A rainwater system for the Construction Materials Laboratory in More Hall

Executive Summary:

The Construction Materials Laboratory (CML: http://www.ce.washington.edu/research/construction/facilities.html) at More Hall is an instruction laboratory where undergraduate students of the department of Civil and Environmental Engineering (CEE) and the College of Built Environments (CBE) study different construction materials and gain hands-on experience with mixing portland cement concrete. In order to achieve the desired strength and durability of the concrete, the concrete structures are cured in a fog room adjacent to the CML. Curing is a process of providing adequate moisture, temperature, and time to allow the concrete to achieve the desired strength and durability.  The fog room produces ultra-fine water droplets in the air that is closely monitored by a programmable system that controls the humidity and temperature setting.   Currently, the prescribed relative humidity condition in the fog room is ensured by continuously sprinkling potable water to the room via two sprinkler heads with an average rate of 1200 gallons/day. By proposing to install a rainwater collection and purification system in and adjacent to the laboratory space, we seek to provide CML with a supplementary, sustainable source of water for fog room use. This will result in reducing the laboratory’s tap water consumption by an average of 600 gallons/day. The quantifiable economic benefit equals $1,800.00 per year in water consumption.  In addition to the economic benefits, the proposed project will serve as a campus wide educational tool and give University of Washington students, faculty and staff the possibility to learn more about innovative use of sustainable water management practices.

We are seeking a grant of 32,000 USD for construction materials, installation work and operational expenses.

Student Involvement:

The CML rainwater collection & purification system will be designed, operated and maintained by student teams from Civil and Environmental Engineering department and from the College of Built Environments. The student teams will consist of undergraduate students and at least one project manager will be chosen amongst the department’s graduate students. The student involvement in different phases of the project is described below:



The system design* will be implemented as a Capstone project in the Spring 2015. The project group or groups of 5 students will be responsible for:

-          Estimating the monthly rainfall on More Hall roof & sizing the rainwater cistern.

-          Designing & sizing the water distribution system (gutters, pipes, pumps, sprinklers etc.) under the direction of a CEE professor and by following the Environmental Health and Safety (EHS) requirements of the University of Washington

-          Choosing suitable construction materials

-          Creating a schedule for the construction process

-          Designing a sampling and maintenance plan for the system by following the Environmental Health and Safety (EHS) requirements of the University of Washington


* A similar rainwater system has been explored at another K-12 institution and the proposers have been involved in the project by assisting the institution with the project management, design and installation of the system.  The effort is still on-going and is scheduled to be installed in February of 2015.




The system operation will be automated. However, continuous involvement of a few student volunteers (3-4 per quarter) will be required throughout the lifetime of the project in order to monitor the system operation and the water quality.

In order to ensure that adequate water quality is maintained throughout the project period, water samples will be collected on a weekly basis from the exit of the rooftop cistern and at the point of use within the CEE Concrete Lab. All samples will be collected in acid-washed, pre-baked (400 °C), 60-mL amber, borosilicate glass bottles and subsequently monitored for a suite of chemical and microbiological parameters, including pH, alkalinity, dissolved organic carbon (DOC), total nitrogen (TN), various metals (including Cu, Pb, and Fe), turbidity, fecal coliforms, and total coliforms. pH will be determined by means of a Thermo-Scientific Orion 5-Star multiparameter meter, alkalinity, DOC, and TN by means of a Shimadzu TOC-VCSH analyzer, metals by means of a PerkinElmer ELAN-DRCe ICP/MS system, turbidity by means of a Hach 2100 series turbiditimeter, and fecal and total coliforms by plating on appropriate selective media in accord with Standard Methods.1 Samples will be analyzed within one week of collection, and stored at 4 °C prior to analysis.

(1) APHA Standard Methods for the Examination of Water and Wastewater; 22 ed.; APHA, AWWA, WPCF: Washington, 2012.


CEE faculty and graduate students will supervise the student volunteers whose tasks will be defined in the sampling and maintenance plan.  CEE faculties, Mike Dodd and Amy Kim, previously met with officials from the Department of Health that have been involved with the Bullitt Center and the Perkins School in developing and permitting their rainwater catchment system.  The water quality information that will be gained from this study will be valuable for both the Department of Health and for the research community as not much has been published in this area.




