Revised Study Design

Revised Study Design:

Rain Water System for the New Environmental Science and Engineering Building

Re-submitted March 6th

Table of Contents

  • Introduction
  • Evaluating Rain Water System Sustainability
  • Purpose and Goals of the Rain Water Study
  • System Boundaries
  • Criteria
  • Data Collection Update
  • Key Contact People
  • References
  • Appendix A: Systems Design
  • Appendix B: Study Flow Chart


    It is impossible to turn back the clocks and live the way our ancestors did thousands of years ago, but changes in our current lifestyles and the way in which we view the natural world can help us to achieve a more sustainable environment. Sustainable development can be both a conceptual framework and a goal for maintaining and achieving sustainability. The Bruntland Commission has provided the necessary objective for sustainable development, "to meet the needs of the present without compromising the ability of future generations to meet their needs," but this is only the goal of sustainable development, it is not a solution nor is it a framework from which to build a sustainable environment.

    Fresh water is one of our most important natural resources as it is necessary for survival and lacks a substitute. We depend on water for survival as well as for our convenience; we drink it, cook with it, wash with it, travel on it, and an enormous amount is used for the purposes of agriculture, manufacturing, mining, energy production, and waste disposal (Environment 264). Therefore, with respect to sustainability, maintaining the quality and quantity of water is a top priority.

    Water covers approximately three-fourths of the earth's surface, creating many problems for water management and the implementation of water conservation technologies (Environment 264). However, from a community level many water saving tactics can be implemented to conserve this most precious natural resource.

    In light of the new building, the future Centre for Environmental Science and Engineering (ESE building), scheduled to open in 1998, has provided an opportunity for a WATGreen team to initiate the study of a rain water system for the building. The results of this study could lead to the incorporation of a rain water system into the plumbing of the ESE building.

    The proposed rain water system would involve using rainfall that would otherwise be collected as surface runoff and channeled through the Region of Waterloo's storm water sewer system eventually leading to the Grand River and other small tributaries. With a rain water system, 'free' rainwater would instead be stored in a rain water storage or retention tank and then used for flushing toilets, which does not necessitate the use of clean chemically treated water. The practice of a rain water system on the University of Waterloo campus, especially in the design and construction of the new ESE building, not only promotes water conservation, but it also promotes an aspect of sustainable development of such an irreplaceable resource.

    In turn, it is the task and determination of the WATGreen team to examine the likelihood of a rain water system for the ESE building. Considering a significant component of sustainability is related to economic concerns, not only will a bio-technical and it and study be completed, but a socio-economic study will accompany it as well. Prior to the performance of any such studies however, it is necessary to first identify the components of the rain water system itself. The WATGreen team has made it their goal to identify components of the rain water system that are only the most "environmentally" efficient. That is, each of the components identified will use as little energy, water as is possible, while minimizing costs and waste generation.

    The physical components of the new building's rain water system will consist of: the retention tank used for rainwater storage, the plumbing system which will channel the water to the toilets and channel contaminated water to sanitary sewers, a connection to the sanitary sewer system to remove the waste or sewage from the system, a storm sewer connection in case of overflow in the retention tank due to excessive precipitation, and 6 litre toilets or the smallest possible flush toilet available on the market to reduce the amount of water expended by flush toilets.

    The inputs into the system will depend on the climate and seasonal conditions in the Waterloo area. Rainfall will be the prime input into the system, however some energy will be required to operate the pump, which will pump the water from the retention tank to the toilets.

    After all of this has been completed, what will it all mean to the University of Waterloo? Simply, the inclusion of a rain water system in new developments on campus will promote development which is sustainable, and if the system is incorporated into the design of the building, the University of Waterloo may be regarded as an environmental pillar of the community. In other words, UW would be setting the standards for future developments, not only on campus, but for the Kitchener-Waterloo community and beyond.
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    Evaluating Rain Water System Sustainability

    In order to study this system, it becomes necessary for the WATGreen team to determine what approach or perspective will guide them through the system study. It is necessary to adopt a specific approach so as to focus the study and avoid being sidetracked. Similarly, in adopting an approach early on in the study, direction is established within the study and wasted time on unnecessary information is avoided.

