1. Ground water

2. Rainfall is absorbed (infiltrates) farmland soil

3. Because of urbanization, the rainfall cannot infiltrate, so it’s runoff,

4. Where does the water go???

5. Frequent large storms can exceed the system's ability to handle the load. This can cause mixing of sanitary and storm sewer water that results in flooding an water back-up

7. If the sewer system is full or it can’t handle the rate of water flow, the rainwater has no where to go but back (up) into your household drains.

8. The Deep Tunnel Project

9. Begun in 1975, and at one time the nation's largest municipal water pollution control project
It involves the construction of 109 miles (174 kilometers) of tunnels 9 to 33 feet (3 to 10 meters) in diameter.
Excavated in limestone bedrock as much as 350 feet (107 meters) below the surface.

10. These tunnels will collect any combined sanitary and storm sewer flows and send them to reservoirs for storage…

13. …until the area's water reclamation plants can treat and safely discharge the water.
The Deep Tunnel is designed to reduce and nearly eliminate the release of untreated water to streams, Lake Michigan, and people's basements.

15. Groundwater

16. Groundwater is the most abundant available source of fresh water
Rivers, lakes, streams = 1.4% of fresh water

18. Pore spaces are filled mainly with air
Zone of aeration
Unsaturated zone
Pore spaces are filled mainly with air
Zone of saturation
All pore spaces in the material are filled with water
Water within the pores is groundwater
Water table –
the top of the zone of saturation

19. Groundwater
Precipitation (rain water) that enter (infiltrates) the ground.
And is STORED in the ground in the spaces between rock particles
in aquifers.
(Groundwater is the most abundant available source of fresh water)
Factors that affect the amount of water that infiltrates the ground:
type of rock or soil
climate
topography
vegetation
land use
soaks-in

20. Soil and vegetation allow water to slowly infiltrate
Urban streets, concrete, asphalt roads and buildings do not allow water to infiltrate and the water quickly
runs-off

21. What determines if precipitation will INFILTRATE or RUN-OFF?
Figure 5.3
What determines if precipitation will INFILTRATE or RUN-OFF?

22. Porosity amount of pore spaces, voids, openings.
Ground materials ability to HOLD water.
Determines storage of groundwater.
The percent % of the total volume of material that consists of pore spaces

23. What percent of the rock is pores spaces??

24. Porosity factors: 3-S’s
Size of particles: (large, small, fine)
Shape of particles (rounded or angular)
Sorting of particles:
- well-sorted: all the SAME size and shape
- unsorted: mixed, DIFFERENT size and shape
Compactness of particles
Which is well-sorted? Compacted? Un-sorted?

25. Porosity Lab: Compare the porosity of materials
Material
Total Volume of
Material (dry)
cm3
Volume of water
In spaces
% of spaces
in total volume
Rank #1 - #4
(1 is highest porosity)
Marbles
Glass BB’s
Pebbles
Aquarium
gravel
Fine sand

26. Post-lab questions:
1.Which material that had highest porosity: ___________________
Which material that had lowest porosity: ___________________
2.Which of your materials was a well-sorted material: _______________
Which of your materials was an unsorted material: ________________

27. Post-lab graphs
1. Sketch a graph that shows the relationship between porosity and particle size
porosity
Particle size
2. Sketch a graph showing the relationship between porosity and sorted
Unsorted well-sorted
3. Sketch a graph showing the relationship between porosity and shape.
(round vs. angular)

30. sa
Rank the following as #1 for the highest porosity and #5 as the lowest porosity.
And describe factors
sand
Clay soil
Good porosity
Due to:
Round shape
Same size
well-sorted
High porosity
Due to:
Same big size
Same shape
Well-sorted
High porosity
Due to:
Big size
But.. unsorted and angular
Good porosity.
Due to:
Same size
Well-sorted
LOW porosity
Due to:
unsorted
Small clay particles fill-in the pore spaces between the large particles.

31. What is the POROSITY of the rock? __________%
20 ml of water filled the spaces
What is the POROSITY of the rock? __________%
50 cm3 of dry rock