Stormwater models and learning resources:
While learning system interactions provides insight into the systems that comprise green infrastructure, the policies and plans that eventually take place embody the synergies and compromises that occur when systems, and people, interact.
The models and tools in this section present broader views of the implications and impacts of stormwater management measures. Excessive or polluted run-off can be reduced, but at what cost? That cost may be trivial in one community, catastrophic in another. Knowing which is essential to decision-making.
Green City, Clean Waters
Green City, Clean Waters: Philadelphia’s 21st Century Green Stormwater Infrastructure Program Philadelphia, Pennsylvania Hundreds of historic cities like Philadelphia experience combined sewer overflows during heavy rainstorms. Philadelphia Mayor Michael Nutter gave the green light to explore reverting from “gray,” or traditional stormwater management infrastructure, to “green” or sustainable infrastructure that mimics the natural water cycle. In 2011, Philadelphia reached an agreement with the Pennsylvania Department of Environmental Protection and the U.S. EPA to explore a largely green stormwater management infrastructure plan to reduce sewage overflows. As a result, an ambitious and comprehensive attempt to overhaul stormwater infrastructure was developed. Green City, Clean Waters (GCCW) has not only made Philadelphia the first city in the U.S. to meet both state and federal water quality mandates through green interventions, but it will also save the city an estimated $6.5 billion in construction costs over building new pipes.
Water benefits public life
Helle Soholt, CEO Gehl, advocates for social resilience as a prerequisite of water-wise cities at #embracethewater – http://www.iwa-network.org/programs/c…
Reduce Your Stormwater: Chesapeake Be RiverWise
http://www.stormwater.allianceforthebay.org/be-riverwise
The Reduce Your Stormwater website guides citizens to steps they can take to eliminate runoff and potential pollution from their property and improve their local stream and the Chesapeake Bay. The easy to use information is targeted to homeowners and includes helpful hints, technical specifications, illustrations, videos and other valuable resources.
Stormwater, rain that runs off hard surfaces and eventually into local waterways, is a major and fast growing source of pollution that affects the entire Chesapeake Bay region. Stormwater may carry sediment, nutrients from lawns, waste from farms and pets, oil and litter from streets, and other contaminants into streams or storm drains. Many local governments have recently established programs that impose fees for property owners in order to reduce stormwater.
Most homeowners can take positive steps right in their own yards. The Alliance recognizes that homeowners play a crucial role in limiting water pollution.
Penn State Integrated Hydrological Modeling System (PIHMS)
Physically-based fully-distributed hydrologic models try to simulate hydrologic state variables in space and time while using information regarding heterogeneity in climate, land use, topography and hydrogeology. However incorporating a large number of physical data layers in the hydrologic model requires intensive data development and topology definitions. Traditionally GIS has been used for data management, data analysis and visualization. In this effort we present a “tightly-coupled” GIS interface to Penn State Integrated Hydrologic Model (PIHM) called PIHMgis which is open source, platform independent and extensible. The tight coupling between GIS and the model is achieved by developing a shared data-model and hydrologic-model data structure.
Your Stormwater Dollars
This novel PSA describes the importance of stormwater handling and how your stormwater dollars are used in the budget.
US-EPA National Stormwater Calculator
https://www.epa.gov/water-research/national-stormwater-calculator
EPA’s National Stormwater Calculator (SWC) is a desktop application that estimates the annual amount of rainwater and frequency of runoff from a specific site anywhere in the United States (including Puerto Rico). Estimates are based on local soil conditions, land cover, and historic rainfall records. The Calculator accesses several national databases that provide soil, topography, rainfall, and evaporation information for the chosen site. The user supplies information about the site’s land cover and selects the types of low impact development (LID) controls they would like to use. Calculates Annual Rainfall, Runoff, Infiltration, Evaporation based on historic statistics.
The LID controls that the user can choose are the following seven green infrastructure practices:
- Disconnection
- Rain harvesting
- Rain gardens
- Green roofs
- Street planters
- Infiltration basins
- Porous pavement
Ever wondered where the rain goes?
YouTube
CIRIA’s susdrain project has launched an exciting new animation on Sustainable Drainage Systems (SuDS) that provides an engaging and digestible overview of SuDS. The short animation called “Ever wondered where the rain goes?” demonstrates how changes to the natural water cycle caused by development can be positively managed, and, how SuDS turns this challenge into an exciting opportunity contributing to better places. For more information about sustainable drainage visit www.susdrain.org or contact enquiries@susdrain.org.