    A rain water system is a means of water conservation and involves the implementation of a unique plumbing system thus, the study will be completed from a conservationist/technical perspective. The conservationist's perspective works toward achieving the optimal use out of existing resources, while attempting to minimize the use of additional inputs into the system. The technical aspect of the perspective aims at designing a technically feasible plumbing system that incorporates the conservationist framework outlined above. These approaches set the framework from which sustainability will be evaluated because in order for the development of the new building and the plumbing system in particular to occur, integration of a natural resource (water), and integration of human technologies will have to be implemented in a sustainable manner.

    The sustainability framework will be based on both a financial study and an ecological savings study. The financial study will determine the predicted monetary savings to the University of Waterloo for treated water consumption versus the implementation of a rain water system. The ecological savings study will be determined by the rain water system infrastructure and the amount of rain water used instead of chemically treated water. Also, the amount of contaminated water channeled to the Region of Waterloo's sewage treatment plant will also be assessed.

    As analysts of the possibility for a rain water system within the new building, it becomes necessary for the WATGreen team to know to whom the issue is of concern and who has some stake in the development of such a system. Actor systems are comprised of both the main persons or stakeholders in an issue and the social rules and power structure in which they operate. These are the people who are affected directly or indirectly by a problem and who may have a vested interest in its outcome. Actor systems can include core actors who are at the centre of an issue, supporting actors who are less involved but can exert influence over an issue, and should-be actors who may be affected by a problem or its solutions but are unable to participate in problem resolution or who are unaware of the issue (University of Waterloo).

    Within the realm of this system study, it is vital to consider the roles of the members of the community that will be affected in any decisions or developments. The inclusion of these actors will allow the development of the new building to be accepted by the community. For example, we feel the listed actors below will, or should be involved in the development of the plumbing system of the ESE building. Their stake in the matter is described in detail following their listing below:

    The roles of these actors is critical to the study of the system. For example, the role of the students is to assess the feasibility of a rain water system in the ESE building. The plant operations staff are responsible for the technical aspects and the maintenance of the system, and the New Building Committee will be responsible for the implementation of a rain water system into the cost and design of the building, as are the architects and contractors.

    The supporting actors should influence the core actors to implement a rain water system. Weigle Reality should encourage the University of Waterloo to implement a rain water system into the ESE building because of the success they have in their condominium complex, which has a rain water system incorporated into its design. The Region of Waterloo should encourage the core actors to incorporate any environmental technologies into new developments to sustain the Waterloo community.

    The should-be actors are mainly the financial sponsors of the new ESE building. For example, private donors and the provincial government who are mainly providing the funds for the building should have a say in the design of the building and it's environmental standard. The students and WPIRG should be concerned about what the University of Waterloo is constructing on campus and in light of the attention the natural environment is receiving in the 1990s the students and WPIRG should make sure that the UW only promotes the most environmental technologies available.
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    Purpose and Goals

    The roles of humans within this issue has been already discussed. It is ironic that this WATGreen team of 1995 are faced with a task of redesigning a system which will replace a plumbing system that was designed by humans and accepted for so many years. Directing rain water to a storm sewer may have seemed like a solution to the causes of excessive overland flow as a result of human developments. Because humans have created many impermeable surfaces into the natural system, humans have also had to create a system to redirect the surface runoff or overland flow. Therefore, in trying to rectify the problem environmental engineers have devised a system to remove rain water from roof tops and other concrete and asphalt surfaces.

    However, in trying to remedy the problem of overland flow, rainwater has needlessly been redirected to rivers and other water bodies. To a certain degree this water is necessary to replenish the hydrological cycle, but some of the rainwater can be redirected for use in buildings that would otherwise require chemically treated water. Therefore, the purpose and goals of this study is to:

    1. Determine the amount of water needed to flush toilets in a building the size of the ESE building.
    2. Determine the amount of rainwater that could be accumulated on an annual basis.
    3. Evaluate possible storage methods for the rainwater (ie. the size of the retention or storage tanks).
    4. Examine a suitable plumbing system with the inclusion of 6 litre toilets or the lowest possible flush toilets available on the market.
    5. Determine the present costs for supplying chemically treated water for flushing toilets.
    6. Determine initial costs of implementing a rain water system in the new building and the long term financial savings.

