The document summarizes a presentation on the need for and benefits of a stormwater management bylaw in Sterling, MA. It discusses how typical post-development conditions increase runoff and reduce infiltration, harming water resources. A bylaw is needed to require stormwater permits and low impact development techniques to minimize these impacts. The Sterling bylaw aims to protect water quality, maintain pre-development hydrology, and ensure stormwater structures function properly. It encourages simple, non-structural methods and exempts small residential projects.
The document discusses changing stormwater regulations in Connecticut. Municipalities are increasingly requiring low impact development (LID) techniques to reduce stormwater pollution from development. LID aims to reduce impervious surfaces and runoff volumes to lower pollutant loads through techniques like bioretention basins, narrower roads, and permeable pavement. The document provides examples of LID projects and maintenance best practices to meet water quality goals and comply with new regulations.
The document discusses the Coon Creek Watershed District and its roles and responsibilities. It describes what a watershed is, defines a watershed district as a special purpose local government, and outlines Coon Creek's mission to prevent property damage, maintain hydrologic balance, and protect water quality for citizens and wildlife. It also discusses the district's ditch system, property rights and easements, management of outlots, and roles in regulating development and maintaining drainage infrastructure.
Sustainable urban drainage systems (SUDS) provide a natural approach to managing drainage around developments. SUDS slow and hold back rainwater and runoff from impervious surfaces like roads and buildings. This allows the water to be purified as it is held in wetland environments on site. The purified water is then slowly released into local waterways to prevent contamination. SUDS also increase biodiversity by creating habitats like ponds and wetlands that attract various wildlife.
The document discusses green infrastructure as both a planning approach and stormwater management approach. As a planning approach, green infrastructure creates an interconnected network of natural areas that provides ecosystem services and benefits. As a stormwater management approach, it refers to systems that mimic natural processes to infiltrate, evapotranspirate, or reuse stormwater on-site. The document then provides examples of specific green infrastructure technologies and their stormwater management benefits, such as rain gardens capturing 30-80% of rainfall and reducing pollutants. Overall, the green infrastructure approach treats stormwater at its source, unlike traditional approaches that focus on rapid removal.
This presentation notes that in economic terms flooding is the major natural disaster experience in Trinidad and discusses the lack of sustainability of the current approach to drainage and flood mitigation and proposes some solutions such as storm water management at source as a possible solution to flooding
The document discusses changing stormwater regulations in Connecticut. Municipalities are increasingly requiring low impact development (LID) techniques to reduce stormwater pollution from development. LID aims to reduce impervious surfaces and runoff volumes to lower pollutant loads through techniques like bioretention basins, narrower roads, and permeable pavement. The document provides examples of LID projects and maintenance best practices to meet water quality goals and comply with new regulations.
The document discusses the Coon Creek Watershed District and its roles and responsibilities. It describes what a watershed is, defines a watershed district as a special purpose local government, and outlines Coon Creek's mission to prevent property damage, maintain hydrologic balance, and protect water quality for citizens and wildlife. It also discusses the district's ditch system, property rights and easements, management of outlots, and roles in regulating development and maintaining drainage infrastructure.
Sustainable urban drainage systems (SUDS) provide a natural approach to managing drainage around developments. SUDS slow and hold back rainwater and runoff from impervious surfaces like roads and buildings. This allows the water to be purified as it is held in wetland environments on site. The purified water is then slowly released into local waterways to prevent contamination. SUDS also increase biodiversity by creating habitats like ponds and wetlands that attract various wildlife.
The document discusses green infrastructure as both a planning approach and stormwater management approach. As a planning approach, green infrastructure creates an interconnected network of natural areas that provides ecosystem services and benefits. As a stormwater management approach, it refers to systems that mimic natural processes to infiltrate, evapotranspirate, or reuse stormwater on-site. The document then provides examples of specific green infrastructure technologies and their stormwater management benefits, such as rain gardens capturing 30-80% of rainfall and reducing pollutants. Overall, the green infrastructure approach treats stormwater at its source, unlike traditional approaches that focus on rapid removal.