National Low Impact Development (LID) Atlas
Low impact development (LID) practices, also known as green infrastructure, have been shown to be very effective in mitigating the impacts associated with stormwater runoff from development. On-the-ground examples of LID implementation, both good and bad, are needed to help local officials and others overcome the natural reticence to embrace new technologies or approaches and encourage or even require their use. The Low Impact Development (LID) Atlas was created for the National Nonpoint Education for Municipal Officials (NEMO) Network by the Connecticut NEMO Program and the California Center for Water and Land Use (http://lidmap.uconn.edu/). The LID Atlas is an interactive tool that provides examples of LID implementation throughout the country.
Surface Water: University of Nebraska-Lincoln
https://water.unl.edu/surface-water
Stormwater is water from rain and melting snow and ice. Stormwater can soak into the soil (infiltrate), be held on the surface and evaporate, or run off and end up in a nearby stream, river, or other water body. Before land is developed with buildings, roadways, and agriculture, the majority of stormwater soaks into the soil or evaporates. UN-L Nebraska Extension hosts a site providing links to a wide array of resources for stormwater management.
Seattle 2030 Districts Water and Stormwater Calculator
http://www.2030districts.org/resources/stormwater-calculator
The Seattle 2030 District, in partnership with engineering consultants Herrera, created a stormwater calculator that members can use to explore stormwater management strategies, and estimate baselines and potential savings for both stormwater management and potable water consumption.
Clean Water Howard County, Maryland
http://www.cleanwaterhoward.com/
Stormwater runoff is excess water that can’t be absorbed by pervious surfaces, or that flows off impervious areas. This runoff enters Howard County’s stormwater drainage system, where it’s carried to local waterways—and eventually the Chesapeake Bay. Along the way, stormwater runoff picks up anything in its path—including oil from cars, fertilizers, litter, pet waste, and sediment—and carries it to the streams and rivers in your backyard. These pollutants can harm plant and animal life. In addition, this runoff can cause erosion, flooding, and property damage if not properly managed. Stormwater runoff is responsible for 20 percent of the Chesapeake Bay’s pollution.
iTree suite of tools
https://www.itreetools.org/applications.php
Based on years of US Forest Service research and development, these innovative applications provide managers and advocates with tools to quantify ecosystem services and benefit values of community trees and forests at multiple scales.
iTree Design
https://www.itreetools.org/design.php
i-Tree Design allows anyone to make a simple estimation of the benefits provided by individual trees. With inputs of location, species, tree size, and condition, users will receive an understanding of tree benefits related to greenhouse gas mitigation, air quality improvements, and stormwater interception. With the additional step of drawing a building footprint – and virtually “planting” or placing a tree – tree effects on building energy use can be evaluated.
iTree Canopy
https://www.itreetools.org/canopy/index.php
i-Tree Canopy offers a quick and easy way to produce a statistically valid estimate of land cover types (e.g., tree cover) using aerial images available in Google Maps. Canopy has been expanded to include calculations of the value of the canopy in reducing air pollution and capturing atmospheric carbon. Canopy can be used by urban forest managers to estimate tree canopy cover, set canopy goals and to monitor canopy change over time. In addition, Canopy estimates can be used for data requirements in the i-Tree Hydro model and elsewhere where land cover data are needed.
iTree Landscape
https://landscape.itreetools.org/maps/
i-Tree Landscape is a web-based tool that allows users to explore tree canopy, impervious cover, land cover, and basic demographic information anywhere in the United States. Users can learn about the benefits and values that area trees provide including carbon storage, air pollution removal and hydrological effects. Landscape can also be used to prioritize tree planting and preservation efforts based on user defined objectives and the current distribution of trees, people and available space.
