Composting Toilet at the Center for Urban Horticulture

Executive Summary:

The University of Washington Farm (UW Farm) proposes to purchase and install a composting toilet at the Center for Urban Horticulture (CUH) farm site. There is increasing need for an outdoor bathroom facility at the farm, to support student famers working and volunteering at the UW Farm, as well as other groups using the space. In 2015, there were over 180 volunteers working at the farm. In addition, the farm offered tours to over 500 UW students in 2015 alone. The lack of a bathroom on the worksite negatively impacts productivity and disrupts workflow (individuals have to stop work and leave the site to use the nearest restrooms), disrupts programing on the farm, and impedes access to any bathroom on weekends (the nearest bathrooms are locked on the weekend, a time when the farm has routine volunteer hours).

The UW Farm is hoping to attract a new cohort of visitors--school groups-- in increasing numbers to the farm.   The youth education program at the UW Farm site will face significant obstacles if there aren’t bathroom facilities in close proximity. Walking children and their chaperones and teachers to the nearest bathrooms offsite could consume a significant portion of the field trip time (as much as 30-minutes of a planned 90-minute tour), time that could be otherwise used to expose children to the concepts of sustainable agriculture and urban farming, and to inspire environmental stewardship. Given the incredible and rich educational opportunity the farm provides, it would be a shame not to be able to take full advantage of the available time.

The farm would not be the only beneficiary however. An outdoor bathroom would greatly benefit a variety of community and university groups who operate adjacent to the farm. The facility would be an indispensable resource for: community visitors to the Union Bay Natural Area (UBNA) and the CUH during daylight hours; participants in the neighboring Seattle Tilth Youth Garden Works program; youth participating in other educational programs at CUH; student ecologists and volunteers doing restoration work in UBNA; and UW grounds and maintenance members who frequently do work in the area.

In keeping with its mission to be an educational resource for people interested in learning about sustainability, the farm selected an outdoor bathroom facility that showcases green architecture, closed-loop nutrient cycling and solar energy.

Since the farm is not connected to the sewer line, a composting toilet provides an innovative and environmentally sustainable solution.  The composting system we plan to install is the M54 Trailhead single stall model produced by Clivus Multrum. This system is certified under the National Sanitation Foundation’s Standard 41 to be in compliance with health codes.  It is a completely self-contained unit, as it internally separates liquid and solid waste, breaks down solid waste, and eliminates all harmful pathogens within the tank. The system has a solar panel mounted on the roof, which provides power to the ventilation fan, ensuring an odorless and efficient environment.

We do not need to apply for a permit with the King County Department of Public Health because we will not need to excavate soil (as the tank will be placed at grade) and we will not be using the humanure on the production beds. We will not need a building permit from the city because it is a premade unit, does not need a concrete foundation, and it does not need to connect to any utility lines as the sole power source is a mounted solar panel.

Installing an advanced composting toilet system at the CUH could pave the way for similar projects to be approved within the UW and in the greater Seattle area. The Fiddlehead Forest School at the Arboretum, for example, shares the farm’s plumbing and water constraints, and plans to closely monitor the project and learn from our experience.  If the UW Farm can show that a composting toilet is a viable option and worth the upfront cost, it could enable other entities to follow the farm’s example. As novel as it may seem however, Clivus Multrum’s composting toilets are a tested, known product and a safe choice.  They have been installed throughout North America in parks, at trailheads, and even at other universities. Locally, several organizations dedicated to environmental stewardship, including Islandwood on Bainbridge Island and the Piccardo P-patch in Seattle, have installed Clivus Multrum’s composting toilets.

We are seeking funds from the Campus Sustainability Fund in the amount of of $33,000 to purchase a composting toilet and the cost of shipping.

Student Involvement:

The most direct way that this project would affect UW students is that it would enable them to work more comfortably and for longer durations at the farm and other outer lying areas at CUH. The UW Farm has countless opportunities for students to become involved and having a bathroom facility on site would enhance student’s time there as it would allow them to have a more continuous work flow and to be assured that will be provided with basic amenities during their work period. 

Additionally, students at the farm are in charge of giving tours to UW classes and to many outside visitors (in 2015, 542 students toured the farm). The composting toilet would be a highlight to talk about on such tours and would give students an opportunity to teach and discuss with their peers some of the environmental problems that this system addresses.  

Lastly, the youth education program provides tremendous opportunity for UW student involvement from building the garden, to planning curriculum, and leading the field trips. Since children are invariably fascinated with anything to do with feces, the composting toilet will provide a unique educational opportunity on the farm field trips and a lively segue to discussions of water consumption and conservation, nutrient cycling, and energy conservation.

