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Building Water Systems
Water, water everywhere, WHICH drop to drink?
Tom MeyerDirector, Technical Programs
National Environmental Balancing Bureau
Why should we worry?
Did you know?
We are all water creatures
Water makes up:
60% of your body
70% of your brain
80% of your blood
Did you know?
While you can go
almost a month
without food…
Your body can’t survive one week without water.
Did you know?
The same water that existed on Earth billions of years ago still exists today.
It covers most of the planet, but just 3% is freshwater.
And most of that is ice.
Less than 1% of all freshwater
is readily accessible for human use.
To put it another way…
Less than 0.007% of all the water on Earth is
available to drink.
(That’s one gallon in every 70,000 gallons)
Did you know?
What’s Going on With Existing
Fresh Water Supplies?
20–30% of clean water put into the local distribution system is lost before it gets to your building.
(50% if it’s an older system.)
25% of the clean water that enters your home…
…is used to flush toilets.
15% of the clean water that enters your home…
…is used at your faucets.
One toilet flush uses up to 3 gallons
One load of laundry uses up to 40 gallons
One 10-minute shower uses up to 50 gallons
Brushing with the tap running: 4 gallons
Brushing with the tap off: 0.25 gallons
Did you know?
In the 20th Century the world’s population tripled.
In the 20th Century the water use grew 6 times
Did you know?
Millions of people in the world live on less than
3 gallons each day
The average American uses about 160 gallons
Conventional Wisdom:
We are going to run out of water before we run out of oil.
Due to over-pumping, the groundwater in several
countries is almost gone.
Depleted aquifers lead to cutbacks in grain
harvests…
…which lead to more food shortages and
higher prices.
Our water problem could fast become
our hunger problem
Did you know?
Industry is thirsty…
Agriculture is thirsty…
Humanity is thirsty…
When the well is dry, we know the worth of water.
- Benjamin Franklin, Poor Richard’s Almanac, 1746
Why should we worry?
Now you know why.
This is not a future generation’s problem
This is a now generation’s problem
300-Year Drought Was Downfall of Ancient Greece- Study published in PLOS ONE
Major U.S. Cities Are at Risk for Climate-Related Water Shortage- Bloomberg
In the last five years, nearly every region of the country has experienced water shortages.
- US EPA
World Water Day: A forceful reminder that the U.S. is running out of fresh water
- The Washington Post
Freshwater Crisis- National Geographic
How do we make a finite resource meet our
needs?
Reduce Freshwater Consumption• Eliminate waste
• More efficient systems
• Use non-potable water where possible
Eliminating Waste1. Leaks/drips2. Running water until it heats up (200-300 g/month)
3. Oversized toilet tanks (oversized → 1.6 → 1.3-0.8 g/flush)
4. No flow restrictors (500 g/year)
5. Landscape irrigation (overwatering)
6. Other ideas?
More Efficient Systems
1. Toilets/Urinals 2. Flow restrictors – lavs, showers, etc.3. Machines – Washers, dishwashers, etc.4. Other ideas?
WaterSense
Overview of Water Systems
Used to be: 2-pipe system
1. Pressurized potable water - IN2. Unpressurized wastewater - OUT
Now:1. Potable water2. Rainwater3. Greywater4. Black water5. Reclaimed water
What are these different kinds of water?
Potable water
Potable waterSources
• Ground Sources – groundwater, hyporheic zones and aquifers
• Precipitation• Fresh Surface Water • Biological Sources• Seawater Desalination• Atmosphere
Non-potable water
Non-potable water
1. Rainwater2. Greywater3. Blackwater4. Reclaimed water
Purpose of non-potable water systems
To reduce the use of potable water.
Potential uses for non-potable water
systems
Rainwater
Rainwater Harvesting Catching and holding rain where it falls and using it.
Rainwater Uses
Reduces flooding, erosion and contamination of surface water with sediments, fertilizers, and pesticides in rainfall runoff.
Rainwater UsesRainwater is good for plants because it is free of salts and other minerals that harm root growth.
As rainwater percolates into the soil, it forces salts down and away from the roots zones, allowing roots to grow better and making plants more drought tolerant.
Rainwater ConcernsWater Quality
• Impurities in the air in industrialized/urban areas such as arsenic and mercury.
• Bird droppings, dust and other impurities.
• Generally, not considered potable in the US
Rainwater ConcernsWhat’s wrong in this photo?
Rainwater Uses• Lawn and Garden Irrigation• Toilet Flushing• Washing Livestock• Car Washing• Indoor Plant Watering• Pet and Livestock Watering• Evaporative Coolers
Rainwater Systems
• Simple as any container capable of holding rain from a roof or a patio with a bucket or tap
• Complex as a designed underground complex of specially designed containers with pumps
Rainwater Systems
Rainwater Systems
Rainwater Systems
Did you know?
Rainwater systems have been around for
a long, long time.
Greywater
Greywater Defined
“Wastewater collected separately from a sewage flow that does not contain industrial chemicals, hazardous wastes, or wastewater from toilets.”