This presentation notes that in economic terms flooding is the major natural disaster experience in Trinidad and discusses the lack of sustainability of the current approach to drainage and flood mitigation and proposes some solutions such as storm water management at source as a possible solution to flooding
Restoring Natural Drainage System of DelhiIram Aziz
This document discusses the benefits of restoring natural drainage systems in Delhi and the impacts of degrading streams. It provides examples of restoring drainage systems in other cities like San Antonio, Texas and Seoul, South Korea. The Cheong Gye Cheon river restoration project in Seoul is highlighted, which uncovered a buried river and created a public park. The document argues for restoring Delhi's drainage channels by daylighting streams and treating wastewater to create linear parks. It outlines policy principles and a strategy for protecting stormwater channels through a Watershed Management Plan and Urban Drainage Master Plan.
The Green Infrastructure Center helps communities implement green infrastructure solutions to manage stormwater and conserve natural areas. They provide guidance and case studies on using approaches like low impact development, green roofs, rain gardens, and trees to absorb and filter stormwater runoff. Overdevelopment has increased impervious surfaces and the amount of runoff, while reducing natural infrastructure like forests that previously absorbed water. The document discusses the benefits of green infrastructure in reducing flooding and pollution from stormwater while beautifying areas. It provides best practices for retrofitting existing development and incorporating green approaches into new projects.
Gray vs. Green: The Role of Watershed-scale Green Infrastructure Systems for ...Mcrpc Staff
This document discusses the role of green infrastructure systems for managing wastewater at a watershed scale. It begins by outlining the historical patterns of water movement through uplands and lowlands, and how contemporary development has reversed these patterns. It then describes various green infrastructure strategies that can replicate natural hydrology, including green roofs, porous pavements, bio-retention systems, rainwater harvesting, wastewater recycling, and native landscaping. The document provides examples of these strategies and concludes by discussing a new paradigm in wastewater treatment using lagoons and floating mats of bacteria to polish wastewater in a low-cost, low-energy manner.
The document discusses Peoria, Illinois' stream buffer ordinance. It defines a stream buffer as a protective, forested strip of land along both sides of a stream. Benefits of stream buffers include erosion control, flood management, water quality protection, and aesthetic and recreational value. Peoria developed its ordinance due to problems like unstable slopes and floodplain encroachment. The ordinance requires a 30-50 foot vegetated buffer on each side of streams and includes the 100-year floodplain. It allows for traditional compliance with buffer zones or alternative compliance through other conservation methods. The ordinance has led to reforestation of buffer areas and enforcement through fines for violations.
This document provides an overview of sustainable urban drainage systems (SUDS). SUDS are a natural approach to managing drainage in developed areas that aims to mitigate the environmental impacts of conventional drainage systems. The key points covered are:
- SUDS work by slowing water runoff to allow natural processes to break down pollutants through techniques like retention ponds and permeable pavements.
- Conventional drainage causes issues like increased flooding and water pollution, while SUDS seek to maintain natural water cycles and protect water quality.
- Proper design of SUDS considers factors like maintenance needs, constraints of the site, and treating runoff through a "treatment train" approach with controls at different scales.
-
Pinelands Regional Municipal Leaders Green Infrastructure WorkshopNew Jersey Future
This document summarizes a workshop on green infrastructure for municipal leaders in the Pinelands region. It discusses the impacts of increased stormwater runoff from development, including water quality issues and flooding. Regulations that address stormwater management for new development are outlined. The benefits of green infrastructure approaches are presented, including cost savings, aesthetics, and environmental protection. Challenges municipalities face with stormwater are discussed and funding opportunities for green infrastructure projects are mentioned.
This document provides information on sustainable stormwater management. It begins with an introduction on stormwater and the need for management. Examples of stormwater management techniques are then presented, including rain gardens, bioretention areas, vegetated swales, green roofs, and porous pavement. The installation processes for rain gardens and bioretention areas are described in multiple steps. Advantages and disadvantages of stormwater management are listed. The document concludes with references and appendices.
This document provides information on sustainable stormwater management systems. It discusses various systems such as green roofs, pervious surfaces, grassed swales, bioretention areas, and describes their installation processes, advantages, and disadvantages. The document also includes a case study and recommendations to improve stormwater management.
