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Why Care for Your Watershed?. Charleston, OR. The Oregon Coast Education Program. Watersheds provide water – and the resources that water provides. What Is A Watershed?. ... the area of land that drains to a particular point along a stream. (Lane Council of Governments).
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Why Care for Your Watershed? Charleston, OR The Oregon Coast Education Program
Watersheds provide water – and the resources that water provides.
What Is A Watershed? ... the area of land that drains to a particular point along a stream. (Lane Council of Governments) … a ridge of high land dividing two areas that are drained by different river systems. (Free Online Dictionary) … the land that surrounds and drains rain, snowmelt, and other water into a lake, pond, wetland, stream, or river. (Minnesota River Basin Data Center)
Most watersheds combine urban, rural, natural & cultural elements
Parts of a Watershed Sub-basin or tributary watershed Some typical features of watersheds
Precipitation, surface flow, ground water flow, evaporation, and transpiration of water by plants recycle water through the atmosphere, soils, streams, and bedrock formations.
Common Ways People Change Watersheds • Alter land cover and use (e.g., agriculture, urban development) • Simplify surface pathways (e.g., drainage ditches, canals, storm sewers) • Add things to water (e.g., fertilizers, sewage) • Increase runoff and sedimentation from parking lots, roofs, roads • Increase risk of flooding
The Stream Margin:A Vital Transition Zone Riparian Area: The area adjacent to a lake or stream, consisting of the area of transition from an aquatic ecosystem to a terrestrial ecosystem. Riparian Area Functions Water Quality Flood control Aquatic habitat Wildlife Habitat Aesthetic value
Estuaries & Watersheds Estuaries are the places where The ebb and flow of the tides connect a watershed to the ocean.
Surface Water: The Visible Watershed • In the United States, 60% of all public water supplies (including Bandon’s) use surface water… • In Oregon, surface water is really important. Public water suppliers use 5 times more surface water than ground water • In Oregon Surface water is especially important because salmon are also important to us. • Virtually all municipal waste water is discharged into surface water….. (Think about that for a moment!)
Ground Water: The Watershed We Don’t See • Important water supply for Oregonians. 40 percent of public water supplies use wells. • More than 600,000 Oregonians provide their own drinking water and 70% of this water comes from private wells. • Many Oregon rivers and streams depend on ground water, especially in summer, when ground water influences stream flow, water chemistry and water temperatures. • In some streams ground water is essential to the survival of salmon and other fish that depend on cold water.
Ground Water: The Watershed We Don’t See • Over the last 20 years, ground water studies and monitoring of public water supplies revealed impairment or reason for concern in 35 of 45 ground water study areas in Oregon. • Nitrate is the most common contaminant in ground water. • 16% of 2,187 wells sampled exceed the EPA drinking water standard for nitrate, a form of Nitrogen.
Nitrogen, Nitrates & Nitrites • Nitrogen, a common element, is necessary for life. It is used to build proteins. • Earth’s atmosphere is 70% nitrogen. • Before living organisms can use it, nitrogen gas must be chemically “fixed” to make ammonia, nitrates and amino acids. • Nitrogen-fixers: • alder trees • blue-green algae • beans and leguminous plants • soil bacteria • lightning and cosmic rays!
Nitrification: • When plants and animals die, their proteins are broken down by bacteria to form ammonia. • Other bacteria convert the ammonia to nitrite. • Still other bacteria convert the nitrite to nitrate, which fertilizes new plant growth. • Denitrification: • Bacteria and fungi break down nitrates to obtain oxygen and return nitrogen gas to the atmosphere.
Other Sources of Nitrates In Ground Water & Surface Water.. • Chemical Fertilizers including • agricultural fertilizers; • turf grass fertilizers; • Septic tank effluent or leaking sewer lines; • Animal waste Including: • Pets • Domestic animals • Wild animals • Can you see the human connections? • It is really difficult to remove Nitrates from water
Too much nitrogen? Adding too much nitrate (and phosphate) to the water is called eutrophication: a cause of algae and plankton blooms. Algae blooms use up the oxygen on the water leading to fish kills, dead zones, and the production of more nitrates.