Water & Human Impact: Unit 4 http://commons.wikimedia.org/wiki/File:Michael_Melgar_LiquidArt_resize_droplet.jpg

TEKS: 7.8C Model the effects of human activity on groundwater and surface water in a watershed.

Human Impact Pollution is the introduction of a contaminant into the environment. It is caused by various human actions Pollution to drinking water can cause diseases. Most ground water contamination is caused by nitrates from fertilizers used for agriculture.

Porosity vs. Permeability Porosity is a measure of the amount and size of pore space within an earth material It can vary depending upon the soil and rock. It indicates how much water a material can hold.

Particle Sizes And Porosity: High porosity Low porosity High permeability Low permeability

Porosity vs. Permeability Permeability is a measure of the ability of an earth material to let water pass through it. It is affected by porosity.  porosity =  permeability Impermeable – water is not able to pass through due to very low porosity

Brain Break!! KEEP IT CLEAN

Groundwater vs. Surface Water Groundwater is water that flows below the ground through the openings in the rocks and soil water trickles down until it reaches impermeable soil or rock.  wells and springs pull groundwater back to the surface to drink. 98% of Earth’s available freshwater is groundwater.

Groundwater vs. Surface Water Surface water includes rivers, streams, lakes, ponds, oceans, and runoff water from streets during thunderstorms. Left alone it will flow downhill until it reaches a creek or stream. The creek or stream will lead to a river that will flow into the ocean.  During that time some water will evaporate back into the atmosphere and return as rain.  80% of the water used on a daily basis comes from surface water.

Watershed vs. Aquifer A watershed is an area of land where all of the surface water within a specified area drains downward and flows to the same place.

Aquifer An aquifer is an underground area where large quantities of ground water fill the spaces between rocks and sediment to accumulate. It can cause the watertable to rise during high rains or lower when over pumped.

Are you getting it? 1. What event must occur to allow aquifers to be restored by ground water? 2. How is surface water different from runoff? 3. What is the biggest pollutant of ground water by human activity? 4. How do porosity and permeability affect the amount of potential groundwater in a region?