Storm water is not only collected from the roof it's also collected from the roads, footpath, parking, lawns and open spaces etc.. and their is four types from water is collected roof water,surface water,sub-drain and soil drain. And what are the various components for collection are described here.
Urban Stormwater Conditions and the Multiple Benefits of Green Infrastructure...RI_FMA
This document discusses urban stormwater issues in Providence, Rhode Island and the benefits of green infrastructure solutions. Providence faces challenges from aging infrastructure, high percentages of impervious surfaces, and industrial contamination near waterways. Green infrastructure approaches like rain gardens, swales, green roofs, and depaving lots can help address stormwater while providing community benefits like recreation, health, habitat, and economic development. Providence is pursuing green infrastructure projects in parks and vacant lots to manage stormwater and provide multiple benefits. Challenges remain around long-term maintenance of green infrastructure sites and further incentivizing private property owners.
This chapter discusses water resources and issues related to water availability, use, and pollution. It begins by explaining where water comes from and how it is distributed and used. It then discusses current and future water shortages due to overuse and climate factors. Water management strategies like conservation and infrastructure projects are described. The chapter also covers sources and impacts of water pollution including from industry, agriculture, and municipalities. It concludes by discussing regulations and strategies to control water pollution.
This document provides information on stormwater management. It discusses the need for stormwater management to reduce flooding and pollution from surface runoff. It describes various techniques used in rural and urban areas to manage stormwater, including temporary storage methods like detention ponds and infiltration methods like grass filter strips. Effective stormwater management requires expert planning, implementation, and ongoing maintenance. When implemented properly, stormwater management provides flood control and water quality benefits while allowing stormwater to be reused.
The document discusses various low impact development programs in multiple cities that help manage stormwater and protect water resources through the use of green infrastructure. It provides examples of green roofs, permeable pavement, rainwater harvesting, bioretention swales, and other natural drainage systems that have significantly reduced stormwater runoff volumes and peak flows in cities like Chicago, Portland, Seattle, Toronto, and Vancouver. It also discusses the Anacostia Waterfront Corporation in Washington D.C. that has established comprehensive environmental standards for development projects, including innovative stormwater retention requirements.
New Jersey Future and Pinelands Preservation Alliance hosted a workshop teaching communities all about New Jersey Future's New Jersey Green Infrastructure Municipal Toolkit. As part of this event, participants learned how to use the toolkit as a resource to plan, implement, and sustain green infrastructure in their town!
Stormwater management aims to reduce surface runoff from rain and snowmelt by promoting infiltration and replenishing groundwater. It is important in urban areas with many impervious surfaces to prevent flooding and pollution. Traditional methods only moved water away, while modern approaches try to restore natural water cycles through retention basins, infiltration basins, bioswales, green roofs, and low impact development techniques. Calculating surface runoff estimates how much water will flow over an area based on its size, average rainfall, and surface type to help design effective drainage systems.
A presentation about reducing nutrients from stormwater runoff through low-impact development/green infrastructure techniques. Presented by Rich Claytor, engineer with Horsley Witten Group, during the Buzzards Bay Coalition's 2013 Decision Makers Workshop series. Learn more at www.savebuzzardsbay.org/DecisionMakers
The document discusses the national and regional direction of stormwater programs. It summarizes recent EPA activities including a National Research Council report recommending that stormwater programs regulate flow rather than pollutants. The document also outlines EPA's plan to develop consistent stormwater regulations through rulemaking, including establishing post-construction requirements and expanding coverage to additional discharges. Region 4 expects future MS4 permits to include clearer, more specific, and enforceable requirements.
The document discusses stormwater management from a municipal perspective. It summarizes Richmond Hill's efforts to manage stormwater through collaborative initiatives, updating infrastructure, and adopting low impact development practices. Challenges include integrating stormwater management into municipal programs, obtaining public acceptance, and funding maintenance and upgrades, especially with climate change increasing storm intensities.
