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  1. Home
  2. National Pollutant Discharge Elimination System (NPDES)

Data and Mapping Tools for NPDES Permittees Planning for Resiliency

  • Tools to Enhance Resiliency
  • Data and Mapping Tools
  • Case Studies

National Oceanic and Atmospheric Administration (NOAA) Atlas

NOAA Atlas provides precipitation frequency estimates and associated information. NOAA Atlas 15, currently being updated, will be the first iteration that will (1) develop precipitation frequency estimates for the entire United States and its territories, and (2) update the NOAA Atlas 14 precipitation frequency standard while accounting for changing climate conditions.

Creating Resilient Water Utilities (CRWU)

EPA's Creating Resilient Water Utilities (CRWU) initiative provides drinking water, wastewater, and stormwater (water sector) utilities with practical tools, training, and technical assistance to increase system resilience. Tools include:

  • Risk Assessment Tools
    • Resilient Strategies
    • Climate Resilience Evaluation and Awareness Tool (CREAT) provides a list of utility assets, possible threats to assets, and measure utilities can implement to potentially reduce impacts.
  • Climate and Weather Data Maps
  • Trainings
  • Technical Assistance
  • Case Studies and Stories from the Sector
  • Resources for Funding Climate Adaption

FEMA's Flood Mapping Tools

Various flood mapping tools use observed data to help communities better understand their level and type of flood risk through geographic information system (GIS) data layers. Examples include the National Flood Hazard Layer and the National Risk Index. To assist federal agencies, non-federal partners, and grantees of federal funding, FEMA launched the Federal Flood Standard (FFRMS) Support Tool to assess if projects are located in a floodplain and their vulnerability to future flooding scenarios.

Locating and Selecting Scenarios Online (LASSO)

Developed by EPA, Locating and Selecting Scenarios Online (LASSO) helps users select which climate projections are applicable using multiple variables (e.g. annual precipitation, temperature).

National Water Information System

National Water Information System is a publicly available portal in which users can access data on current and historical stream levels, stream flow, reservoir and lake levels, surface water quality, and rainfall from USGS.

Sea Level Rise Viewer

Sea Level Rise Viewer is a mapping tool developed by NOAA that visualizes sea level rise and coastal flooding scenarios.

Climate Mapping for Resilience & Adaptation (CMRA)

Climate Mapping for Resilience & Adaptation provides an Assessment Tool that shows climate-related hazards (i.e., extreme heat, drought, wildfires, flooding, and coastal inundation) based on modeled history and projected time periods. CMRA was developed by the United States Global Change Research Program (USGCRP) and is managed by NOAA’s Climate Program Office. For more information about these data, visit the CMRA Assessment Tool Data Sources. For more information on how to use CMRA, visit the CMRA User Guide.

U.S. Climate Resilience Toolkit

U.S. Climate Resilience Toolkit provides tools, data, training courses, case studies, a framework to help build resilience in communities and businesses, and more. The Climate Explorer Tool provides interactive graphs and maps of past and projected climate data by county in the U.S. The toolkit was developed by the Global Change Research Program and is managed by NOAA’s Climate Program Office. For more information about these data used, visit the About the U.S. Climate Resilience Toolkit Climate Explorer.

Hydrologic and Water Quality System (HAWQS)

Hydrologic and Water Quality System (HAWQS) is a web-based, interactive water quantity and quality modeling system to simulate the effect of management practices on water quality. HAWQS substantially enhances the usability of Soil and Water Assessment Tool (SWAT), its core modeling engine, to an extensive array of crops, soils, natural vegetation types, land uses, and scenarios for hydrology and the water quality parameters such as sediment, pathogens, nutrients, biological oxygen demand, dissolved oxygen, pesticides, and water temperature. HAWQS has interactive web interfaces and maps; pre-loaded input data; outputs that include tables, charts, and raw output data; a user guide, and online development, execution, and storage of a user's modeling projects.

National Stormwater Calculator

National Stormwater Calculator estimates the annual amount of stormwater runoff from a specific location anywhere in the United States. Estimates are based on local soil conditions, land cover, and historic rainfall records. The calculator includes changes in seasonal precipitation levels, the effects of more frequent high-intensity storms, and changes in evaporation rates based on validated Intergovernmental Panel (IPCC) scenarios. Users can enter any U.S. location and select different scenarios to learn how specific management and design approaches can prevent pollution.

Storm Water Management Model (SWMM)

Storm Water Management Model (SWMM) is used for planning, analysis and design related to stormwater runoff, combined and sanitary sewers, and other drainage systems in urban areas. There are many applications for drainage systems in non-urban areas as well. The Storm Water Management Model Climate Adjustment Tool (SWMM-CAT) is an add-in tool to SWMM. It is a simple to use software utility that allows future projections to be incorporated into the Storm Water Management Model. SWMM accepts monthly adjustment factors for time series that could represent the potential impact of future conditions and provides a set of location-specific adjustments.

Climate Change Indicators: Streamflow

Climate Change Indicators: Streamflow describes trends in the amount of water carried by streams across the United States, as well as the timing of runoff associated with snowmelt. These maps show percentage changes in the minimum annual streamflow for rivers and streams across the country based on the long-term rate of change. Minimum streamflow is based on the consecutive seven-day period with the lowest average flow during a given year.

National Pollutant Discharge Elimination System (NPDES)

  • About NPDES
    • Permit Basics
    • State Program Information
    • Permit Limits
    • Program Management and Oversight
    • NPDES Regulations
    • Other Federal Laws that Apply to the NPDES Permit Program
  • All NPDES Program Areas
    • Animal Feeding Operations
    • Aquaculture
    • Forest Roads
    • Industrial Wastewater
    • Municipal Wastewater
      • Combined Sewer Overflows (CSOs)
      • Sanitary Sewer Overflows (SSOs)
      • Peak Flows
      • Integrated Planning
    • National Pretreatment Program
      • Standards and Requirements
      • Roles and Responsibilities
      • Events, Training and Webinars, and Publications
    • Pesticide Permitting
    • Stormwater
      • Construction Activities
      • Industrial Activities
      • Municipal Sources
      • Transportation Sources
      • Oil and Gas Permitting
      • Stormwater Planning
      • EPA's Residual Designation Authority
      • Rules and Notices
    • Water Quality Trading
  • NPDES Technical Resources
    • Resources for Permit Writers
    • NPDES Permit Writers' Manual
    • NPDES Training
    • Tools
    • Electronic Notice of Intent (eNOI)
    • NPDES Applications and Forms
Contact Us About NPDES
Contact Us About NPDES to ask a question, provide feedback, or report a problem.
Last updated on December 18, 2024
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