As the UW Farm is largely student run, the entire process of planning and implementing the composting toilet will be an opportunity for student involvement. As such, this project provides students with the chance to learn about this sustainable practice from the ground up, and is a unique opportunity for hands on, interactive learning.  

Education & Outreach:

Highlights

  • Unique educational opportunity to discuss closed loop systems and water consumption
  • Engage a more diverse range of students and departments with the farm and CUH/UBNA space
  • Further UW as a leader in sustainability and innovation

Education

Having a composting toilet on campus will provide tremendous educational opportunities across various disciplines. A composting toilet addresses a number of the topics that are very relevant to current issues of sustainability, such as water usage and nutrient cycling. The composting unit is a way to add an important tangible real world example of a sustainable alternative to current practices. The compositing unit would enhance discussions about sustainability happening in various classes on campus (e.g. environmental, fisheries, and public health classes). Other potential departments that might incorporate a visit to the composting toilet would be civil and environmental engineers, landscape architects, and environmental health students. Thus this project would enable the farm to engage students who may not have a particularly strong interest in sustainable agriculture.  

For those students who do have a strong interest in sustainable agriculture, this will provide an incredible opportunity to learn about another form of composting. Composting is an essential component to maintaining soil fertility, something that is talked about extensively on the farm. Currently at the farm, we have both hot composting and vermi-composting; adding the composting toilet would further enhance learning about composting and soil fertility for students.

To maximize the educational value of the composting toilet, the farm will install informative signage to teach users and visitors about the importance of conserving water, waste water pollution, the need to create more closed loop systems, and information about how the composting toilet renders human waste into a usable, pathogen free form of fertilizer. This would increase awareness primarily within the UW community, but can also provide educational opportunities for visitors to the CUH.   

Because the UW Farm hosts tours for over 500 students, and has about 150 active service learning students, 20-30 committed volunteers, and a team of 12-15 leaders each year, this composting toilet will have a direct educational impact on the student population at UW, as well as individuals from outside the University. Since the composting toilet will be physically located at the CUH site, it will be used as an active learning tool for students working at and visiting the farm.

Outreach

The UW Farm has an extensive social media presence. If awarded this grant, we will immediately publicize the project, identifying the CSF as a funding source and Clivus Multrum as the manufacturer of the toilet. We will also at that time reach out to departments and students who might be interested in seeing the installation of the unit and/or visiting it after its completion. The farm also has a good relationship with the UWBG and the Whole U, both of whom we would approach to publicize our project in their newsletters and online presence.

We would also like to showcase our project and engage students in as many ways as possible. Ideas that we have for this include: partnering with (a) department(s) on campus and having a film screening and a series of discussions about water usage and water pollution, having a pizza bake/social event at the farm to celebrate the opening of the toilet, and table in red square highlighting current projects on the farm, with compost and water consumption as a main focus. 

Environmental Impact:
  • Energy Use
  • Waste
  • Water
Project Longevity:

As previously stated above: Dependent upon usage amount, the system usually needs to be emptied from every year to every several years. Clivus Multrum will provide this service. This system is designed based upon standard federal guidelines for restroom structures, ensuring the unit will last about 20 years. The poly compost tank is the longest lasting piece of this unit and can be salvaged and properly recycled by a city recycling facility. The rest of the unit can be disassembled and recycled and disposed of.

Environmental Problem:

Highlights

  • Requires no water to operate
  • Will not adversely impact wetlands and wildlife
  • Requires little energy inputs to maintain and has great longevity
  • Operates with solar power

Composting toilets are a sustainable solution for decreasing high volume water usage from toilets. According to the EPA’s WaterSense program, toilets are the largest consumer of indoor water usage.[1] In addition, treating wastewater is an energy intensive process, and waterways are still polluted from ‘clean’ wastewater. In a public building such as Merrill Hall (at CUH), large numbers of people are using the restrooms daily and flushing after each use.  New standard toilets use 1.6 gallons per flush, while water sense toilets use on average 1.28 gallons.1 The composting toilet that we propose to install requires no water and little energy to operate.

This system poses no threat to the nearby wetlands and its inhabitants. The UW Farm and staff members of the UW Botanic Gardens are working in collaboration with a number of individuals across departments such as Jim Morin, a Civil Engineer from Campus Engineering, and Erin McKewon and Doug Gallucchi, from the UW Environmental Health and Safety Department.  These collaborations ensure that the composting toilet system is placed in a location that is an appropriate distance from the adjacent wetlands and natural area. It will not be located in an area designated as a wetland and it will have greater than the required 200-foot setback from the shoreline.

