Ch. 1: “Watersheds and Wetlands” Lesson 1.5: “Factors That Affect Wetlands and Watersheds” Part 2

Index of Watershed Indicators (IWI) The Index is a compilation of information on the "health" of aquatic resources in the United States. Just as a physician might take your temperature and your blood pressure, check your pulse, listen to your heart beat and respiration, evaluate your weight compared to your height, etc., the Index looks at a variety of indicators that point to whether rivers, lakes, streams, wetlands and coastal areas are "well" or "ailing" and whether activities on the surrounding lands that affect our waters are placing them at risk.

What are the Indicators? Some of the indicators are related to the condition of the aquatic resources and some are related to vulnerability -- conditions or activities that may place stress on the resources. The Environmental Protection Agency (EPA) is working to add additional indicators such as biological integrity, terrestrial condition, ground water, and air deposition to the IWI. This will help round out the picture they paint of watershed health.

The Condition Indicators = These indicators reflect the actual conditions in the watershed. 1. Fish and Wildlife Consumption Advisories - restrict consumption of locally harvested fish or game due to the presence of contaminants. 2. Contaminated Sediments - The level of potential risk to human health and the environment from sediment chemical analysis, sediment toxicity data, and fish tissue residue data. 3. Ambient Water Quality Data - Four Toxic Pollutants - Ambient water quality data showing percent exceedences of copper, chromium, nickel, and zinc. 4. Ambient Water Quality Data - Four Conventional Pollutants - Ambient water quality data showing percent exceedences of ammonia, dissolved oxygen, phosphorous, and pH. 5. Wetland Loss Index - Percentage losses of wetlands over an historic period ( ) and more recently ( ).

The Vulnerability Indicators = These indicators show whether human activities produce negative effects on the watershed. 6. Aquatic/Wetland Species at Risk - Watersheds with high occurrences of species at risk. 7. Pollutant Loads Discharged Above Permitted Discharge Limits - Toxic Pollutants - Discharges over a one year period for toxic pollutants are combined and expressed as a percentage above or below the total discharges allowed under the National Pollutant Discharge Elimination System (NPDES) permitted amount. 8. Pollutant Loads Discharged Above Permitted Discharge Limits -Conventional Pollutants - Discharges over a one year period for conventional pollutants are combined and expressed as a percentage above or below the total discharges allowed under the National Pollutant Discharge Elimination System (NPDES) permitted amount. 9. Urban Runoff Potential - The potential for urban runoff impacts is estimated based on the percentage of impervious surface in the watershed (roads, paved parking, roofs, etc.)

The Vulnerability Indicators = These indicators show whether human activities produce negative effects on the watershed. 10. Index of Agricultural Runoff Potential - A composite index comprised of a) a nitrogen runoff potential index, b) modeled sediment delivery to rivers and streams, and c) a pesticide runoff potential index. 11. Population Change - Population growth rate as a surrogate of many stress-producing activities from urbanization. 12. Hydrologic Modification - Dams - This index shows relative reservoir impoundment volume in the watershed. The process of impounding streams changes their characteristics and the reservoirs and lakes formed in the process can be more susceptible to pollution stress. 13. Estuarine Pollution Susceptibility Index - This measures an estuary's susceptibility to pollution based on its physical characteristics and the propensity to concentrate pollutants. (The preceding information has been provided by the EPA.)

Health of US Watersheds Describe the overall quality of PA’s watersheds: Figure 1.24: PA’s watersheds are generally healthy, boasting better water quality and less vulnerability. Describe the overall quality of the nation’s watersheds: About 23% of the nation’s watersheds have more serious water quality problems today than they once did. About 15% of all US watersheds have better water quality today than they did in the past. About 1 in 3 watersheds in the US has some kind of water quality problems.

PA’s Stream ReLeaf Program Explain the objectives of PA’s Stream ReLeaf program: 1. Restoration of streamside buffers. 2. Conserving streamside buffers. 3. Public education on the importance of streamside buffers. 4. Public relations activities should raise awareness about streamside buffers. 5. Data on streamside buffers should be collected, evaluated, and reported.

Watershed Education Program Explain the objectives of the Watershed Education (WE) program: 1. Developing an appreciation for the local watershed and understanding the effects of human activities on the drainage basin. 2. Spark interest in aquatic ecosystems. 3. Share the results of studies with other schools, organizations, and agencies that are working to protect the watershed.

Effects of Natural Events Briefly describe how each of the following natural events can affect watersheds: 1. Floods: 2. Erosion and deposition: 3. Drought: 4. Volcanic eruptions: 5. Fires: 6. Wind: 7. Global climate change: