“Let’s talk about poop, baby” The day every five-year old boy dreams of…

“Let’s talk about poop, baby”

The day every five-year old boy dreams of…

Warm Up

1 True/False. Shower, sink, and toilet water leave your home through the same pipe.

2 Where does wastewater from your home go?

??

Not in here, buddy

• Developing world: human waste disposal similar to pre-modern times– Waste Ditches and cesspools– Outhouses

• 1596- John Harington designed the toilet; Thomas Crapper an early toilet maker in U.K.

• “The Great Stink” of 1858- London smelled so bad the government decided to construct an underground sewer for the city

Cesspool Design

Wastewater Treatment

• Wastewater- water that contains waste from homes or industry

• Goal of WWT- make water clean enough to return to a water source (river or lake) without damaging ecosystem

Primary Treatment

• Filtration- wastewater passed through large screen to remove solid objects

• First Settling Tank (sedimentation)- WW moved to large tank where solids settle and are later removed as sludge

Settling Tank

Secondary Treatment

• Aeration Tank- WW mixed with oxygen and aerobic bacteria to break down waste biologically

• 2nd settling tank- bacteria and other solids are removed as sludge

• Chlorination- chlorine is added to disinfect water before being released to water body

Question: What is the difference between aerobic and anaerobic?

Aeration Tanks

Tertiary Treatment

• Goal- remove anything primary and secondary didn’t remove such as:– Nutrients- Nitrogen and Phosphorus– Odor and other pathogens

• UV light• Ozone• More chlorine

Question: Why would we want to remove nitrogen and phosphorus?

Wastewater Treatment Process

What about the sludge?

• Sludge can contain toxic substances– Heavy metals: Mercury, Lead, Cadmium– Organic pollutants– Pathogens

• Where does it go?– Land: hauled to landfills– Oceans: Europe still dumps 35-45% of total vol.– Air: incinerated (burned); ash brought to landfill

Sludge Alternatives

• Fertilizers for crops• Soil conditioner (like compost)• Reclaiming a landfill for open space or park• Recycled into different materials

– Bricks– Biofuels

But...the sludge needs to be treated first to remove heavy metals and other toxins- $$

Septic Systems

• A home WWTP for rural areas• Residential wastewater flows into buried tank

on property• Solids settle in tank, liquids are distributed

throughout pipe network in soil called the “drain field”

• Soil bacteria break down liquid waste, purifies water before it re-enters the aquifer

• Sludge gets removed periodically

Septic Systems

Septic Systems1. Septic Tank2. Drainfield3. Sludge Removal

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2

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Raised septic systems for high water tables

When it hits the fan…Issues

• Unmaintained septic systems• E. Coli, fecal coliform bacteria in water

– Water-borne diseases: Cholera, Dysentary• Dumping hazardous chemicals into toilet, sink

Combined Sewer Overflows (CSOs)

• In older towns and cities, storm water and wastewater sewers are connected- all goes to WWTP

• During heavy rainstorms, WWTP cannot handle the extra load of wastewater

• So…what do you think happens?!

Georgia flooding- 2009

Untreated Wastewater in River

What can you do at home?

• Do NOT pour hazardous materials down the drain, toilet, or shower– Paint– Paint Thinner– Chemicals

• Do NOT pour excessive fats, grease, oils, or dead pets down the drain

Wrapping Up…Complete Poop Day recap before you leave

today