    In order to implement the purposes and goals above, it is necessary to understand the classification of the components of the system. The socio-economic classification of the rain water system includes the physical components of the system as well as the financial costs of the system. These physical components include: structure costs (retention tank), plumbing, construction and installation costs, sewage treatment costs, and long term maintenance of the system. The bio-technical or inputs into the system include: the hydrological cycle, the rain water system, and the sewage water system.
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    Rainwater System Components and Boundaries

    While studying the inputs and outputs of the system, it is extremely necessary to focus on the system's boundaries so as to avoid the unnecessary inclusion of irrelevant or inapplicable data. The dimensions of the new ESE building will be approximately 148 000 square feet, which will be approximately the size of the present psychology building located on the Waterloo campus. The size of this new building is relevant in determining the potential amounts of rainwater that could be accumulated from the collection surfaces. The larger the building, the more collection surfaces that could be located. The environment of the system is enclosed within the structure of the building, allowing inputs from the physical environment. The environment includes the collection of rainwater from the roof of the building and all balconies or patios, and the plumbing which will include the most efficient toilets suitable for non-residential use, and the retention tank or sistern. The size of the sistern which will supply the water needed by the flushing of toilets, will be a function of the flushing demand of the new building as well as the amount of rainfall per year.

    The system is dependent on the initial inputs into the system (rainwater). However, in order to have a reliable system it is necessary to have a backup source in order to provide for maximum efficiency in the event that sufficient amounts of rainwater to meet the flushing demands does not fall. Therefore, a connection to treated water supplied from the Region of Waterloo, which will also provide water for any other plumbing component in the building such as sinks, will fuel the system when needed. The main feature of this system is to reduce the stress on water use on the University of Waterloo campus and the system will benefit the environment by producing less stress on the sanitary sewer system and eliminating waste more efficiently.
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    Criteria To Be Used to Evaluate the Feasibility and Benefits of a Rain Water System

    The first criteria used to evaluate the system will be the precipitation levels which occurred in previous years, and recorded at the University of Waterloo. The second criteria will be the flushing demands of toilets in the environmental science and engineering buildings. The last four criteria will be used to formulate a Cost-Benefit Analysis. Theses four criteria will be:
    1. energy requirements to operate the pump
    2. the costs of water necessitated by present flushing demands
    3. the costs for the over all implementation of the rain water system
    4. the cost for maintaining a rain water system over the long-term

    In order to evaluate the feasibility of the system, the precipitation will be measured and the flushing demands will be monitored. The precipitation data will be obtained from the Larry Lamb ecology lab located on the University of Waterloo campus. This precipitation data is an extremely important aspect of the system as it will indicate whether or not enough rainfall is present in one year to meet the flushing demand. Similarly, it will indicate how much treated water will be needed to compensate for the difference in rain water and flushing demand if it is found that not enough rain falls in one year to meet the flushing needs of the new building. The flushing demands at the University of Waterloo will be measured via counting the average number of flushes in an 8hr. day. The information required to complete a CBA will be obtained from the University of Waterloo's Plant Operations department, from Paul Weigle a contractor and supporter of rain water systems, and from the new building committee.
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    Data Collection process Update

    Flushing Demand Audits

    The flushing demand audits, which involved monitoring washrooms for the amount of flushes per day, are still in progress. Each group member has been designated a specific time and day which is different from the other members of the group. This is to account for the possible variations in flushing that may occur on the average day. All flushing audits are being performed in different washrooms within the Psychology building as it is comparable in size to the planned Environmental Science and Engineering Building. So far, one week of these audits has been completed. Unfortunately it was a rather "slow" flush week as few toilets were flushed during the audit or monitored time period.