To analyze the environmental impact of the composting toilet, usage throughout the year will be kept by use of a counter device placed in the facility. From that information, we can calculate the gallons of water saved each year. Beyond the tangible, this project would also further the CSF mission to “Create a sustainable campus and foster an environmentally conscious university culture.” Having a composting toilet on campus is an opportunity to encourage the community to think about their individual and collective water consumption and pollution caused through the normal action of flushing the toilet. Efforts like this composting toilet are an important first step in starting a dialogue among students about sustainable consumption and lifestyles.

The UW Farm has one paid staff member, the Farm Manager, and a team of student staff, as well as a student composting team, who will be responsible for maintaining the unit’s cleanliness and ensuring that it is fully stocked. The farm will also purchase and add the bulking agent (pine saw) once a month to the tank. The UW Farm staff is committed to following through on this project and ensuring that the composting toilet is well maintained. Dependent upon usage amount, the system usually needs to be emptied from every year to every several years. Clivus Multrum will provide this service. This system is designed based upon standard federal guidelines for restroom structures, ensuring the unit will last about 20 years. The poly compost tank is the longest lasting piece of this unit and can be salvaged and properly recycled by a city recycling facility. The rest of the unit can be disassembled and recycled and disposed of.

[1] http://www3.epa.gov/watersense/pubs/indoor.html

 

 

Explain how the impacts will be measured:

Highlights

  • Requires no water to operate
  • Will not adversely impact wetlands and wildlife
  • Requires little energy inputs to maintain and has great longevity
  • Operates with solar power

Composting toilets are a sustainable solution for decreasing high volume water usage from toilets. According to the EPA’s WaterSense program, toilets are the largest consumer of indoor water usage.[1] In addition, treating wastewater is an energy intensive process, and waterways are still polluted from ‘clean’ wastewater. In a public building such as Merrill Hall (at CUH), large numbers of people are using the restrooms daily and flushing after each use.  New standard toilets use 1.6 gallons per flush, while water sense toilets use on average 1.28 gallons.1 The composting toilet that we propose to install requires no water and little energy to operate.

This system poses no threat to the nearby wetlands and its inhabitants. The UW Farm and staff members of the UW Botanic Gardens are working in collaboration with a number of individuals across departments such as Jim Morin, a Civil Engineer from Campus Engineering, and Erin McKewon and Doug Gallucchi, from the UW Environmental Health and Safety Department.  These collaborations ensure that the composting toilet system is placed in a location that is an appropriate distance from the adjacent wetlands and natural area. It will not be located in an area designated as a wetland and it will have greater than the required 200-foot setback from the shoreline.

To analyze the environmental impact of the composting toilet, usage throughout the year will be kept by use of a counter device placed in the facility. From that information, we can calculate the gallons of water saved each year. Beyond the tangible, this project would also further the CSF mission to “Create a sustainable campus and foster an environmentally conscious university culture.” Having a composting toilet on campus is an opportunity to encourage the community to think about their individual and collective water consumption and pollution caused through the normal action of flushing the toilet. Efforts like this composting toilet are an important first step in starting a dialogue among students about sustainable consumption and lifestyles.

The UW Farm has one paid staff member, the Farm Manager, and a team of student staff, as well as a student composting team, who will be responsible for maintaining the unit’s cleanliness and ensuring that it is fully stocked. The farm will also purchase and add the bulking agent (pine saw) once a month to the tank. The UW Farm staff is committed to following through on this project and ensuring that the composting toilet is well maintained. Dependent upon usage amount, the system usually needs to be emptied from every year to every several years. Clivus Multrum will provide this service. This system is designed based upon standard federal guidelines for restroom structures, ensuring the unit will last about 20 years. The poly compost tank is the longest lasting piece of this unit and can be salvaged and properly recycled by a city recycling facility. The rest of the unit can be disassembled and recycled and disposed of.

[1] http://www3.epa.gov/watersense/pubs/indoor.html

 

 

Total amount requested from the CSF: $33,000
This funding request is a: Grant
If this is a loan, what is the estimated payback period?:

Budget:

ItemCost per ItemQuantityTotal Cost
M54 Trailhead pre-fab unit$28,9701$28,970
Shipping v$4,0301$4,030

Non-CSF Sources:

Project Completion Total: $33,328

Timeline:

TaskTimeframeEstimated Completion Date
Determine LocationMarch 1-4March 4
Order unitMarch 4
Receive UnitEarly April
Begin using Early April

Project Approval Forms: