Unit 6B

Question 1

Groundwater Dynamics

Answer 1

• Water percolates into the ground termed infiltration
• Infiltration depends on saturation and permeability (pore spaces vs clay)
• Features include -water table, saturated zone, unsaturated zone.
• Well sucks up the water and the water table declines, if water table gets too low it will only be sucking up air

Question 2

Water table

Answer 2

• top of the saturated zone, above is the unsaturated zone
• Floods or lots of water, water table rises and unsaturated zone gets smaller
• Drought, water table decreases

Question 3

Influent stream

Answer 3

water table well below the basin, water moves into the ground

Question 4

Effluent stream

Answer 4

discharge of water out of the ground into a basin, high water table, high quality discharged water, fed by surface water and discharged water from the ground

Question 5

Lake Winnipeg Watershed

Answer 5

• Discharges up and the Nelson River to the Hudson’s Bay

- North Dakota and Minnesota water flows north

Question 6

Flooding and Flood Plains

Answer 6

• We build cities along flood plains where discharge from a river cannot be contained
• Catastrophic results when attempts to divert floodwaters fail
• Climate change expected to increase frequency and severity of flooding
• Dug deep ditches to allow the river to flow around the city instead of through the city, bridges are higher

Question 7

Heavy demand on surface and ground waters to irrigate crops (accounts for 71% of freshwater consumption in USA)

Answer 7

• Irrigation in arid & semiarid regions increase crop production
• May lead to salinization where minerals build up in soils and impair plant/crop productivity
• Expected to intensify with climate change
• Starves plants of water because water wants to stay in the salty soil
• Have to flush the soil, which causes water quality issues

Question 8

Groundwater Withdrawals – Ogallala Aquifer

Answer 8

• One of the largest aquifers in the world
• 9% reduction in size of the aquifer since 1950s when irrigation introduced
• Water table may drop 5 ft during heavy demands (2 ft per year!)

Question 9

Europe Water Shortages

Answer 9

-As river run dry right across the country, the water companies tell us we mustn’t spend more than four minutes in the shower

Question 10

Water Management

Answer 10

Goal: sustainable supply of high quality water
Challenges include population increase, linear flow, and multiple stakeholders (international, interstate/provincial)
Strategies to provide water:
-Build dams, aqueducts, and channels to alter the natural flow
-Use sea water
-Recycle water through toilet-to-tap and groundwater storage

Question 11

California Dry – Film Discussion

Answer 11

Everyone is downstream
-Shares Colorado River with other states
-Delta-network of waterways
-Built levies for freshwater to be pumped into the state
-Salt contaminants the water and it can’t be used for agriculture or freshwater
-Delta smelt-in an endangered (threatened) species
-Desalination and trenches
-Desalination-use water from the ocean, affects marine life and high source energy
-Astroturph grass
Supplies obtained through withdrawals:
-Directly from the Columbia River
-Columbia River Aqueducts
Water flow reduced:
-Species at risk
-Drought and climate change
Results in water shortages to downstream communities

Question 12

Desalination – Utilize seawater as a source of freshwater

Answer 12

Requires removal of salts
Requires filtration and pressure to remove minerals and salts
Substantial energy demands
Environmental consequences 
Habitat banking is viewed as solution

Question 13

Toilet to Tap

Answer 13

– reclaim sewage water through treatment processes (primary through tertiary) and then pump into the ground to replenish groundwater storage
-Water recycling

Question 14

What About Us?
Wise Water Use

Answer 14

Misperception that Canada is blessed with an abundance of fresh water
In reality:
-Canada has only 7% of the global supply of freshwater
-Geographically much of this freshwater resides north of the major urban developments where there is heavy demand
-Human activities have increased the level of pollution in both surface and groundwater supplies
-To increase water supply to meet demand will take huge infrastructure expansion and BIG BUCKS!

Question 15

Canada is 2nd only to the U.S. in Water Consumption

Answer 15

-Canada’s rate of water withdrawals increased by almost 90% between 1972 and 1996

Question 16

Residential Consumption

Answer 16

• The residential sector demands amount to 50% of the total supply in Canada
• Native plants, more shade, rain barrels, porous surfaces in the yard for water

Question 17

Demand Management Approach

Answer 17

Rather than seeking out new sources of freshwater and developing the system of pipes and treatment plants to deliver this, increase efficient use of our existing supply.

Question 18

The 3 R’s of Water Conservation:

Answer 18

• Reduce consumption
• But how? The 2 minute shower!
• Repair leaking pipes, faucets etc.
• This accounts for about 30% loss
• Retrofit with new efficient technologies
  e. g., dual flush toilets