Greywater Sources• Shower/tub• Laundry *• Kitchen Sink *• Dishwasher *• Lavatory Sink• Utility Sink• Swimming Pool #
• Evaporative Cooler #
NOT Greywater Sources• Toilets• Hazardous Waste• Biohazard Waste• Hazardous Chemicals• Laundry water from
Infectious garments• Laundry water from
greasy or oily rags
• Antifreeze• Mothballs• Solvents• Oils• Petroleum based fluids
Greywater Advantages
• Reduction of potable water use
• Reduction of sewer
• Available irrigation water
• Less load on septic systems
Greywater Concerns• Avoid human contact with greywater
• Avoid contact with greywater irrigated soil
• Do not irrigate food plants except citrus/nut trees
• Minimize standing greywater (no ponding)
• Do not use spray/misting irrigation – go for roots
Greywater Concerns• Plants which thrive on acidic soil should not be
watered with typically alkaline greywater
• Use greywater on well-established plants, not seedlings or young plants
• Less effluent = less reclaimed water available
• Do not store greywater unless treated first
Greywater Concerns• Accidental greywater-related illness
Number of people struck by lightning in the US per year: 400
Number of people drowned in bath tubs in the US per year: 344
Number of people with greywater transmitted illness: 0
Greywater Uses
Irrigation, toilet flushing and other non-contact uses.
Greywater Systems
Early greywater systems consisted of nothing more than a pipe going from the bottom of the sink through the exterior wall to drain out back pointed down a nearby slope.
Greywater Systems
Greywater Systems
1. Gravity-fed Manual Systems
2. Package Systems
Greywater Systems
1. Gravity-fed Manual Systems
2. Package Systems
Greywater Systems
1. Gravity-fed Manual Systems
2. Package Systems
Greywater SystemsSettling Tank
• Solids and large particles settle to the bottom• Grease, oils and small particles float• Allows hot water to cool• Should be sized to hold twice the expected daily flow
plus 40%. (65% of domestic water used is greywater)• Septic tanks are well suited for settling tanks • Aerobic type tanks provide more oxygen than septic• Pump out every 3 – 5 years
Greywater SystemsDisinfection
• Chlorine
• Iodine
Greywater SystemsFilters
• Simple as a cloth bag• Complex as a multi-media filter
Determinants• Amount of greywater• Pressurized/non-pressurized• Contaminants to be filtered
Greywater System Considerations
• How much greywater will have to be treated?
• How much area available to use greywater?
• What contaminants are present?
• What are the possible uses after treatment?
• What is the depth to water table?
Greywater System Considerations
• Soil type and percolation rate
• Climate suitable? Too cold?
• Permits required?
• Low cost/benefit ratio
• Inconvenience (high maintenance)
Greywater System Concerns• Provide for overflow into the sewer system
• Storage tanks must be covered, sealed, secured
• Stored at least 5’ above the ground water table
• Pipes must be clearly identified
• Greywater must not run off homeowner’s land
• Flush out after 24 hours or filter/treat
Greywater System ConcernsPump greywater into toilet bowl directly, unless the tank is specifically designed for greywater use.
• Could cause flushing mechanism to fail
• Possibility of cross-contamination by back-siphoning.
Blackwater
Blackwater Defined
Blackwater Uses
Untreated wastewater is 99/9% water (by weight)
Blackwater Systems• Current effluent disposal:
• Ocean outfalls• Other surface water discharges• Deep well injection
• Separate sludge from “reclaim-able” water
• Other ways:• Composting Toilet• Incinerating Toilet
Incinerating Toilet• Gas or electric powered• Burn cycle takes up to 60 min• Immediate or stored disposal• Uses no water• Produces fine sterile ash• Requires bowl liner each use
Incinerating Toilet
“I expect that properly installed, odors, noise and explosions are not an issue.”
- Buyer’s Guide to Incinerating Toilets
Further Reading• Loo and Behold! – Anurag Yadav, 2004
• Poop Culture – Dave Prager, 2007
• Flush!: The Scoop on Poop throughout the Ages – Charise Mericle Harper, 2007
• English Heritage Dictionary – Lavatorium: A communal wash area, sometimes a dedicated outbuilding or facility,
such as a basin or trough, used by monks.
Reclaimed Water
Reclaimed Water sometimes called “Recycled Water”
But ALL water is “recycled”
PURPLE PIPE
Did you know?
California pioneered water reuse for agricultural purposes in the US
dating back to 1890.
In 1912, landscape irrigation was used at San Francisco’s Golden Gate
Park.
Reclaimed Water Uses• Industrial Uses• Toilet Flushing• Agricultural Irrigation• Landscape Irrigation• Cooling Towers• Vehicle Washing• Cleaning Streets• Nurseries• Cooling Equipment
• Fire Protection• Construction Dust Control• Mixing of Pesticides• Wetlands Restoration• Flushing & Testing of Sewers • Decorative Water Features• Washing Livestock • Commercial Laundries• Concrete mix
Reclaimed Water Cannot Be Used
• Drinking• Bathing• Filling swimming pools, spas, misting• Directly on edible crops• Boiler feed water (except: extremely high quality)
Required warnings when used for irrigation
IRRIGATION WARNINGS
IRRIGATION WARNINGS
IRRIGATION WARNINGS
Reclaimed Water Systems
PROBLEMS
Hazards of more than a 2-pipe system
• Inadvertent use• Cross-piping• Contamination• Labeling problems• Equipment claims
Code Issues
– Inconsistent definitions
– Inconsistent allowed uses
– Catching up with “Green”
Review of non-potable water systems
•Rainwater•Greywater•Blackwater•Reclaimed water
Emphasis for Success• Cross-connection control • Public education • Responsible utility management • Responsive regulatory oversight • Control of pathogens • Control of organic and inorganic materials
contained in wastewater (the so-called “emerging pollutants of concern” – EPOC)
• Acceptance of a “water is water” philosophy
QUESTIONS?
Building Water Systems
Water, water everywhere, WHICH drop to drink?
Tom MeyerDirector, Technical Programs
National Environmental Balancing Bureau