Composting Toilets and Beyond

Roman Latrine in Ostia, Italy

Managing feces and urine has been a focus of civilizations for thousands of years. All over the world people have developed systems from as simple as digging a hole in the ground, or using running water to carry it away to a river or stream, to complex interconnected cities of underground pipes that end in sewage treatment facilities. In Asia it is common to recycle feces and apply it back to agricultural ground as “Night Soil”, while in America and Europe it is commonly referred to as “Waste” and thought of only in disgust. Feces and urine definitely should be considered carefully, as feces in particular can harbor dangerous or potentially lethal viruses and bacteria. Handled properly, however, human as well as other animal “Waste” can be recycled through the various processes of nature or applied science.

Chamber Pot - Nottingham, England - 16th - 18th Century

Advancements in sanitation and hygiene practices are often cited as an integral factor of recent global population boom. Modern western plumbing employs a drain-waste-vent system removing sewage and greywater from a building and venting gases produced by the waste. Running water carries away the waste and joins with a central sewage system often leading to a central sewage treatment plant and eventually a landfill. As the population continues to rise, the feasibility of using more water and land to divert human waste will become more difficult and ultimately fall on the shoulders of a future generation to determine how to reclaim these currently untapped unwanted resources. Over one billion people currently live without consistent access to running water or electricity. Composting toilets offer one alternative, but not without their own drawbacks, and further advances in environmental engineering and chemical engineering are allowing for greater technological advances in the capture and processing of human waste.

Drain-Waste-Vent System

Composting Toilet

The compost toilet can either collect urine and feces together or separately. If collected separately, the urine may be used directly as fertilizer or channeled into a small wetland or marshy plant bed to evaporate or be absorbed. Feces collection can be as simple as using 5 gallon buckets and swapping them out as the buckets are filled. Some composting toilets have two or more large collection chambers and when one is full it is closed off while the second chamber is then used for collection. The closed collection chamber often remains sitting for a year or more before being used as compost. Generally the smaller the chamber for collection there is more likely a greater need for a separately located compost pile.

5-Gallon Bucket

Double Chamber Compost Toilet

Some composting toilets try to employ external heat, either via the sun or electronic heating systems, to dehydrate the fecal collections. The dehydrated feces often need additional composting to be made useable. Every year the Bill and Melinda Gates Foundation offer a competitive grant to groups designing innovative toilets requiring no running water or externally generated electricity. The winning group in 2014 is from the University of Colorado Boulder 2014 and was awarded $770,000 for a design that uses concentrated solar energy to convert collected feces into biochar.

Solar Composting Toilet

"Biochar" Toilet

Whether you use a simple 5-gallon bucket to collect your human waste or a high tech solar toilet to convert into biochar, the design of the modern toilet will eventually have to change. Fresh drinkable water is a precious resource that should eventually be excluded from human waste management. The composting toilet provides the opportunity to turn human waste into fresh vegetables.

Merritt College land/hort outdoor kitchen facelift

 

Out door kitchen revival

This project has been a great collaboration with most of the class, if not all the students. Carlos and I have seemed to be the two more dedicated and decided to use this experience as our research project.

            When beginning the planning stages of the kitchen revival, we had ideas ranging from cabinet doors, new shelving, bamboo hanging racks, window retrofit, new plaster etc… We decided to focus on a realistic goal and that was to level the ground, create some kind of floor and fabricate cabinet doors for under and around the sink and storage areas.

Raising and leveling the floor

            When we were ready to raise the floor we decided that it made sense to raise it and level it to the existing concrete foundation, which were the four corners of the kitchen. We first needed to pull out the existing shelf to gain access to the entire floor space. Then we started filling it in with decomposed granite from onsite with about 1-2 inch layers, wetting each layer and then tamping each layer level. It took about a dozen wheelbarrow loads to get up the 6 inches or so we needed to meet the foundation pillars. We left a bit of room for bricks to be laid under the counter space so that the brick would be level with the rest of the floor and foundation. We also cut 2X4’s and secured them with rebar to hold the DG and bricks in place around the uneven sides of the perimeter. After the floor and bricks we secure and level we could move on to planning the cabinet doors and frame.

