the coming water wars. purpose provide a better understanding of the connection between water...
TRANSCRIPT
Purpose
• Provide a better understanding of the connection between water resources and conflict
• Provide an overview of water operations form source to tap
Challenges
Demand • Rapid population
growth• Globalization
Supply • Finite resource• Scarcity• Pollution and
contamination• Climate change• Desertification &
Subsidence
Demand
• 39,090 gallons to make a car• 2,847 gallons for one pound of
chocolate• 1,800 gallons to make a pair of jeans• 1,500 gallons to produce one barrel (32
gallons) of beer• 1,250-2,500 gallons for one pound of
beef • 400 gallons for a cotton T-Shirt• 5.4 gallons of water for one lumber
board
Scarcity
• Over 70% of our Earth's surface is covered by water
• 97.5% of all water on Earth is salt water, leaving only 2.5% as fresh water
• Nearly 70% of that fresh water is frozen• Remainder is mostly present as soil moisture, or
lies in deep underground aquifers• Only ~ 1% of the world's fresh water is
accessible for direct human uses.
Scarcity
• 80-100 gallons = U.S.per capita daily use
• 5 gallons = world’s poorest nations
• 1 billion people do not have access to safe drinking water.
• In African ~1/3 of population lacks access to water.
• 46% of people on earth do not have water piped to their homes
Pollution & Contamination
• 80% of sewage in developing countries is discharged untreated, polluting rivers, lakes and coastal areas
• “Dead Zones” - Globally, the most prevalent water quality problem is eutrophication, a result of high-nutrient loads (mainly phosphorus and nitrogen)
• Many industries – some heavily polluting (such as leather and chemicals) – are moving to emerging market economies
Conflict
• Protests over water shortages in South Africa turn violent
• Civilians suffer violence, intentional water cuts along Georgia-Russia border
• Farmers and herdsmen clash over land and water access - Nigeria
• Village clashes with police over spring-Mexico• Violent protests over water shortages in Egypt
Missouri Water Sources
• Surface (Rivers, lakes) – 62%– 44% from Missouri River
• 8 of 10 biggest cities
• Ground (aquifers) – 38%– High quality water– Abundant but not endless
• Cones of depression• Well interference• Cost of pumping• Saltwater intrusion• Contamination• Subsidance• Dependent on re-charge
Southwest Missouri Water Resource Study
US Army Corps of EngineersKansas City DistrictLittle Rock District
Missouri Department of Natural Resources
Regional16 County Total Supply Gap
Jan Mar
May Ju
lSe
pNov
0
50
100
150
200
250
300
Surface Water Demand
Groundwater Demand
Total Water Supply
2040
MG
D
Jan Mar
May Ju
lSe
pNov
0
50
100
150
200
250
300
Surface Water DemandGroundwater DemandTotal Water Supply
2060
MG
D
Drought Conditions
Scenario 3
Supply
Aquifers (Groundwater)• Porous consolidated rock
or unconsolidated soil• Groundwater fills spaces• Wells and pumps used to
remove water
Supply
Surface Water • Lakes, reservoirs, rivers• Rivers dammed to create
reservoirs• Reservoirs store water
during heavy rain/snow
Treatment
• Amount of treatment depends on quality of the source
• Ground water requires less treatment than surface water
Treatment
Treatment Process• Coagulation• Flocculation• Sedimentation• Filtration• Disinfection (Chlorine)• Corrosion Control• Taste & Odor Control• Fluoridation
Treatment
Chemicals• Gas Chlorine• Sodium Hypochlorite• Polyaluminum Carbonate
(PAC)• Carbon• Potassium Permanganate• Soda Ash• Fluoride
Distribution System
• Consists of water lines, fittings, valves, service lines, meters, and fire hydrants
• Loop system more desirable than branch system– Isolation valves– Water flows in more
than one direction
LOOP SYSTEM
BRANCHSYSTEM
Distribution System
• Typical new system pipe– Thermoplastic or ductile iron– Reinforced concrete in larger
mains• Older system pipe
– Cast-iron or asbestos cement• Typical distribution pressure of 65
– 75 psi• Designed for less than 150 psi• Fire Hydrants
Customer
• Residential, commercial, and industrial facilities• Residential
– Min. distribution pressure = 40 psi– Max. distribution pressure = 80 psi
• Pressure-reducing valve• Commercial or industrial facilities
– May require higher pressure– Pumps can increase pressure
• Rates
Special Thanks
Gail MelgrenExecutive Director
Tri-State Water Resource Coalition
Roddy RodgersManager-Water
Resource Projects
City Utilities