    Rainwater System Tour in Kitchener Apartment Complex

    It was brought to the group's attention early on in the study, that a rainwater system similar to the one we are proposing, has already been established within a Kitchener condominium complex. Paul Weigle, the system's designer and contractor is the owner of the complex and agreed to a tour of the rainwater system he presently uses in the building to flush toilets, wash cars and water surrounding vegetation. The tour was extremely useful and interesting as it offered useful answers to many questions that the group had. Mr. Weigle was very informative and as a result, the rainwater system for the new building is looking more and more feasible than this group had originally expected.

    Important information obtained from Mr. Weigle:

    Information Obtained from Plant-Operations

    Before contacting Plant Operations, a list of questions was drawn up. Calling the main switchboard at Plant Operations allowed contact with Rick Zeleganes who is involved with plumbing and water use at the university.

    Our list of questions were supposed to help us determine water usage in various buildings on campus, and allow us to extrapolate some general numbers to figure out the appropriate size of the proposed cistern in the ESE building. The list of questions is as follows:

    Many of these questions were based on the assumption that flush demand tests had been done at the university. Unfortunately, no studies had been done.

    Secondly, Rick Zalagenes provided a spreadsheet of water consumption on campus, which revealed that is was impossible to determine how much water is used per building over a year. We were told that every building was metered in the past, but high maintainence costs prompted Plant Operations to stop this metering and rely on four meters for the majority of the campus. These meters are named:

    The only buildings which are monitored individually are:

    The idea of using Optometry as a model for water use was dismissed to it's low population and water-cooled air conditioning. The former causing low water use levels in the winter, and the latter causing very high consumption rates in the warmer months.

    Due to this lack of information regarding water use in each building, it was also impossible to find out the amount of water used for flushing toilets and urinals. It follows that it is also impossible to determine the water use costs that flushing represented each year.

    Rick Zalagenes contacted Phil Simpson in Plant Operations who was able to answer the rest of questions regarding the number of fixtures and the nature of the fixtures. According to Mr. Simpson, there are 57 toilets and 25 urinals in the psychology building. Plant Operations is in the process of retro-fitting every fixture with "Crane Delaney" flush valves. These particular flush valves use only a small amount of water each flush and can be adjusted to account for water pressure levels and water use levels. (Water pressure in lines tends to be 57 psi, and varies with time of year and water use levels.) The valves are being replaced as the old fixtures break-down. Most of the fixtures have been replaced as of March 1995.

    Crane Delaney flush valves are set to use 2 gallons per flush on toilets and 1 gallon per flush on urinals. These valves are attached to Crane and American Standard porcelain fixtures. Other water-conserving valves being used on campus include "Teck II' which use 1.5 gallons and 0.75 gallon per flush for toilets and urinals respectively.

    Information Still to be Collected

    The group is well on its way but information is still lacking. Flushing audits will continue until March 17,1995. The costs of building the system still have to be established and will be done so after further consultation with Mr. Paul Weigle. ***Similarly, the amount of money that the University of Waterloo presently spends on water to flush toilets is still to be determined.***The group must also design the areas of collection upon which the rainwater will fall and then be channeled to a drain through which the water will flow into the cistern. This information will also affect the size of the cistern. The more collection sites, the more water accumulated necessitating a larger tank.
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    Key Contact People

    Rick Zalagenes - Plant Operations Phil Simpson - Plant Operations Chris Ford - City of Kitchener Paul Weigle - Rain water Contractor and Realtor Dr. John Greenhouse - New Building Committee Chair Larry Lamb - Ecology Lab on the UW campus
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    Berg, Linda., Peter H. Raven and George B. Johnson. Environment. New York: Saunders College Publishing, 1993.

    "Building's Coming, A Home for Earth Sciences", in The UW Gazette, Wednesday, February 15, 1995.

    Phone Interview with Paul Wiegle, Friday Febraury 17, 1995.
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    Appendix A

    Rain Water Systems Diagram

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    Appendix B

    Components of a Rain Water System and Cost-Benefit Analysis

    not ready yet...sorry!
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