Serenity: A Brief History of Toilets (and Toilet Water)

Robert E. Mace, Ph.D., P.G.The Meadows Center for Water & the Environment

Texas State Universitypresented to

16TH Annual CASE ConferenceCapital Area Suburban Exchange

South Padre, TexasJune 22, 2019

Why did I eat lunch at Taco Bell today?

Will they miss me if I’m gone for the

next 45 minutes?

•Stone Age toilets• 3100-2500 BC at Skara Brae• Orkney Islands, Scotland

photo from Toilet-guru.com

• Indus Valley• Between India and Pakistan• First known urban sanitation

system• Houses had their own toilets• Central collection via flowing

water• Almost every house had a

toilet• ~2800 BC

•~1700 BC• Egypt• Crete (Minoans)• Persia

Egyptian toilet

Crete sewer system

example from Ostia Antica

•Roman• 500 to 0 BC• Cloacina, Venus of the Sewer

•Medieval toilet

• Modern toilets• 1596: Sir John Harington

invented a flushing toilet called the Ajax

• 1775: Alexander Cumming was granted a patent for a flushing toilet with S-trap

• 1778: Joseph Bramah improved the design

• ~1880: Thomas Crapper advocated for sanitary ware; improved the S-trap

modern toilets

• Older toilets use up to 7 gallons per flush

• Federal plumbing standards require no more than 1.6 gallons per flush (gpf)

• High-efficiency single-flush toilets are 1.28 gpf

• Our toilets are 1.1 gpf

Different flavors of reuse• de facto reuse

• unplanned reuse• Indirect reuse

• planned reuse with an environmental buffer• Direct reuse

• planned reuse without an environmental buffer • “pipe to pipe”

• Sub-flavors of reuse• potable• nonpotable

de facto reuse in the

Trinity River

from NRC (2012)

Lake Livingston

• 500 million gallons per day of treated wastewaterfrom DFW Metroplex

• effluent-dominated river• 50% of normal flow• 80% in times of drought

• primary source of water (66% of supplies) for Houston

El Paso Water UtilitiesHueco Bolson Recharge ProjectIndirect Reusesince 1985

Effluent Line

Injection Wells

Production Wells

Fred Hervey Water

Reclamation Plant

Power Plant

Richland-Chambers Engineered WetlandTarrant Regional Water Districtindirect reuse

First of its kind in the United States

image from NTMWSD

Water Supply ImpactLake Lavon Yield:104,000 ac-ft/yr(93 MGD)

East Fork Water Supply Project:102,000 ac-ft/yr(91 MGD)

+

Total Yield: 206,000 ac-ft/yr(184 MGD)

+

image from NTMWSD

Direct reuse in San Antonio

Raw Water Production Facility, Big Spring, Texas

John Grant, Colorado River Municipal Water District

photo by Torin Halsey, Time Record News

“I guess that means I get to drink my beer twice…”

Daniel Nix, City of Wichita Falls, partaking of the water from the reuse project

photo by Torin Halsey, Times Record News

images from Daily WOD Wear

Micro/emerging contaminantspathogens (adenovirus, norovirus, salmonella, cryptosporidium)

Where’smy

water?

reuse in the water plan

from the 2017 State Water Plan

“Don’t drink downstream of the herd.”

• Direct non-potable• 12,000 AFY by 2040• 90,000 AFY by 2115

• Indirect potable reuse through Lady Bird Lake• 11,000 AFR by 2040• 20,000 AFY by 2115

• Distributed wastewater reuse• 3,154 AFY by 2040• 30,049 AFY by 2115

• Sewer Mining• 1,000 AFY by 2040• 5,284 AFY by 2115

• Building-scale wastewater reuse• 1,323 AFY by 2040• 7,875 AFY by 2115

• Greywater harvesting• 2,126 AFY by 2040• 12,667 AFY by 2115

AFY = acre-feet per year

Looks like I get to drink my beer

twice…

That’s more than I ever wanted to

know about toilets…