composting toilets workshop - engineers without borders symposium, davis ca october 2014

Compos'ng Toilets: Overview and Hands-‐on Workshop

Pat Coyle, SFP ATDT lead for

The 1st Symposium Without Borders October 25, 2014

Agenda •  Background – the need •  Benefits/Advantages •  Safety •  Some organiza'ons involved •  Overview – types, examples: •  Household or school: with in-‐vault or on-‐site compos'ng •  Urban: sanita'on-‐as-‐service, with off-‐site compos'ng

•  Specific case: SFP-‐ATDT Compos'ng Latrines in Nicaragua •  Hands-‐on workshop: based on A Sewer Catastrophe Companion: Dry Toilets for Wet Disasters, the field-‐proven 5-‐gallon pail based composAng approach for seismic or other emergency response situaAons

Background – the need Over 2.6 billion people don’t have access to toilets with huge health consequences: •  Open defeca'on and improperly maintained, overflowing latrines contaminate drinking water and food supplies •  The resultant cholera, hepa''s, parasites such as hookworms and other microscopic nas'es claim lives, sicken people and cripple economies by keeping people home from school and work. 1.8 million people die every year from diarrheal diseases, and 90% of these are children under the age of 5

•  Safety -‐ Lack of toilets puts women at risk. In India in May 2014, two young girls were a_acked, raped and le` hanging from a tree. The deaths could have been prevented if the girls had access to a toilet at home. Lacking one, as millions do, they went to an open field to relieve themselves

Benefits of compos'ng toilets Compos'ng toilets have clear ecological and economical advantages over flush toilets. In addi'on to addressing the sanita'on issue, they: •  turn waste into compost. The compost can fer'lize crops, comple'ng a circle of nutrients that saves and rebuilds soils and saves money •  save money in the costs of sewage disposal and in fer'lizer •  require much less water and energy

Cell phone analogy -‐ some developing countries have skipped land lines, moved directly to cell phone networks Similarly, they could skip the water and energy intensive sewer treatment approach -‐ and instead, rely on dry sanita'on compos'ng solu'ons

Managing Poop Safely When is the compost containing poop safe to use on an annual Garden? (from A Sewer Catastrophe Companion with references) •  Op'on 1: Reten'on -‐ Retaining compost can kill many pathogens by keeping pathogens away from their host (our gut), however, Ascaris eggs (roundworm) can last up to 130 days and s'll be viable. Retaining compost for two years (730 days) is considered extremely safe •  Op'on 2: High Temps -‐ Most pathogens are adapted for a narrow temperature range around their host’s body temperature, and very few survive outside of that range. Two consecu've days at 57°C (135°F) kills roundworm eggs. Federal guidelines for sewage sludge treatment require three days at 55°C (131°F) for pathogen reduc'on

Managing Poop Safely (cont.) • What are the Risks of Compos'ng Here in the US? Depends on what crops you’re using it on. If you’re just burying it in the soil near trees and bushes the risks are negligible. If you’re using it on annuals you should make sure you can guarantee pathogen destruc'on before use. In the US parasites are not as common as in other places in the world •  No treatment is guaranteed safe, but the most complete decomposi'on happens when the widest variety of decomposing organisms expose the material to the greatest number of extreme environments •  Diversity is the key to the safety and broad effec'veness of compos'ng against pathogens and organic pollutants

Managing Pee Safely •  Urine Disease Risks: In healthy people urine is sterile, although it may pick up bacteria or feces while leaving the urethra. Those with severe kidney and bladder problems may transmit infec'ons through blood contaminated urine. Urine from a person with kidney problems could contain blood which might contain hepa''s A & B, CMV, JCV and BKV (flu-‐like viruses), albeit at low levels with a low risk of infec'on •  Addressing Urine Disease Risks: When retained outside the body, the urea and water in urine quickly change to ammonia and then ammonium during reten'on, raising the pH from around 7 to around 9. The pH change and presence of ammonia (which is toxic to all living cells at high concentra'ons) is enough to inac'vate most bacteria within 2 hours

Managing Pee Safely (cont.) •  Reten'on of urine at 20° C (68°F) for 6 months reduces the risk of pathogen exposure to negligible (10 to 15 logarithmic reduc'on) for bacteria (C. jejuni), protozoa (C. parvum) and viruses (Rotavirus) found in feces that may be present in collected urine •  A`er urine is applied as a fer'lizer to fields, pathogen inac'va'on con'nues from UV-‐radia'on and exposure to soil biota •  Simple UV steriliza'on or aerobic co-‐compos'ng of urine is an addi'onal treatment op'on •  In Sweden, urine is used as a fer'lizer for any crop a`er a one month reten'on at 20° C (must be applied one month before plan'ng for crops that are to be eaten raw)

Killing the Tough Bugs

Killing the Tough Bugs (cont.) Roundworm eggs are one of the most difficult pathogens to eliminate. •  Roundworm eggs are larger and have classically been easier to detect than other hard-‐shelled pathogens, such as spore-‐forming bacteria •  Human and pig Ascaris are used as “indicator” organisms, introduced to evaluate a processing technique alongside common indicators fecal coliform and Salmonella •  Low levels of indicator pathogens denotes effec've treatment of a range of pathogens

Some major organiza'ons involved

Overview – types, examples

SOIL, Sustainable Organic Integrated Livelihoods, developed EcoSan latrines that store human waste in removable 15-‐gallon drums for compos'ng. SOIL and its partners build and manage latrines, compost centers and vegetable gardens and hold sanita'on workshops in Port au Prince