Restoring Natural Drainage System of DelhiIram Aziz
This document discusses the benefits of restoring natural drainage systems in Delhi and the impacts of degrading streams. It provides examples of restoring drainage systems in other cities like San Antonio, Texas and Seoul, South Korea. The Cheong Gye Cheon river restoration project in Seoul is highlighted, which uncovered a buried river and created a public park. The document argues for restoring Delhi's drainage channels by daylighting streams and treating wastewater to create linear parks. It outlines policy principles and a strategy for protecting stormwater channels through a Watershed Management Plan and Urban Drainage Master Plan.
The Green Infrastructure Center helps communities implement green infrastructure solutions to manage stormwater and conserve natural areas. They provide guidance and case studies on using approaches like low impact development, green roofs, rain gardens, and trees to absorb and filter stormwater runoff. Overdevelopment has increased impervious surfaces and the amount of runoff, while reducing natural infrastructure like forests that previously absorbed water. The document discusses the benefits of green infrastructure in reducing flooding and pollution from stormwater while beautifying areas. It provides best practices for retrofitting existing development and incorporating green approaches into new projects.
Gray vs. Green: The Role of Watershed-scale Green Infrastructure Systems for ...Mcrpc Staff
This document discusses the role of green infrastructure systems for managing wastewater at a watershed scale. It begins by outlining the historical patterns of water movement through uplands and lowlands, and how contemporary development has reversed these patterns. It then describes various green infrastructure strategies that can replicate natural hydrology, including green roofs, porous pavements, bio-retention systems, rainwater harvesting, wastewater recycling, and native landscaping. The document provides examples of these strategies and concludes by discussing a new paradigm in wastewater treatment using lagoons and floating mats of bacteria to polish wastewater in a low-cost, low-energy manner.
The document discusses Peoria, Illinois' stream buffer ordinance. It defines a stream buffer as a protective, forested strip of land along both sides of a stream. Benefits of stream buffers include erosion control, flood management, water quality protection, and aesthetic and recreational value. Peoria developed its ordinance due to problems like unstable slopes and floodplain encroachment. The ordinance requires a 30-50 foot vegetated buffer on each side of streams and includes the 100-year floodplain. It allows for traditional compliance with buffer zones or alternative compliance through other conservation methods. The ordinance has led to reforestation of buffer areas and enforcement through fines for violations.
This document provides an overview of sustainable urban drainage systems (SUDS). SUDS are a natural approach to managing drainage in developed areas that aims to mitigate the environmental impacts of conventional drainage systems. The key points covered are:
- SUDS work by slowing water runoff to allow natural processes to break down pollutants through techniques like retention ponds and permeable pavements.
- Conventional drainage causes issues like increased flooding and water pollution, while SUDS seek to maintain natural water cycles and protect water quality.
- Proper design of SUDS considers factors like maintenance needs, constraints of the site, and treating runoff through a "treatment train" approach with controls at different scales.
-
Pinelands Regional Municipal Leaders Green Infrastructure WorkshopNew Jersey Future
This document summarizes a workshop on green infrastructure for municipal leaders in the Pinelands region. It discusses the impacts of increased stormwater runoff from development, including water quality issues and flooding. Regulations that address stormwater management for new development are outlined. The benefits of green infrastructure approaches are presented, including cost savings, aesthetics, and environmental protection. Challenges municipalities face with stormwater are discussed and funding opportunities for green infrastructure projects are mentioned.
This document provides information on sustainable stormwater management. It begins with an introduction on stormwater and the need for management. Examples of stormwater management techniques are then presented, including rain gardens, bioretention areas, vegetated swales, green roofs, and porous pavement. The installation processes for rain gardens and bioretention areas are described in multiple steps. Advantages and disadvantages of stormwater management are listed. The document concludes with references and appendices.
This document provides information on sustainable stormwater management systems. It discusses various systems such as green roofs, pervious surfaces, grassed swales, bioretention areas, and describes their installation processes, advantages, and disadvantages. The document also includes a case study and recommendations to improve stormwater management.
Storm water is not only collected from the roof it's also collected from the roads, footpath, parking, lawns and open spaces etc.. and their is four types from water is collected roof water,surface water,sub-drain and soil drain. And what are the various components for collection are described here.
