relatively high. As such, scientists, outdoor enthusiasts, and coastal communities alike are all worried about the fate of tidal wetlands. Here at Delaware’s WMAP, we’re seeing what we can […]

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Delaware Wetland Management & Assessment Program