Resource blogged; cartridge-‐based sanita'on services…have tremendous poten'al, but to reach that poten'al we need to make them much, much bigger…more than 748 million people live in ci'es today without access to decent sanita'on, and that number grows every day. We need to move from serving thousands of people…to hundreds of millions…We’ve been hard at work on several fronts -‐ hardware development, so`ware development, and impact evalua'on – all cri'cal for urban sanita'on services to scale

Concept: ultra-‐low-‐cost toilet using removable containers

•  Easy to collect and transport wastes safely from the community •  A good toilet is a symbol of cleanliness and modernity •  Beyond being odorless, hygienic, and vector-‐free, toilet needs to be elegant, modern, and pleasant to use •  It needs to be cheap. Toilet combines a 20-‐L bucket, a liquid container, and a western-‐style toilet seat into a sealed, portable, urine-‐diver'ng toilet

Resource: Strategy •  Strategy is to collect and deliver the wastes to SOIL’s exis'ng compost sites, where the wastes will be converted to valuable compost for sale to agricultural and reforesta'on customers •  Given limited road access and a popula'on density too high for on-‐site treatment, use two-‐step collec'on process •  First, full containers are removed from the homes and replaced with clean ones •  The containers are transported in carts or dollies from homes to collec'on centers, where they are then transferred to trucks for transport, processing, and cleaning at the compost site •  Sell the compost to help finance the service, and help restore Hai'’s devastated soil

Resource: full cycle •  Collect and deliver the wastes to SOIL’s exis'ng compost sites •  Remove full containers, replace with clean ones •  Transport containers, carts to trucks •  Compost waste, clean containers at the compost site •  Sell the compost to help finance the service, restore Hai'’s devastated soil


X-‐runner is opera'ng sanita'on as a service to low-‐income, urban households that cannot have regular toilets in Lima, Peru where 3 million people don’t have a toilet at home and use latrines


Clean team, in Ghana, offers an innova've, affordable sanita'on solu'on for low-‐income communi'es in the developing world


Sanergy builds healthy, prosperous communi'es by making hygienic sanita'on affordable and accessible throughout Africa's informal se_lements


From 525, Portland Maine Professionals, (Portland State University) For Ethiopia, Debre Birhan School Sanita'on project


From 525, UNIVERSITY OF NEVADA, LAS VEGAS PROFESSIONALS, NICARAGUA, SAN FRANCISCO LIBRE, LOMAS DEL SOL SANITARY IMPROVEMENT PROJECT


(Cont.) From 525, UNIVERSITY OF NEVADA, LAS VEGAS PROFESSIONALS, NICARAGUA, SAN FRANCISCO LIBRE, LOMAS DEL SOL SANITARY IMPROVEMENT PROJECT

Specific case: SFP-‐ATDT Compos'ng Latrines in Nicaragua

•  In 2010, EWB-‐SFP ATDT, Alvarez Co-‐op, Alcance Nicaragua (AN) and Outreach Interna'onal (OI), built ten compos'ng toilets with the community of Los Alvarez, Nicaragua (134 families, ~ 938 people) •  95% of its latrines were in poor condi'on. These latrines flood with water during the winter and fail structurally, resul'ng in illnesses due to exposure to fecal ma_er and water contamina'on •  The environment is polluted and inhabitants are exposed to physical harm due to latrine collapse

Completed compos'ng toilet from 2010 pilot implementa'on trip

Phase 1 •  In April 2010, EWB-‐SFP visited Los Alvarez for an exploratory trip •  The design selected, with the input from the community, was a two-‐compartment compos'ng latrine that would allow one compartment to be sealed during the compos'ng process •  Planning and material procurement took place between October-‐December 2010 •  Construc'on took place in January 2011 and ten compos'ng latrines were built • Workshops were conducted on the use and maintenance of the compos'ng latrines •  blog: h_p://compostnica.wordpress.com/

Compos'ng Latrine Status •  The first compos'ng toilets are working great •  User acceptance has been high •  Genera'on and use of compost for agricultural applica'ons has been successful •  The community wants more units

Phase 2 Planning •  A member of the Alcance Nicaragua designed and built a “hybrid” compos'ng toilet which decreased the cost by half, to approximately $300 per toilet

Prototype reduced cost redesigned toilet

Phase 2 Planning (cont.) •  Goal: build fourteen compos'ng toilets in El Llanito community using the new design ($336/toilet) •  Alcance Nicaragua responsibili'es: materials procurement and transporta'on, iden'fying new beneficiaries, managing the construc'on, and collec'ng beneficiaries’ contribu'on (40% of cost)

Phase 2 Planning (cont.) •  July 2014: AN selects par'cipants •  August 2014: Material Procurement prior to construc'on start •  August 19-‐August 31: Construc'on •  Post Construc'on: •  Documenta'on

Phase 2 ConstrucHon

Preparing founda'on

Phase 2 ConstrucHon (cont.)

Concrete in founda'on form


Building the vaults


Sealing the vaults with plaster coat


Building the upper structure


Families with completed toilets

Families a`er workshop

Hands-‐on workshop Based on A Sewer Catastrophe Companion: Dry Toilets for Wet Disasters, the field-‐proven 5-‐gallon pail based composAng approach for seismic or other emergency response situaAons

Hands-‐on workshop (cont.)

Wrap-‐up, Q&A The simple way to think about this is “Don't poop in the water.” Ques'ons? Email me, [email protected], with follow up ques'ons and for a copy of the Sewer Catastrophe Companion: Dry Toilets for Wet Disasters, the field-‐proven 5-‐gallon pail based composAng approach for seismic or other emergency response situaAons … or you can find it online at: h_p://www.portlandoregon.gov/pbem/ar'cle/447707

composting toilets workshop - engineers without borders symposium, davis ca october 2014

Engineering