“Rainforest Ecology and the Natural History of Costa Rica”
Honors in Costa Rica Summer 2006
A Final Report
By Leanne Do
Introduction
I
n the middle of a regular college quarter, three weeks can fly by. Filled with classes, assignments, midterms, and the million other obligations of college life, the comfort of routine can make life pass at an alarming speed. But three weeks spent in a foreign country learning about a foreign topic can drastically slow the pace.
Since my freshman year, I’ve known that studying abroad is something that I both want and need to incorporate into my undergraduate years. Because of budgetary restraints, spending an entire quarter abroad wasn’t an option for me. By most measures, three weeks to study abroad seem awfully short. But when those three weeks are packed with enriching educational experiences, they seem much longer, deeper and fuller than any three weeks I could have spent in a traditional classroom.
The Honors “Rainforest Ecology and Natural History of Costa Rica” program was three weeks full of excitement, challenge, enrichment and fun.
I learned a tremendous amount about myself and the world while in Costa Rica, much of it related to my three aims for the trip:
Aim #1: Engage with the natural history and natural environment of Costa Rica
Objectives:
-Take exploratory hikes both in the daytime and nighttime
-Observe and identify animal and plant life in their natural settings
Aim #2: Study sustainability through the use of composting toilets at Rancho
Mastatal
Objectives:
-gain a basic understanding of how composting toilets work
-understand the significance and ecological impacts of the two composting toilets at Rancho Mastatal through interviews, independent research and an on-site study
Aim #3: Experience the rich culture of Costa Rica
Objectives:
-Participate in an overnight homestay at the village Mastatal
-Interact with the locals of Costa Rica
Costa Rica is the ideal place to study the environment because of its rich ecology. In our time there, we were able to visit a Pacific lowland rainforest, a Pacific beach ecosystem, and a cloud forest on the continental divide, each place unique and unlike the others. The country is likewise an ideal place to experience a new culture because of the richness of its people. In our three weeks, we experienced rural life but also life in tourists towns and we made a stop in a fairly major city. Finally, this particular program was optimal for studying sustainability because it took us to a one-of-a-kind sustainability educational center where we learned and lived the meaning of sustainability.
For my independent project in Costa Rica, I chose to study the composting toilets at Rancho Mastatal as a focal point for gaining a broader understanding of sustainability. In the next section, my formal report on the Rancho Mastal composting toilets will detail this experience further.
Project Write-Up
Sustainability Through the Use of Composting Toilets
A Formal Report
By Leanne Do
Independent Study Formal Report
Sustainability Through the Use of Composting Toilets
Abstract: Composting toilets conserve water and convert waste into usable nutrients. The Rancho Mastatal environmental learning and sustainable living center operates three composting toilets, in addition to several flush toilets. This study looked at the two composting toilets and two flush toilets associated with the Jeannie’s House and the Main House sites at Rancho Mastatal. Through an interview, tally and survey, the study aimed to understand why and how these toilets were used by our visiting group. The data indicated that while flush toilets were frequented more often overall, the purposes of use as well as the time of day of use of the toilets were important factors relating to the type of toilet used.
Introduction
When you finish with something, throw it away. In the world I grew up in, that was considered common sense. But in the world I’ve discovered since college, it’s become quite the opposite.
“The idea of waste, of something unusable, reveals an incomplete understanding of how things work. Nature admits no waste. Nothing is left over; everything is joined in the spiral of life” (Van der Ryn, 5).
Before going to Costa Rica, it had never occurred to me to consider human waste as anything more than waste. But the composting toilets at Rancho Mastatal have made me think otherwise. By taking what we consider waste (urine and feces) and allowing it to turn naturally into a resource (a nutrient-rich soil additive called humus), composting toilets take the concept of recycling to a whole new level.
Or perhaps, it’s a whole old level, an old idea, a biological idea, and one that we’ve strayed away from. In the food cycle, we take food from the ground, grown from the earth. To complete the cycle, we ought to put the end product back into the ground, back onto the earth. But where does it go instead? In the system I grew up with, it goes into water. It is flushed away by drinking water to become someone else’s problem.
“Excreta is one of few substances of material value we ever return to the earth. Our body waste is truly a resource out of place” (12).
Some societies have known this for centuries. In China and Japan, farmers have historically collected humanure (a term for human excrement that highlights its potential as a resource) to fertilize the fields (12). In a recent conversation with my father about composting toilets, my father recalled how in his impoverished childhood in rural Vietnam, he would make extra money by excreting onto a small pan, collected by a local woman to be used as fertilizer.
