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Nonpoint Source Water Pollution

Nonpoint Source > Watershed Assessment > Water Monitoring and You > Collecting Data Collecting Data

There are several approaches for gathering data about your watershed. Windshield surveys allow you to witness sources of pollutants in the watershed first-hand, while desktop surveys might uncover other documents that assess cultural trends in the watershed. A canoe float down navigable waterways might help you to see problems from “the stream’s eye view” and gathering and analyzing water samples directly measures the health of the stream. No matter which approach you use, an inventory is a great opportunity to engage stakeholders in caring for their watershed.

Desktop Survey

A desktop survey compiles already-available information about your watershed to lessen the amount of data you need to collect yourself. Many online resources exist to provide information about watersheds. Some of these are stored as reports while others contain digital information stored as a Geographic Information System, or GIS.

  • Interactive Maps and Geospatial Downloading (Indiana Geological Survey):
    • The Indiana Geological Survey offers a suite of interactive mapping websites which allow users to create custom maps using a variety of geographic, geologic, environmental and demographic content. The maps can be viewed or printed at any scale using only a web browser. Desktop GIS users may also connect to the map services directly and download the data for use with existing GIS applications.
  • Google Maps and Google Earth:
    • Google Maps and Google Earth can give you the “bird’s eye-view” of your watershed. From this vantage point, you can get a general picture of land use, potentially see sediment plumes, identify riparian buffers, and even see some structural practices. You can also use Google Maps to record and share information in a free, online format.
  • Purdue University Local Decision Maker:
    • This online mapping tool provides maps and information related to comprehensive planning in Indiana. A clickable map is available as a resource to retrieve local planning information for each county that has a comprehensive plan.
  • Indiana’s 303(d) Impaired Waters List and Total Maximum Daily Load reports:
    • Indiana’s 303(d) Impaired Waters List contains a listing of waterbody segments that have been determined by the state as impaired. States are required to prepare Total Maximum Daily Load (TMDL) reports for all waterbodies on the 303(d) Impaired Waters List. These reports include data for the pollutant of concern and can provide the basis for a watershed management plan.
  • Indiana Water Monitoring Inventory:
    • The Water Monitoring Inventory is a Google based map of water monitoring stations across the state. It includes site name, parameters sampled, and dates sampling has occurred or is occurring, as well as how to obtain the data collected. Inclusion on this site is voluntary, so although it is the most comprehensive clearinghouse of data, it may not include everything. You may also upload your data to this site.
  • Indiana Water Quality Atlas (IWQA):
    • This website includes information about the downloadable application as well as the state and federal reference and water quality data layers in an interactive mapping feature. IDEM water quality data and sample site locations can be downloaded in spreadsheet format. GIS datasets are not downloadable from this site, however local and other external sources of data are usable in the application along with the provided datasets. Additionally, there are several templates for watershed management plan maps for coordinators to start their inventory and other mapping needs.
  • USGS Stream Gage Data (Flow):
    • Flow and stage data for streams that contain a USGS gage are available from this site. Bookmark this website to assist in calculating loads if you have not collected flow data during your sampling effort. This site even includes a tutorial to help you retrieve data and interpret the results.
  • Geographic Information System (GIS) Tools for Watershed Management:
    • This website contains links to several web-based GIS tools, including an online watershed delineation tool that calculates the watershed area draining to a point selected on an interactive map. Once you have delineated the watershed, you can use other tools on the website to estimate the impervious area, run hydrologic models such as L-THIA, or download the data for use in a GIS program.
  • U.S. EPA's EnviroFacts Data Warehouse:
    • EnviroFacts is a database that is connected to state databases in many program areas, including permitted dischargers, drinking water facilities, brownfields, hazardous waste sites, grants awarded in area of interest and compliance history. Although there is a note on the site that information from Indiana has been frozen,, everything from Indiana should be available in the database, barring any occasional glitches.

Windshield Survey

A “windshield survey” is exactly what it sounds like – a survey of the watershed from behind the windshield of your car. This type of data collection is useful for verifying digital information and for pinpointing problem areas. While you are driving (or canoeing) the watershed, look pollution effects, such as green or muddy water, and potential pollutant sources, including possible failed septic systems and livestock with direct stream access. It might be useful to bring along a map and an extra person so that one person can drive while the other takes notes.

The following resources may be helpful to you as you prepare for your windshield survey:

Gathering Water Quality (Monitoring) Data

For gauging the current health of your stream, there’s nothing like water quality monitoring. Looking at the physical, chemical, and biological parameters of your stream can tell you both real-time and long-term conditions. It’s also a good way to get stakeholders involved.

  • National Environmental Methods Index:
    • Interested in the different ways you can measure nitrogen? Not sure how you are going to collect biological information? Use this United States Geological Survey-maintained website to decode those elusive methods numbers and find out how the pros measure water quality parameters. There’s even an estimate of cost associated with each method.
  • USGS Water Resources:
    • Use this website to find USGS data and publications on your watershed, general surface water quality information, stream gage information, daily streamflow conditions, and Indiana-specific information. This is a large site – take a look around and find out what is useful for you.
  • NRCS Handbooks:
    • Handbooks related to animal waste management, hydrology, nutrient management, nutrient credit trading, pest management, stream restoration, water management, and water quality assessment are available at this site. Though the water quality assessment handbook [pdf] is probably most pertinent for this stage of planning, there is quite a bit of information available.
  • Purdue Catalog of Monitoring Protocols Used by Indiana Agencies:
    • This wiki has compiled monitoring protocols information for all of Indiana’s State and Federal agencies into one convenient site. No access code is required to access the site, but the wiki cannot be edited without permission from Purdue University.
  • IDEM External Data Structure:
    • The External Data Framework is a document provided by IDEM for groups who wish to submit data to IDEM for consideration during the 305(b)/303(d) assessment and listing process.
  • Indiana Water Quality Standards, Suggested Water Quality Targets [PDF] and U.S. EPA Water Quality Criteria Home Page:
    • Indiana’s Water Quality Standards are outlined in Title 327 Indiana Administrative Code Article 2 (327 IAC 2). These rules govern water quality standards for surface waters in the non-Great Lakes basins of Indiana (Rule 1-6), Great Lakes basins (Rule 1.5), limited use and outstanding resource waters, and ground water (Rule 11). IDEM has developed a listing of potential targets and references for watershed management plans. To view these targets, visit the “Suggested Targets” page. U.S. EPA has also developed suggested national targets to protect designated uses on their Water Quality Criteria home page.
  • Chapter 2 Hoosier Riverwatch Training Manual [PDF]:
    • Designing a water quality study is not a cookie-cutter affair. Chapter 2 of this manual walks you through the questions you should answer in order to design an appropriate monitoring program.
  • Hoosier Riverwatch Volunteer Monitoring Training:
    • Hoosier Riverwatch training takes you through the basic theory and practice of taking stream samples and habitat measurements so that you can go back to your watershed and sample streams. During the training, you will practice using the test kits and interpreting your results.
  • Watershed Assessment of River Stability & Sediment Supply (WARSSS) procedure:
    • Sediment is the number one threat to Indiana’s stream health. Use this assessment to determine where your sediment load is coming from, the stability of the stream’s banks, and to develop appropriate restoration measures.
  • U.S. EPA Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers:
    • This handbook provides a method to measure habitat, periphyton (algae), benthic macroinvertebrates, and fish. Appendices include sample field and laboratory data sheets, instructions for completing the data sheets, and examples of high quality and low quality streams for each parameter. While data collection is relatively easy using these protocols, analysis requires a higher level of sophistication.