watershed reading. 1. watershed = area of land that drains precipitation to a body of water 2....
TRANSCRIPT
Watershed Reading
1. Watershed= area of land that drains precipitation to a body of water
2. Depends on topography- Divided by ridges (hills) drainage divides
Video Video 2
3. Drainage Divide One watershed on one side of hill
Other watershed on other side of hill
Ridges determine where water will flow
4. Drainage Patterns
DendriticLooks like a tree
Most common pattern in PA
Drainage Patterns
Radial Flows from a high point (volcano, mountain)
Circular
Drainage Patterns
RectangularForms right angles
Drainage Patterns
Trellis ** What we have Valleys in areas
of soft rocks; ridges (hills) in areas of hard rock
Drainage Pattern Questions
5. Near volcanos & mountains radial
6. Most common dendritic
7. Alternating hard & soft rock trellis
8. Continental Divide Many continents have a
continental divide (imaginary lines that follow ridges). The continental divide in North America separates into 2 major watersheds West side drains into the Pacific
Ocean East side drains into the Atlantic
Ocean
10-12. PA WatershedsMethacton HS is in the Delaware watershed
Susquehanna is the largest PA watershed.
Into what river will all smaller rivers in this area flow?
If we follow the Delaware River out, what body of water will we come to?
Do our actions around the Schuylkill River affect the Delaware Bay?
13. Importance of Watersheds
Habitats to many organisms Collect and store rainfall Water for agriculture, industry and
households Recharges groundwater Wetlands within the watersheds help to
filter out pollutants and absorb water to prevent flooding
• We are connected to others downstream
• Our waterway flows into other waterways.
• Our watershed drains into other watersheds.
• Our mess / our pollution travels downstream.
Watershed Impacts Downstream
Watershed Pollution Nonpoint Source Pollution Cannot be traced to one specific source- generally comes from all of us.
Stormwater Runoff
When rain or melting snow washes over the ground, pollutants such as leaked oil from cars, dog waste and litter gets carried into our waterways.
It is often nonpoint source pollution, so it’s a little bit here and a little bit there, which adds up!
Agriculture
Pesticides/fertilizers – pollute groundwater & causes eutrophicationAnimal Waste- causes disease/pollutes drinking waterOvergrazing- causes erosion more sediment in water clogs fish gills
Urbanizat-ion
Storm water runoff washes all of the following into bodies of water: Pet waste cleaning chemicals Oil Gas Detergents Paints
Mines Heavy metals in runoff acidify the bodies of water
Industry Smog causes acid rain (chemicals released into air)Industrial waste dumped into waterways.
Waste Disposal
Sewage- untreated human waste causes disease & death in drinking waterLandfills- chemicals/pollutants from garbage sink into soil/groundwater when it rains
Solutions