Though in my father’s upbringing, spreading humanure onto plants was not feared, it would be today. Fear of disease is a major concern and a major roadblock to seeing humanure as a resource. But if composted correctly, humanure becomes humus, which can safely be used as a soil enricher for non-edible plants (38).
The end product collected from the composting toilets at Rancho Mastatal is used for this purpose and is no doubt a large contributor to the beautiful ornamental plants that help lend the center its unique and tropical character.
“It is possible to quit putting our so-called bodily wastes where they don’t belong (in the water) and to start putting them where they do belong (on the land). When waste is used, a liability becomes an asset, and the very concept of waste disappears. All this, of course, is the commonest of common sense” (10).
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The main purpose of my on-site study of composting toilets at Rancho Mastatal was to explore the purpose and use of the composting toilets. I aimed to examine when and why they were used, as well as gauge reactions to them, with the hope of gaining a better understanding of the role they play at Rancho Mastatal.
Methodology
The on-site research of the Rancho Mastatal composting toilets consisted of three parts:
1. Interview with Tim
The purpose of the interview with Tim was to understand the history and philosophy behind the use of composting toilets at Rancho Mastatal, as well as to understand how the toilets function. The interview consisted of 32 questions and was conducted on our second academic day at Rancho Mastatal.
Please see Appendix for interview questions and typed notes on the interview.
2. Toilet Use Tally
The Toilet Use Tally was originally intended to compare the frequency of use between the composting and flush toilets at Rancho Mastatal by our visiting group over a five-day segment of our stay. For that reason, the original tally sheet only recorded toilet uses for each of our five academic days. Once on-site, many adjustments were made to the original tally sheet to deepen my research. The final Toilet Use Tally recorded the location of the toilet, the type of toilet, the purpose of use, the time of day of use, and the amount that the flush toilets were flushed.
To reach this finalized Tally sheet, I had to make several revisions to my original document.
First, I decided to limit the location of my study to two areas of the ranch: 1) Jeannie’s House, where the majority of our group was staying, AND 2) the Main House, where we had most of our meals and spent much time. Each of these locations had both one composting toilet and one flush toilet. Thus, visitors at these two locations had to choose between using either a flush toilet or a composting toilet each time they needed to use the toilet. I did not study the third composting toilet on site, located at La Chosa, because it did not have a nearby flush toilet that I could compare it to.
Second, I decided to record for what purpose the toilets were being used. Before I began my study, Robin pointed out to me that some people may make a point to use a certain type of toilet for a certain type of purpose. To measure purpose then, I divided my tally sheet into two columns, with column one representing urination, and column two indicating defecation or both defecation and urination, in relation to the euphemistic terms “going #1 or #2.”
Also before I started my study, I realized another factor that might affect a person’s decision to use either a composting or flush toilet. After becoming familiar with the location of the four toilets in my study, I realized that the time of day could be a factor in a person’s use of the toilets. The two flush toilets were both located inside, while the composting toilets were located behind and away from the main structure. That meant that at night, a person who wanted to use the composting toilets would have to walk along a dark trail to use the toilet, versus staying inside to use the flush toilet. To gauge whether or not this would make a difference, I requested that visitors mark their toilet uses on the tally sheet with either a “D” or an “N” to indicate whether they had used the toilet during the day or at night. For my purposes, daytime referred to when it was light out and nighttime to when it was dark.
Fourth and finally, Robin again astutely pointed out another factor that I had not considered before arriving onsite. At the Rancho Mastatal orientation, Tim encourages visitors to save water by flushing only when necessary. Thus, visitors may use flush toilets for urination multiple times before flushing. When seeking to understand how much water is saved by using composting toilets versus flush toilets then, it’s necessary to recognize that not all toilet uses represent toilet flushes. So I asked my tally participants to circle their tally if they flushed the toilet, so I could better assess how much water was actually flushed away during our stay.
Hence, the Toilet Use Tally considers the following factors:
1)Location (Jeannie’s House or the Main House)
2)Type of toilet (composting or flush)
3)Purpose of Use (#1 or #2)
- #1 = urination
- #2 = defecation or both urination and defecation
4)Time of Day of Use (daytime or nighttime)
Note: For the purposes of my research aim, the purpose of use and time of day of use are only relevant in relation to the type of toilet used. In other words, my research question asked: Does the purpose of use or the time of day of use affect what sort of toilet is used?