Cabinet frame and doors

Since the space under the counters where the doors were planned to go was void of any structure to secure doors we needed to build a frame. We came to the conclusion to use 2X4’s for the frame and the door frames because we felt there were enough on site and this would make for a durable end result. The frame itself would be two rectangle frames tied to the existing structure and to each other at the 90 degree angle in the middle. Depending on the rigidity of that structure we would see if it needed to be further reinforced with corner braces. Carlos already started building the door units as we planned the frame and cut the lumber. With the area we had it made sense to have two doors on the left side and three under the sink area, since it was longer. The doors were made into frames with a open center to later be filled with bamboo. The areas were measured and the door lumber was cut then biscuit jointed and glued together. Once the glue was dry we used a router on the backside of each door to create a recess for installing bamboo inserts.

More to come....

The effects of commonly-used stone for landscaping

These photos are of a job I worked on throughout this past spring for a few months. I was amazed on the amount of stone we imported to the site. The final product has a very natural look on the surface, but I became inspired to find out what it actually takes to get these beautiful stones from their birthplace to our walls and patios. 

The first effect that occurred to me is the amount of fuel it takes to get from Connecticut, which is where the flagstone we used on this job came from. Connecticut is about 3000 miles from the S.F. Bay. Diesel semi-trucks get about 5 mpg. That equals about 600 gallons of diesel fuel used for a full truckload a stone. We used about 1/2 truckload of Connecticut bluestone (sandstone, flagstone) for this job.

The majority of the stone we used, including the walls, stairs, waterfall, and boulders, are Napa basalt. We received about two semi-truck flatbeds full of this stone. Considering Napa isn't to far from the job site, diesel fuel wasn't a big concern to me, but environmental habitat loss and the mining process was.

My next step is to visit one of the quarries in operation in the Napa and St. Helena area. I want to obtain an environmental impact report as well. It has been difficult finding info on these quarries and I assume visiting one may be a tough task, but I assume an in-person experience will help get the facts I seek.

http://www.dec.ny.gov/lands/5025.html

Above is a photo of a mining operation in N.Y. I want to find out about how permits are obtained for blue-stone mines. This sandstone was formed in the Devonian Age, only a few hundred million years ago. 

West Coast Indigenous Building

People indigenous to West coast Northern America were of many different groups and tribes. The Chumash people lived all throughout Malibu to Paso Robles California. Their houses were made from willow branches formed into domes and sometimes used whale bones for support. Tule reed or cattail mats were used for roofs. A small hole was left in the top for air circulation and covered with a skin when it rained

Sweat houses were built partially underground and usually had openings in the top with a ladder for access. Ohlone people of the Bay area made similar structures with access from the side.

Tule reeds were used for many things by Bay Area native people. Boats were very boyant with Tule construction because they were hollow, light and airy.

Pueblos

by degani

Pueblos

 In my paper I will explore the types of housing used by the Hopi and the Navajo first nation tribes of the southwest United States. The main focus will be on Adobe dwellings which provided a thermal mass, connection to their spirituality and protection. I will talk about who the tribes were and what their lifestyles were like so that a picture could be painted about their Pueblos.

les toilettes seches

Compost Toilets

Water is a precious resource. So why are we flushing it down the toilet? 

At home, we often use our pee to help our plants [pee-pee ponics].

As I showed in my 'precedent' blog post, I have seen quite nice compost toilets that exist & I believe trump misconceptions about dirtiness or smell or lack of beauty.

Pee pee + add a little bit of hose-water = happy plants

Often highly-regarded reference book on compost toilets

Building Codes

I plan to look into California & local codes for having compost toilets:
http://www.composting-toilet-store.com/Building_Codes_Regulations_s/107.htm

Alternatives

Human waste + Anaerobic digestion = Biogas + Fertilizer

Anaerobic digestion (AD) is a biological process in which organic waste is consumed by micro-organisms in oxygen-free environments. It is used for industrial or domestic purposes to manage waste and to release energy. As it decomposes, the waste releases biogas.

Biogas is composed of methane (CH4, 65%), carbon dioxide (CO2, 33%) and other trace gases (2%). For comparison, the natural gas supplied to ordinary gas stoves and boilers is about 80% methane. When biogas is burned, the methane converts back to CO2 and water vapor, so the gas is clean burning.

Fertilizer is the other by product of AD. The microbial process homogenizes the nutrients making them easier for plants to access. The output is a semi-liquid manure that is easily separated into liquid plant food and fiber-rich manure that’s perfect for digging in under newly planted crops.

(Sourced from) http://www.loowatt.com/digestion/

For a video that explains how to make your own bio-digester:
http://theurbanfarmingguys.com/methane-biodigester-how-to