Urban Stormwater Conditions and the Multiple Benefits of Green Infrastructure...RI_FMA
This document discusses urban stormwater issues in Providence, Rhode Island and the benefits of green infrastructure solutions. Providence faces challenges from aging infrastructure, high percentages of impervious surfaces, and industrial contamination near waterways. Green infrastructure approaches like rain gardens, swales, green roofs, and depaving lots can help address stormwater while providing community benefits like recreation, health, habitat, and economic development. Providence is pursuing green infrastructure projects in parks and vacant lots to manage stormwater and provide multiple benefits. Challenges remain around long-term maintenance of green infrastructure sites and further incentivizing private property owners.
This chapter discusses water resources and issues related to water availability, use, and pollution. It begins by explaining where water comes from and how it is distributed and used. It then discusses current and future water shortages due to overuse and climate factors. Water management strategies like conservation and infrastructure projects are described. The chapter also covers sources and impacts of water pollution including from industry, agriculture, and municipalities. It concludes by discussing regulations and strategies to control water pollution.
This document provides information on stormwater management. It discusses the need for stormwater management to reduce flooding and pollution from surface runoff. It describes various techniques used in rural and urban areas to manage stormwater, including temporary storage methods like detention ponds and infiltration methods like grass filter strips. Effective stormwater management requires expert planning, implementation, and ongoing maintenance. When implemented properly, stormwater management provides flood control and water quality benefits while allowing stormwater to be reused.
The document discusses various low impact development programs in multiple cities that help manage stormwater and protect water resources through the use of green infrastructure. It provides examples of green roofs, permeable pavement, rainwater harvesting, bioretention swales, and other natural drainage systems that have significantly reduced stormwater runoff volumes and peak flows in cities like Chicago, Portland, Seattle, Toronto, and Vancouver. It also discusses the Anacostia Waterfront Corporation in Washington D.C. that has established comprehensive environmental standards for development projects, including innovative stormwater retention requirements.
New Jersey Future and Pinelands Preservation Alliance hosted a workshop teaching communities all about New Jersey Future's New Jersey Green Infrastructure Municipal Toolkit. As part of this event, participants learned how to use the toolkit as a resource to plan, implement, and sustain green infrastructure in their town!
Stormwater management aims to reduce surface runoff from rain and snowmelt by promoting infiltration and replenishing groundwater. It is important in urban areas with many impervious surfaces to prevent flooding and pollution. Traditional methods only moved water away, while modern approaches try to restore natural water cycles through retention basins, infiltration basins, bioswales, green roofs, and low impact development techniques. Calculating surface runoff estimates how much water will flow over an area based on its size, average rainfall, and surface type to help design effective drainage systems.
A presentation about reducing nutrients from stormwater runoff through low-impact development/green infrastructure techniques. Presented by Rich Claytor, engineer with Horsley Witten Group, during the Buzzards Bay Coalition's 2013 Decision Makers Workshop series. Learn more at www.savebuzzardsbay.org/DecisionMakers
The document discusses the national and regional direction of stormwater programs. It summarizes recent EPA activities including a National Research Council report recommending that stormwater programs regulate flow rather than pollutants. The document also outlines EPA's plan to develop consistent stormwater regulations through rulemaking, including establishing post-construction requirements and expanding coverage to additional discharges. Region 4 expects future MS4 permits to include clearer, more specific, and enforceable requirements.
The document discusses stormwater management from a municipal perspective. It summarizes Richmond Hill's efforts to manage stormwater through collaborative initiatives, updating infrastructure, and adopting low impact development practices. Challenges include integrating stormwater management into municipal programs, obtaining public acceptance, and funding maintenance and upgrades, especially with climate change increasing storm intensities.
Design Criteria
•Water efficient fittings and appliances
•On-site water capture and reuse
•Water supply flow rates optimised to balance required performance and conservation
•Local retention of stormwater runoff, stormwater treatment train with consideration of raingardens, roofgardens and swales
•Wastewater minimised and/or reused; information on water use readily available
•In-house water supply flow rate optimised
•Plumbing system designed for water and energy efficiency
•Site design recognition of local soil and climate conditions and low water use garden design applied.
