1. Freshwater

2. The Water Cycle

3. Topographic Maps Topography The surface features of the Earth
Determines where water will collect in streams, rivers, ponds, and lakes

4. Topographic Maps A type of map which shows a region’s topography
Show both natural features, such as rivers and hills, and constructed features, such as roads and buildings

6. Topographic Maps
Contour Lines connect points on a map that have the same elevation compared to sea level
Contour Intervals refer to the change in elevation between one contour line and the next one

9. Topographic Maps
The spacing and direction of the contour lines will help you determine the shape of the land
The closer the lines, the steeper the slope
A V-shape usually indicates a stream or river, with the V pointing upstream
Contour lines with hash marks indicate a depression

12. Freshwater
If more precipitation falls than is absorbed by plants or the ground, runoff occurs.
The water collects in the lowest regions in either streams, rivers, ponds, or lakes.

13. So what exactly is the difference between a pond and a lake?
Freshwater
So what exactly is the difference between a pond and a lake?

14. Freshwater
A pond is just a small lake in which enough sunlight reaches the bottom to support plant growth

15. River Systems
A river system is made up of a main stream and all the feeder streams, called tributaries.
Watershed, or drainage basin, is the land where all runoff enters the same river system.

16. River Systems
Watersheds are separated by ridges or elevated regions of high ground called divides

17. River Systems
As runoff moves across the land, it erodes the surface into a narrow ditch called a gully
Continued precipitation, erosion, and widening of the gully leads to a permanent stream

18. River Systems Channel- the path that a stream follows
The stream carries more than just water as it flows- soil, loose rock, dissolved minerals
All of the materials carried by a steam are the stream load

19. River Systems
Suspended Load- fine sand and silt that does not sink to the stream bed
Bed Load- coarse sand, gravel, and pebbles that grind at the stream bed as they are carried downstream
Dissolved Load- minerals that are dissolved in the water

20. River Systems
Erosion is also affected by a streams discharge and velocity
Discharge- the volume of water carried by a stream in a given amount of time
Velocity- the speed the water flows

21. River Systems Velocity is affected by the topography
Gradient describes the steepness of the land’s slope
Near the headwaters, the gradient is steep
Near the mouth, the gradient is gentle

22. River Systems Stages of a River Youthful River
Erodes stream bed more than the banks
Steep V-shaped valleys
Waterfalls and rapids are common
Few tributaries

24. River Systems Mature River Many tributaries Erosion occurs along banks
Wide, relatively flat valley
Meanders- curves formed as erosion takes place
Oxbow lakes can be formed as a meander straightens out

26. River Systems Old Rivers Low gradient Flows slower than a mature river
Few, but rather large, tributaries
Less erosion

28. River Systems Rejuvenated River
An old or mature river whose gradient has become steeper due to movement of the Earth’s crust
Step-like terraces are seen as the valley floor is uplifted and the river cuts through creating a new valley floor

30. Groundwater
Precipitation that does not run off directly into streams will seep into the soil filling any air spaces between particles of rock and sediment.
This water found beneath the Earth’s surface is called groundwater.

31. Groundwater A body of rock which stores water is called an aquifer.
Regions with sediments such as sand and gravel, sedimentary rock, or fractured rock can all be areas with large aquifers.

32. Groundwater
There are two main variables that help decide how much water can be stored by a particular type of rock.
Porosity
Permeability

33. Groundwater Porosity The percent of open spaces in the rock
Sorting- well sorted particles of rock will be similar in size and results in high porosity. Poorly sorted rock will have low porosity
Packing- Loosely packed particles will have plenty of pore space, tightly packed particles will have little or no pore space

34. Groundwater Permeability
Permeability indicates how freely water passes through the open spaces in it
Rock made of large, poorly sorted particles is the most permeable
Large cracks will increase permeability
Rocks that prevent the flow of water are said to be impermeable

36. Groundwater Zone of Saturation Water Table
Layer of the ground where all of the pores are filled with water
Water Table
The upper surface of the zone of saturation. This level may rise or fall.

37. Groundwater Zone of Aeration
Layer of ground between the water table and the earth’s surface.
Upper portion near surface will be moist
Lower portion near water table will be moist
Middle region will normally be dry

40. Groundwater
As water is removed from an aquifer, new water must take its place in order to recharge the aquifer
This can be done either by rainfall or the movement of groundwater based on topography

42. Groundwater Ordinary Wells and Springs
A well is a hole dug below the water table that fills with groundwater.
A spring is a natural flow of groundwater to the earth’s surface that is found where a low spot in the ground is beneath the water table.

43. Groundwater
Groundwater can be pumped out of a well faster than it flows through the ground. This lowering of the water table near the well is called a cone of depression.

45. Groundwater Artesian Wells and Springs
Wells and /or springs whose aquifer is located beneath a layer of impermeable rock called a cap rock.
Water is pushed to the surface by pressure so no pumping is required.

47. Groundwater
If groundwater is located in a region where magma is close to the surface, hot springs can be formed.
A hot spring must have water as warm as human body temperature (37˚C)

49. Groundwater
Hot springs can mix with the soil to form mud pots, areas of hot, thick, bubbling clay.
Hot springs that erupt above the surface are called geysers

51. Groundwater
As groundwater passes through permeable rock it dissolves some of the minerals that make up the rock.
Calcium, Magnesium, and Iron

52. Groundwater Hard water has large amounts of dissolved minerals
Soft water has relatively few dissolved minerals
Hard water can affect soap suds, taste, and leave deposits.

53. Groundwater Hardness

54. Groundwater
In certain sedimentary rocks such as limestone, groundwater erosion can create caverns.
As this water evaporates, the dissolved calcite solidifies forming stalactites and stalagmites

56. Groundwater
Caverns close to the surface may be prone to having the roof collapse forming a sinkhole
Sometimes a series of sinkholes occur that leave part of the roof of the cavern intact, this forms a natural bridge