Climate Interactive—Milwaukee Green Infrastructure Scenario Tool
https://www.climateinteractive.org/tools/milwaukee-green-infrastructure-scenarios-tool/
Wetlands, green roofs, rain gardens and permeable pavement are among the approaches that can help communities deal cost-effectively with increased precipitation and storm water runoff. In partnership with the Milwaukee Metropolitan Sewerage District (MMSD) and with support from the Surdna Foundation we have created a prototype system dynamics simulation of investment in green infrastructure that allows for the same sort of “what-if” scenario testing that has been so effective in our other models of climate change, the transition to clean energy and resilience to drought in East Africa. The Green Infrastructure Scenarios Tool (GIST) has helped Milwaukee decision-makers and citizens test scenarios and see the solutions that best deliver storm water management, financial savings, good jobs, beautiful neighborhoods and resilience to extreme weather. https://www.climateinteractive.org
Water Environment Foundation Stormwater Institute
http://stormwater.wef.org/tag/online-tools/
The Water Environment Foundation (WEF) provides links to a comprehensive library of on-line tools. Stormwater is the only growing source of water pollution in many watersheds across the country. As urban areas grow and severe weather becomes more common, the issue of stormwater management will only escalate in importance. The growing issue of stormwater pollution coupled with regulatory pressure is driving the need for innovative approaches, training, technology solutions, and progressive financing. As such, there is a clear need for national leadership and collaboration to help forge the path to more sustainable stormwater management. The WEF Stormwater Institute focuses on addressing critical stormwater management issues as a means to protect public health and the environment. It serves as a conduit for information and feedback between the stormwater and regulatory communities. The institute is identifying cross-cutting issues, convening experts to tackle those issues, providing insights and leadership to policymakers, and helping chart a new course toward a healthier and more sustainable stormwater system in the U.S. and beyond.
Water Environment and Re-use Foundation (WERF) SELECT planning tool
http://www.werf.org/i/c/Tools/SELECT.aspx
SELECT is a simple planning level tool that enables a stormwater manager to examine the effectiveness of alternative scenarios for controlling stormwater pollution and the whole life cost associated with each scenario. Thus, the manager can make more informed decisions on which practices to permit with some confidence that they will meet imposed TMDL limits and also can have some confidence that the capital and O&M costs involved in implementing BMPs are known. SELECT uses a long-term record of hourly rainfall to drive the model; this hourly rainfall is translated into runoff using a runoff coefficient that is related to the effective imperviousness of the catchment. This runoff is introduced to the BMP. If there is capacity in the BMP, the runoff is captured; if the BMP is full, the runoff is discharged untreated to the receiving waters. The model calculates total outflow as the sum of what is treated and what is not. SELECT output data includes annual pollutant loads discharged to the receiving water, pollutant load frequency curves with uncertainty estimates, and an estimate of the whole life cost of the BMPs applied in the watershed.
RECARGA–Green Infrastructure Performance tools
http://dnr.wi.gov/topic/stormwater/standards/recarga.html
This model is used for evaluating the performance of bioretention facilities, rain gardens, and infiltration basins. Individual facilities with surface ponding, up to 3 distinct soil layers, and optional underdrains can be modeled under user-specified precipitation and evaporation conditions. The model continuously simulates the movement of water throughout the facility (ponding zone, soil layers and underdrains), records the soil moisture and volume of water in each water budget term (infiltration, recharge, overflow, underdrain flow, evapotranspiration, etc.) at each time step and summarizes the results. The results of this model can be used to size facilities to meet specific performance objectives, such as reducing runoff volume or increasing recharge, and for analyzing the potential impacts of varying the design parameters.
NOAA Climate Resilience Toolkit
http://toolkit.climate.gov/tools
Tools to help manage climate-related risks and opportunities, and to guide in building resilience to extreme events.
https://coast.noaa.gov/digitalcoast/training/gi-cost-benefit.html
To plan successfully, communities need to understand the options for addressing flood-related issues and their associated costs. This guide lays out a six-step watershed-based approach for documenting the costs of flooding, projecting increased flooding and associated costs under future land use and climate conditions, and calculating the long-term benefits and costs of a green infrastructure approach. The guide draws from four case studies (Duluth, Minnesota; Toledo, Ohio; Green Bay, Wisconsin; and He‘eia, Hawaii) to provide key considerations, recommended expertise, practical implementation tips, and lessons learned.
US-EPA Climate Resilience and Awareness Tool–CREAT
CREAT is a risk assessment application that helps utilities to adapt to extreme weather events by better understanding current and long-term weather conditions.
- Discover:Find out which extreme weather events pose significant challenges to your utility and build scenarios to identify potential impacts.
- Assess:Identify your critical assets and the actions you can take to protect them from the consequences of extreme weather events on utility operations.
- Share:Generate reports describing the costs and benefits of your risk reduction strategies for decision makers and stakeholders.
