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Water ReuseAmy Northam
City of LevellandDirector of Wastewater Services
WATTS ConferenceMarch 22, 2016
P.O. BOX 1010Levelland, TX 79336(806) 894-0113 ext. 263(806) 470-7810 [email protected]
Water is needed for life.
∗ Every creature and plant on Earth needs water to survive.
∗ Oceans make up about 97% of the Earth’s water.
∗ Less than 1% is available to people for consumption, agriculture, and industry use.
Feinstein, 2011 p. 9
Water on Earth
Oceans 97% Snow and Glaciers 2%
Fresh Water 3% Rivers, Lakes, Streams 1%
Conservation and Water Reuse needed to promote sustainability.
∗ 2005 US average use per household is 254 gallons per day (48,000 MGD).
∗ Installing home water-saving features, water use would decrease by 30%.
∗ 2005 US Industry use 162,000 MGD
∗ Switching to closed-loop recirculation cooling towers would save 50% or more water use.
Source: World Bank Freshwater Table 3.5
0%
20%
40%
60%
80%
100%
World US
7040
18
46
12 14
2011 Freshwater Withdrawals
Domestic
Industrial
Agriculture
Source: AWWA Water Use Statistics 2014, USGS 2005 Estimated Water Use 2009
Conservation and Water Reuse needed to promote sustainability.
∗ 2005 US Agricultural use 138,000 MGD per day; half is lost to evaporation and evapotranspiration.
∗ Switching to low flow irrigation would save 35% from evaporation:∗ Drip Irrigation∗ Low Spray Irrigation
Source: World Bank Freshwater Table 3.5
0%
20%
40%
60%
80%
100%
World US
7040
18
46
12 14
2011 Freshwater Withdrawals
Domestic
Industrial
Agriculture
Source: USGS 2005 Estimated Water Use
Early Examples of Water Reuse.
∗ The oldest use of reclaimed wastewater in the US is in Grand Canyon Village, AZ IN 1926. ∗ Dual distribution system - two separate lines into a
residence, to supply water for:∗ Toilet flushing ∗ Boiler feed water for power generators ∗ Steam locomotives (Fulton 2011, p.12).
Early Examples of Water Reuse.
∗ Agricultural – non food crops∗ Industrial – thermoelectric
cooling towers∗ Irrigation - lawns, golf
courses, and parks
By the 1970s, several other cities began reusing their wastewater for:
Early Examples of Water Reuse.
In 2008, the US reuses the most reclaimed wastewater out of all countries at a rate of 2 BGD (Jimenez, 2008; NRC, 2012).
0 1,000 2,000 3,000 4,000 5,000 6,000
USASaudi Arabia
EgyptSyria
IsrealSpain
Total reuse
2,006488470
268217203
5,416
MGD
Brackish Lagoons Oceans Treated Wastewater
Where can we reclaim water for reuse?
Image Source: brackish.usegrid.net Image Source: kevinalanlamb.com Image Source: www.kfactorfilter.com
(U.S. Environmental Protection Agency & USAID 2012)
Potable Reuse
∗ Most familiar & sanitary∗ Strict treatment
requirement for health∗ For human consumption∗ Public water works∗ Bottled water
Potable
Drinking
Bathing
Cooking
Non-potable Reuse
∗ Known as ‘gray water’∗ Treatment not as strict∗ Agriculture
∗ Irrigation of non-human food crops
∗ Industrial∗ Cooling Towers∗ Mining∗ Paper Processing
∗ Urban∗ Fire hydrants∗ Lawn and park irrigation∗ Toilets∗ Boiler feed
Non-potable
Agriculture
Industrial
Urban
Defacto Reuse
∗ Discharge from a municipal treatment plant to a stream or reservoir
∗ Travels downstream mixing with storm water to another lake or reservoir
∗ Pulled from downstream lake or reservoir for reuse
∗ Example: Trinity River, CRMWADefacto
Discharge
Reservoir
Reuse
What Can We Do to Reclaim Water from Sewage and Reuse It?
Primary • Remove large solids, grit, & grease
Secondary
• Biological & chemical process to break down nutrients and remove most solids
Tertiary• Polishes and
disinfects water
Treatment Process to Remove Wastes
Wastewater Treatment for Reuse
Image Retrieved from: http://eschooltoday.com/pollution/water-pollution/sewage-treatment-process-for-kids.html