This document discusses strategies for improving water resource protection in real estate development projects. It promotes an open space design approach that requires conserving at least 60% of project sites as open space. This protects water supplies, habitat and other natural resources while also reducing infrastructure costs. The document provides model zoning regulations and guidelines to implement this approach, including conducting conservation analyses, minimizing impervious surfaces, using low impact development stormwater techniques, and incentivizing permanent land conservation.
The document provides information on GreeNexus Consulting and their services related to sustainability certifications like LEED and Living Building Challenge. It also discusses various codes, standards and resources related to green building certifications, water efficiency and rainwater harvesting.
Urban Planning Design Considerations for Better Water Quality, Bill Hunt NC S...Fu Michael Justin
This document discusses various studies and case studies related to the impacts of development on water quality. It summarizes that effective solutions require maintaining watershed hydrology through low impact development techniques like reducing impervious surfaces, incorporating bioretention areas, and maintaining wetlands and riparian buffers. A case study of the Carpenter Village development showed positive results from using clustered housing, narrow streets, integrated open space and bioretention to minimize impacts on water quality.
Lisa stormcon presentation number one iecaLisa Nisenson
The document discusses new stormwater regulations that require managing stormwater runoff through land use planning and development codes. It covers how concepts like low impact development and smart growth can be incorporated into codes to reduce impervious surfaces. It provides examples of how street design standards, parking requirements, and zoning codes can be updated to better control stormwater runoff from new development.
This document discusses the need for regulatory change to address emerging environmental and societal issues. It provides examples of how public and private stakeholders have worked together to enact regulatory changes. One case study describes how a pilot wastewater reuse project led Massachusetts to develop regulatory guidelines and later formal regulations allowing for expanded uses of reclaimed water. The document advocates for creating flexible regulatory structures through cooperation between regulators and developers.
This presentation was delivered by Dr. Jeremy Carew-Reid, Director General of ICEM at the 5th Greater Mekong Subregion Environment Minister's Meeting in Chiang Mai, Thailand from 30 January to 1 February 2018. The presentation demonstrates how green infrastructure can enhance resilience and sustainability in urban areas and across rural landscapes.
The document discusses implementing an integrated storm water management program for the city of Killeen. It outlines elements of the program including drainage maintenance, capital improvements, and storm water management plans. It also discusses issues driving the need for improved drainage infrastructure maintenance like citizen concerns, water quality and quantity control issues from urbanization. Potential solutions discussed include code revisions, public education, debris removal, inspections, and design/maintenance standards.
Case Study No. 9-Philippines’ Integrated Stormwater Managementharoldtaylor1113
The document discusses stormwater management in the Philippines. It begins by defining stormwater and explaining how stormwater runoff can cause pollution and flooding issues in urban areas without proper management. It then discusses stormwater harvesting, which involves collecting, treating, storing and distributing stormwater for reuse. The key aspects of stormwater harvesting systems are collection, treatment, storage and distribution. Twelve principles for integrating effective stormwater practices into the urban landscape are also outlined. Poor stormwater management can lead to downstream flooding, erosion, turbid waters, habitat destruction and contaminated streams/rivers. The Philippines faces challenges with fragmented water agencies, depletion of water resources, and inadequate infrastructure for managing increasing urbanization pressures.
This document summarizes a case study of balancing wetland and stream preservation with stormwater management for a development project. The initial development proposal impacted wetlands and streams, but these impacts were avoided and minimized through design revisions. Additional mitigation included onsite wetland creation. However, the proposed regional stormwater management ponds could impact water quality in the streams. Alternative approaches were developed that focused on managing stormwater in upland areas before release into waters and wetlands. A monitoring plan was also implemented to evaluate impacts. Through these measures, growth was accommodated while avoiding impacts to resources and maintaining effective stormwater strategies.
Jersey Water Works Green Infrastructure Training at NJ Society of Municipal E...New Jersey Future
The Green Infrastructure Committee of Jersey Water Works presented to the New Jersey Society of Municipal Engineers about green infrastructure on September 14, 2016.