National Weather Service Local Climate Analysis Tool
https://toolkit.climate.gov/tool/local-climate-analysis-tool-lcat
The Local Climate Analysis Tool (LCAT) helps advanced users identify and predict climate-related impacts on water and weather at a local level. Originally developed to support National Weather Service field offices, LCAT offers data-driven answers to climate-related questions. The tool links local weather and water events to signals in the climate system, providing information about how climate variability and change contribute to local climate trends. This local-to-national perspective on climate can show the effect of climate variability and change on temperature and precipitation in your community in recent decades, and how those trends may continue into the future. LCAT enables users to dive all the way into data from individual weather stations or zoom out to larger regions.
US Forest Service Water Erosion Prediction Project
http://forest.moscowfsl.wsu.edu/fswepp/
The Water Erosion Prediction Project (WEPP) model is a physically-based, distributed-parameter, continuous-simulation model. Recent improvements to WEPP include enhanced computation of evapotranspiration (ET) by incorporating the Penman-Monteith method into the model, and improved calculation of subsurface lateral flow by properly setting a restrictive layer and soil anisotropic ratios. These modifications have substantially improved the performance of the WEPP model for forested watersheds. In order to further enhance the model applicability, a baseflow component needs to be incorporated to adequately represent hydrologic conditions where significant quantities of ground water flow to streams.
South Atlanta Conservation Blueprint 2.0
http://blueprint.southatlanticlcc.org/v2/index.html
Blueprint 2.0 is completely data-driven, based on ecosystem indicator models and a connectivity analysis. It prioritizes the lands and waters of the South Atlantic according to the current condition of the indicators. Better indicator condition suggests higher ecosystem integrity and higher importance for natural and cultural resources across all ecosystems collectively.
- Highest priority for shared action: the 10% of the region identified as most important for natural and cultural resources based on indicator condition.
- High priority for shared action: the next best 15% of the region. Together, highest and high priority cover the 25% of the South Atlantic geography identified as most important for natural and cultural resources based on indicator condition.
- Corridors: these connect large patches of highest priority area, optimized for efficiency and indicator condition in a least cost path analysis. This category covers 5% of the South Atlantic region.
- Medium priority for shared action: the remainder of the South Atlantic region that is in above-average indicator condition, but not already categorized as highest priority, high priority, or corridors. This category covers 20% of the geography and often captures good restoration opportunities.
US-EPA Center for Neighborhood Technologies–National Green Values Calculator
http://greenvalues.cnt.org/national/calculator.php
The National Green Values™ Calculator is a tool for quickly comparing the performance, costs, and benefits of Green Infrastructure, or Low Impact Development (LID), to conventional stormwater practices. The GVC is designed to take you step-by-step through a process of determining the average precipitation at your site, choosing a stormwater runoff volume reduction goal, defining the impervious areas of your site under a conventional development scheme, and then choosing from a range of Green Infrastructure Best Management Practices (BMPs) to find the combination that meets the necessary runoff volume reduction goal in a cost-effective way.
US-EPA Center for Exposure Assessment Modeling (CEAM)
https://www.epa.gov/exposure-assessment-models
The EPA Center for Exposure Assessment Modeling (CEAM) provides proven predictive exposure assessment techniques for aquatic, terrestrial, and multimedia pathways for organic chemicals and metals. CEAM was established in 1987 to meet the scientific and technical exposure assessment needs of the U.S. EPA as well as state environmental and resource management agencies. CEAM distributes environmental simulation models and databases for urban and rural nonpoint sources, conventional and toxic pollution of streams, lakes and estuaries, tidal hydrodynamics, geochemical equilibrium, and aquatic food chain bioaccumulation. In addition to software distribution, CEAM reviews and evaluates potential and existing software products, maintains and tests source code and command files, and provides user support. User support includes review, evaluation, and possible correction of routine run time errors or other problems encountered when using CEAM software and provides information exchange to assist users applying a model developed for one purpose to a new and different problem. Especially see Surface Water Models, https://www.epa.gov/exposure-assessment-models/surface-water-models
US-EPA Exposure Assessment Surface Water Models
https://www.epa.gov/exposure-assessment-models/hspf
The EPA Center for Exposure Assessment Modeling (CEAM) distributes simulation models and database software designed to quantify movement and concentration of contaminants in lakes, streams, estuaries, and marine environments. The surface water models were developed by the U.S. Environmental Protection Agency in conjunction with other government, academic, and commercial institutions.