Where does Freshwater come from? 10.3 Sources of Freshwater Where does Freshwater come from? 10.3

Run-off Only 1% of earth’s fresh water is easily accessible! Most freshwater is TRAPPED in ice! After heavy rain showers, mini-rivers of fresh water wash over sidewalks and roads….. ->All this water is flowing across the city to run into lakes & ponds ( this flow is called Run-off)!

Factors that Affect run-off Run-off is higher in some areas than in others. Ground material (is the ground covered in rock or dirt), the amount of rain, length of time it rains, slope of the land, amount of vegetation on ground amount of development in area (buildings in the way)

Drainage Basin When rain falls and runs-off…. it works its way into a common river drainage basin or watershed-

Ground Water An Aquifer is a porous layer When water makes its way into small spaces (the pores) of rocks, its called ground water Water always wants to flow from a high elevation to low elevation An Aquifer is a porous layer in the ground that allows water to pass through

Glaciers Almost 2/3 of the world’s fresh water is trapped in large masses of snow and ice called GLACIERS. Glaciers slowly flow downhill and in the summer they melt, adding massive amounts of run-off to our lakes – think about our Okanagan lake in the summer how it has a higher level of water

Receding Glaciers

Alpine and Continental Glaciers

Crevasse = deep cracks