Please see Appendix A for the original Toilet Use Tally sheet. Please see the attached PDF file for scanned images of the actual Toilet Use Tally sheets used on-site.
3. Toilet Preference Survey
The final part of my onsite research consisted of a Toilet Preference Survey administered to the members of our school group. The purpose of this survey was to gain a sense of people’s reactions to and thoughts on the composting toilets. My hope was also to use the surveys to explore possible explanations for the toilet use observations I made.
Please see Appendix for a copy of the Toilet Preference Survey. Please see the attached PDF file for scanned images of the completed surveys.
Results
1. Interview with Tim
Please see Appendix for the typed interview notes.
2. Toilet Use Tally
Please see the tables and graphs below.
3. Toilet Preference Survey
Please see the attached PDF file for scanned images of the completed surveys.
DATA TABLES
i. Comprehensive Tables
Figure 1.1Jeannie’s House Toilet UsageComposting toilet / Flush toilet
#1 / #2 / #1 / #2
Day / Night / Day / Night / Day / Night / Day / Night
Day 1 / 13 / 0 / 7 / 0 / 14 / 2 / 1 / 0
Day 2 / 12 / 0 / 12 / 0 / 15 / 3 / 1 / 0
Day 3 / 9 / 0 / 7 / 0 / 20 / 15 / 1 / 3
Day 4 / 6 / 1 / 6 / 0 / 14 / 7 / 2 / 1
Day 5 / 6 / 0 / 7 / 0 / 8 / 10 / 3 / 0
Week Total / 46 / 1 / 39 / 0 / 71 / 37 / 8 / 4
Figure 1.2 Main House Toilet Usage
Composting toilet / Flush toilet
#1 / #2 / #1 / #2
Day / Night / Day / Night / Day / Night / Day / Night
Day 1 / 4 / 0 / 2 / 2 / 14 / 7 / 1 / 0
Day 2 / 1 / 0 / 7 / 0 / 20 / 7 / 1 / 0
Day 3 / 0 / 0 / 4 / 0 / 5 / 5 / 1 / 0
Day 4 / 0 / 1 / 6 / 0 / 3 / 6 / 2 / 0
Day 5 / 3 / 0 / 3 / 1 / 13 / 5 / 0 / 2
Week Total / 8 / 1 / 22 / 3 / 55 / 30 / 5 / 2
Figure 1.3Total Toilet Usage by Location
Jeannie’s House (2 toilets) / Main House (2 toilets)
Day 1 / 37 / 30
Day 2 / 43 / 36
Day 3 / 55 / 15
Day 4 / 37 / 18
Day 5 / 34 / 27
Total / 206 / 126
Figure 1.4Total Toilet Usage by Type
Composting (2 toilets) / Flush (2 toilets)
Day 1 / 28 / 39
Day 2 / 32 / 47
Day 3 / 20 / 50
Day 4 / 20 / 35
Day 5 / 20 / 41
Total / 120 / 212
ii. Type and Purpose of Use Tables
Figure 2.1Jeannie’s House Toilet Usage by Type and Purpose of Use#1 / #2
Composting / Flush / Composting / Flush
Day 1 / 13 / 16 / 7 / 1
Day 2 / 12 / 18 / 12 / 1
Day 3 / 9 / 35 / 7 / 4
Day 4 / 7 / 21 / 6 / 3
Day 5 / 6 / 18 / 7 / 3
Week Total / 47 / 108 / 39 / 12
Figure 2.2Main House Toilet Usage by Type and Purpose of Use
#1 / #2
Composting / Flush / Composting / Flush
Day 1 / 4 / 21 / 4 / 1
Day 2 / 1 / 27 / 7 / 1
Day 3 / 0 / 10 / 4 / 1
Day 4 / 1 / 9 / 6 / 2
Day 5 / 3 / 18 / 4 / 2
Week Total / 9 / 85 / 25 / 7
Figure 2.3Total Toilet Usage by Type and Purpose of Use
#1 / #2
Composting / Flush / Composting / Flush
Day 1 / 17 / 37 / 11 / 2
Day 2 / 13 / 45 / 19 / 2
Day 3 / 9 / 45 / 11 / 5
Day 4 / 8 / 30 / 12 / 5
Day 5 / 9 / 36 / 11 / 5
Week Total / 56 / 193 / 64 / 19
iii. Type and Time of Day Tables
Figure 3.1Jeannie’s House Toilet Usage by Type and Time of DayDay / Night
Composting / Flush / Composting / Flush
Day 1 / 20 / 15 / 0 / 2
Day 2 / 24 / 16 / 0 / 3
Day 3 / 16 / 21 / 0 / 18
Day 4 / 12 / 16 / 1 / 8
Day 5 / 13 / 11 / 0 / 10
Week Total / 85 / 79 / 1 / 41
Figure 3.2Main House Toilet Usage by Type and Time of Day
Day / Night
Composting / Flush / Composting / Flush
Day 1 / 6 / 15 / 2 / 7
Day 2 / 8 / 21 / 0 / 7
Day 3 / 4 / 6 / 0 / 5
Day 4 / 6 / 5 / 1 / 6
Day 5 / 6 / 13 / 1 / 7
Week Total / 30 / 60 / 4 / 32
Figure 3.3Total Toilet Usage by Type and Time of Day
Day / Night
Composting / Flush / Composting / Flush
Day 1 / 26 / 30 / 2 / 9
Day 2 / 32 / 37 / 0 / 10
Day 3 / 20 / 27 / 0 / 23
Day 4 / 18 / 21 / 2 / 14
Day 5 / 19 / 24 / 1 / 17
Week Total / 115 / 139 / 5 / 73
iv. Flushes Table
Figure 4Total Flush Toilet Uses and Flushes by Purpose of Use#1 / #2
Uses / Flushes / Uses / Flushes
