1. Surface Water

2. Where Does the Water Go? Precipitation ____________ _____________
Percolates into
Soil/rock
Runoff
____________
_____________
Lakes, ponds, streams
Ocean, wetlands

3. 52% 8%
Surface
Water
38% 1% 1%

4. ________: Tiny water channels
River Systems
__________
Collects
________: Tiny water channels
Merge
________________
Merge
_________
Empty
_________

5. River System
_________________: Network of rivers and streams draining a river basin
_____________: Feeder streams
Major River Systems
_______________
________________
_________________

7. Pennsylvania’s Major Rivers
Susquehanna (Main)
Susquehanna (West)
Delaware
Schuylkill
Juniata
Lehigh
Ohio
Allegheny
Monongahela
Lackawaxen
Lackawanna
Youghiogheny
Shenango
Clarion

8. Major Drainage Patterns
Drainage patterns depend on:
___________________: Physical characteristics of the land.
Rocks over which the water travels

9. Types of Drainage Patterns
______________: Resembles a mature tree
Most river systems in PA
Main river forms trunk
Uniform bedrock
Function of the slope of the land

10. Types of Drainage Patterns
____________: “Spokes on a wheel”
Streams flow from a high central area
__________

11. Types of Drainage Patterns
______________:
Rock broken by a series of faults and fractures
“Bends” in stream form right angles

12. Types of Drainage Patterns
_____________:
Type of rectangular
Tributary streams are parallel to each other
Rock alternate between hard and soft

13. Types of Drainage Patterns
______________:
Large body of water (lake) at the center
“Feeder Streams” empty into the lake

14. Drainage Pattern Summary

15. Watersheds (Drainage Basin)
Watersheds: The area of land that is drained by a river.
Surrounded by topographic highs called Divides.
Divide: Any ridge between two streams along which precipitation runs off.
PA has 104 watersheds

16. Watersheds (Drainage Basin)
6 Major PA Watersheds
_________________ Basin
______________ River Basin
___________________ Basin
____________________ Basin
_____________________ Basin

17. PA Watersheds

18. Drainage Pattern Summary

19. Identifying the Boundaries of a Watershed (Delineation)
Step #1: Identify the stream to be delineated.
Step #2: Using a pencil and ruler, draw a series of lines (1-2 cm in length) perpendicular to the stream, spaced 1 cm apart.
Step #3: At the headwaters, draw several lines radiating outward.
Step #4: Follow the perpendicular lines drawn and find the highest elevation that is closest to the steam.

20. Identifying the Boundaries of a Watershed (Delineation)
Step #5: Place an “X” at the highest elevation point.
Step #6: Repeat steps #4 & #5 for all of the perpendicular lines drawn.
Step #7: Connect the “X’s” to outline the boundary of the watershed.