Stormwater management design must adhere to regulations while considering local conditions and infrastructure needs. Effective systems can improve water quality, reduce flooding, and enhance livability through green infrastructure like bioretention and permeable pavements. Challenges include climate uncertainty, limited space, and protecting ecosystems, but well-designed projects showcase stormwater's benefits through beautiful, multi-purpose landscapes.
The Green Building presentation is to introduce regulation and strategies to reduce buildings impacts on the Environment considering water consumption ,energy consumption ,waste generation in addition to building indoor quality, which will be valuable for architects and engineers who interested in LEED accreditation.
Green Building presentation discuss the following aspects
§ Building Environmental impacts
§ Green Buildings Benefits
§ Green building Basic Aspects
A. Sustainable sites
B. Water Efficiency
C. Energy and Atmosphere
D. Materials & Resources
E. Indoor Environmental Quality
The mentioned above aspects cover building selected activities during design and construction
This document discusses flooding challenges in Fairfax County and options to address them. It provides a history of stormwater management in the county from the 1940s to present. It also summarizes significant rainfall events that have impacted the county. The document evaluates options to address flooding for existing development, including enhancing overland relief, improving stormwater conveyance, upsizing systems, upgrading culverts, and property acquisition. It also discusses challenges from redevelopment. The document considers policy issues and provides recommendations, including allowing use of yards and roads for overflow, upsizing pipes to 100-year standards, and encouraging flood insurance. Contact information is provided for more details.
This document discusses green infrastructure and stormwater management programs and policies. It provides an overview of Lynn Richards from the EPA's Smart Growth Program speaking at the Congress for New Urbanism on June 13, 2008 about developing different standards for greenfield development and redevelopment in stormwater permits and recognizing land use strategies that directly benefit water quality. The document outlines examples of better and worse responses to stormwater management and provides details on stormwater credits and applying permits to development projects.
Low impact development (LID) is an approach to land development that emphasizes using small-scale stormwater management practices, green infrastructure, and environmental site design for the purpose of maintaining pre-development hydrologic conditions. The presentation discusses the benefits of LID for residents, developers, communities, and the environment. It outlines five basic principles of LID design and provides examples of entities that have adopted LID standards or are in the process of adopting them. The presentation argues for a mandatory rather than voluntary approach to implementing LID and provides strategies for getting political acceptance and introducing LID requirements through ordinances, standards, and education.
28. Creating a Hydrologically Functional Lot Conservation Open Drainage Rain Gardens Rain Barrel Reduced Imperviousness Porous Pavement Creating a Hydrologically Functional Lot
Editor's Notes
By way of background, here’s a diagram of a typical “water budget” for a piece of land in its natural state. Of all the rain that falls, half of it goes into the ground, and only 10% runs off directly into streams and rivers.
After development, however, pavement and storm sewers work together to collect stormwater and send it into rivers and streams as fast as possible. As a result, more than half of the stormwater runs off into waterways, and only 15% returns to the ground through infiltration.
Looking at these photos, you can see why those runoff and infiltration numbers change so much—lots of asphalt! This is what most current zoning codes require: expansive parking lots and excessively wide streets. How do you know if your street is too wide? If teenagers are doing donuts right in the roadway—see the skid marks in the picture on the left. The places here are designed primarily for the automobile, and as a result they are not particularly friendly to pedestrians, bicyclists, or wildlife. The goal of Low Impact Development is to create multifunctional places are designed for people, wildlife, and cars.
It’s also important to recognize the incredible investment that goes into conventional site work and stormwater management systems: asphalt curbs, catch basins, storm sewers, and detention ponds consume a large proportion of the development budget for most projects. Unfortunately, “end-of-pipe” solutions have a limited effectiveness, because they have to treat huge amounts of runoff. Through good site design and low impact development techniques that deal with stormwater close to the source, developers can improve the environmental impact of their projects while also saving money, resulting in more profit and increased potential for affordable housing.
Now let’s go through six key Low Impact Development Principles. The first and most important principle is to work with the landscape. Rather than imposing a predetermined development formula or cookie cutter approach, LID uses the existing landscape as the framework for site planning. Good site design begins with careful attention to good land use planning at the community level as well as the watershed level, so that the right uses go in the right places with regard to the watershed. In general, a site design should identify important environmental resources and should define a development envelope where new housing or business can be placed with minimal impact on those resources. Those resources might include legally protected wetlands, aesthetically important features such as mature trees or good vistas, and hydrologic features such as permeable soils and drainageways.