Day 1 / 37 / 0 / 2 / 1
Day 2 / 45 / 6 / 2 / 1
Day 3 / 45 / 5 / 5 / 5
Day 4 / 30 / 7 / 5 / 3
Day 5 / 36 / 8 / 5 / 5
Week Total / 193 / 26 / 19 / 15
Estimated water usage from flush toilets: 65.6 gallons
26 + 15 = 41 total flushes for the week
1.6 gallons used with each flush
41 flushes x 1.6 gallons of water per flush = 65.6 gallons of water used for the week
Estimated water usage from composting toilets: 0
Note: This estimate does not include the stored rainwater used each day to wash out the bucket used at the Main House composting toilet. Also note, neither of these estimates includes the amount of water used for hand-washing.
GRAPHS
i. Comprehensive Graphs
ii. Type and Purpose of Use Graphs
iii. Type and Time of Day Graphs
vi. Flush Graphs
Discussion
The purpose of the onsite study was to better understand how and why composting toilets are used at Rancho Mastatal.
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In the interview with Tim, I learned that the center uses composting toilets for multiple reasons. The major benefits are threefold:
- water conservation
- fertilizer production
- reduced pressure on the septic tank
The composting toilets conserve water because they do not use water. Whereas a regular flush toilet flushes away 1.6 gallons of potable water with each flush, a composting toilet does not use water to remove the waste. In the bucket system, Tim uses collected rainwater to rinse out the bucket each day, but he does not consider that minimal water usage to be detrimental to the environment, since that water is non-potable.
Tim also estimates that the three composting toilets onsite (including the one not examined in this study) together yield approximately 100 nylon sacks full of humus each year. This humus is used as a nutrient-rich soil additive on ornamentals and other non-edible plants on the property. When the center has an excess of fertilizer, they donate it to the community, where there is always a need for soil fertilizers.
The composting toilets are also useful because they reduce the pressure on the one septic tank for the property. When the septic tank fills, the people at Rancho Mastatal will have to build a new one. While properly-managed septic systems can be fairly neutral to the environment, the workers at Rancho Mastatal would prefer to prolong the life of the current one and not have to build another one for as long as possible.
In addition to these three main reasons for using composting toilets at Rancho Mastatal, Tim also notes that the toilets make a great learning tool. Through their use, Tim and Robin are able to educate visitors about the benefits of recycling humanure.
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Whereas the interview aimed to understand why composting toilets are in use at Rancho Mastatal, the Toilet Use Tally sought to grasp why and how often the toilets are used on a day-to-day basis by a visiting group like ours. In particular, the onsite study looked at the location of the toilet, the type of toilet, the purpose of use, the time of day of use, and the amount that the flush toilets were flushed over a five-day segment of our stay.
It is important here to say a word of caution before proceeding with an analysis of the collected data. While this data may provide some insight into how the composting toilets are used and perceived by groups visiting Mastatal, it is crucial to note that this study was very limited. It studied only one group consisting of twelve visitors plus any other volunteers or workers who happened to be present during the study. The results here may be somewhat indicative of how and why this particular group used the composting toilets, but it would be unwise to assume that these findings are necessarily true for other groups or even for every member in the studied group.