Our second key principle is to focus on prevention, not mitigation. The goal is to work with the site characteristics to maintain hydrologic functions and processes rather than attempt to mitigate impacts of alteration. For example, avoiding the disturbance and grading of vegetated areas can significantly reduce the need for stormwater controls and will help to recharge groundwater. Designers can also reduce the amount of impervious surface and associated runoff by reducing road widths, clustering buildings and using permeable surfaces for parking. Road alignment is important as well—designers should consider ways to reduce the total road length, and to place the roads to minimize the amount of cut and fill necessary. Green rooftops can also be used to reduce the amount of runoff from buildings. The photo on the slide shows a residential site where a forested area has been preserved, roof runoff is directed to vegetated areas where it will infiltrate, and the road is placed close to the house to minimize the length of the driveway.
Conventional stormwater systems treat stormwater at the “end of the pipe” in large detention ponds design to treat large volumes of runoff. In contrast, Low Impact development strategies use small, decentralized techniques to treat stormwater runoff close to where it is created. The site is designed and graded to create many small drainage areas, and the runoff from each of these subwatersheds is treated through nearby LID structures. LID techniques are commonly designed in series; for example, runoff might flow over a filter strip, into a vegetated swale, which leads to a bioretention cell. This “treatment train” approach provides excellent stormwater management because each of the techniques helps to remove pollutants, allow infiltration, and slow down the runoff to reduce peak discharge rates. In contrast to the conveyance goals of storm sewers, site designs that create long flow paths and low slopes help to reduce runoff rates and increase groundwater infiltration. Finally, it is important to remember that LID techniques are excellent strategies for controlling peak discharge rates from frequent, low-intensity storms, and they can usually be sized to accommodate the entire “water quality volume”—the first inch or half-inch that must be treated according to the Massachusetts Stormwater Policy. However, on sites with large amounts of impervious surfaces, it is likely that additional controls may be needed to manage the runoff from very large storms, such as the 25-year or 100-year storm. However, these controls will be considerably smaller than they would be otherwise.
While LID strategies must be carefully selected and implemented, it is important to remember that many of these techniques are very simple, almost common sense approaches to dealing with stormwater. So-called “open drainage systems” such as vegetated swales cost considerably less than conventional curb and catch basin designs, but they provide better water quality treatment and improve the appearance of a site. Property owners and developers can also reduce the amount of runoff in the stormwater system by directing rooftop runoff to vegetated areas where it will infiltrate or into low-cost rain barrels and cisterns where it can be used for infiltration, saving money on water bills. In the photo here, a rooftop downspout is directed to a vegetated area where it will infiltrate into the ground. One of the most effective methods of improving water quality is frequent street sweeping and parking lot sweeping. Finally, it is very important to reduce site disturbance during construction. The clearing, grading, and compaction that occurs during development can severely reduce the capacity of soils to hold and infiltrate stormwater. Developers should define a disturbance envelope that is as small as possible, and when construction is complete they should try to restore disturbed areas. Builders can help to restore the storage and infiltration capacity of compacted soils by roto-tillling them before seeding. Even better, disturbed areas should be planted so that they become meadows or forested areas, rather than conventional lawn, which generally does a poor job of absorbing rainwater. Lawns also require irrigation, do not provide wildlife habitat, and are usually treated with pesticides, herbicides, and fertilizers, all of which contribute to poor water quality.
For more information, you can visit the Low Impact Development Toolkit website created by MAPC, where you can find fact sheets, the local codes checklist, a stormwater bylaw summary, and various other resources. MAPC also created three different brochures about LID: one for citizens and regulators, one for developers, and one for engineers. You can download these from the website.
These practices can be integrated into every part of site design to create a hydrologically functional lot. Trees and native vegetation provide nature’s storage of rainfall. Permeable pavement, grass swales along roads, rain gardens and amended soils store, filter and infiltrate runoff. Adding rain barrels and other cisterns provide additional water storage.