Student volunteers (3-4 per quarter) and their graduate student supervisors are mainly responsible for conducting maintenance activities. These activities include but are not limited to:


-          Emptying and cleaning the rainwater cistern every summer

-          Changing the UV filter of the rainwater treatment unit

-          Cleaning & replacing other components of the rainwater treatment unit


The consultancy and help of facilities services staff will be needed with all maintenance activities involving plumbing. However, these activities are not expected to be frequent and thus we are not expecting them to cause any significant increases in facilities staff members’ workload.

Education & Outreach:


Civil and Environmental Engineering department offers education in six different fields of engineering: construction, structural, transportation, geotechnical, environmental and hydrological engineering. During their junior year, undergraduate students are required to take one course on each topic and choose a major for their senior year. Although all fields of civil engineering are strongly connected to each other, CEE seniors rarely get a chance to gain hands-on experience on projects that would combine these different fields. The design and operation of the CML rainwater collection and purification system would provide CEE students, faculty and staff with an extraordinary opportunity to gain experience on sustainable water management practices and interdisciplinary teamwork. As one of the main goals of the study is to increase interdisciplinary collaboration within different fields of study, student volunteers from other departments would also be strongly encouraged.  Potential integration is with the Center for Urban Horticulture in designing a rain garden outside the CML.

The installation and operation of the CML rainwater system would not only offer opportunities for interdisciplinary project work but also for interdisciplinary research. In the supervision of CEE faculty members, the student volunteers and graduate student project managers could monitor and analyze the operation of the system by tracking changes in the quality of the purified rainwater over time and investigate the effects of different water sources on the concrete curing process in the fog room. The results of these studies could be presented in conferences and other professional events, and published in scientific journals.


One of the goals of CML rainwater project is to serve as an educational tool and provide UW community, and anyone outside of UW interested in rainwater harvesting, with information about sustainable water management practices. All operation results (water quality and flow, required maintenance activities etc.) and a detailed description of the design & installation process of the CML rainwater system will be available to public on the project website. The project will be promoted in UW media (The Daily at the University of Washington, University of Washington Conservation magazine, UW today newsletter, The Bridge Newsletter of CEE department) and in environmentally focused local information channels (Facebook, LinkedIn, neighborhood newspapers etc.). Project group could also collaborate with King County Department of Permitting and Environmental Review and help with department’s endeavors on collecting information about the operation of rainwater systems in Seattle area by providing operation data from the CML rainwater system. Moreover, groups and individuals who are interested in learning more about the project set-up and operation are offered a possibility to schedule a site tour.

Environmental Impact:
  • Water
Project Longevity:

We are expecting our project to have an approximate lifetime of 10 years. Our budget proposal includes project operation and maintenance costs for the next 5 years. For continuous operation, we would need to apply for additional funding after 5 years of operation. However, the proposed system is flexible in that individual components of the system can be easily decommissioned if needed. We can also explore the idea of reconstructing the project after 5-10 years for a more efficient way of saving potable water in the Construction Materials Laboratory.. As for the next 5 years, the student involvement throughout the project lifetime is ensured by continuous volunteer recruiting and project promotion within the CEE department.

Environmental Problem:

Construction Materials Laboratory (CML) at More Hall is an instruction laboratory where undergraduate students of CEE and CBE departments learn about different construction materials and gain hands-on experience in mixing Portland cement concrete. In order to allow the concrete to achieve the desired properties for its intended use, the concrete structures are cured in a fog room in adequate moisture and temperature conditions. Currently, the 100% moisture conditions in the fog room are ensured by continuously sprinkling potable water to the room with an average rate of 1200 gallons/day.

By proposing the installation of a rainwater collection and purification system in and adjacent to the laboratory space, we seek to provide CML with an additional, sustainable source of water for fog room use, and a way to reduce laboratory’s tap water consumption by approximately 600 gallons/day. The rainwater system would consist of an outside cistern, two pumps, a water treatment system with UV filter, a storage tank for purified water and a sprinkler system for the fog room and have an estimated cost of 32,000 USD. The economic benefit of the system over its estimated lifetime of 10 years would be about 16,000 USD.

Explain how the impacts will be measured:

The impacts of the CML water system will be measured by metering water flow both in the potable water sprinkler system and in the rainwater sprinkler system. The metering results will be posted to the project website on the weekly basis and the student volunteers will analyze the changes in the average daily water consumption over time. Moreover, in order to monitor the operation of the rainwater treatment unit, the quality of the rainwater will be analyzed by sampling before and after treatment. The sampling results will be available for public on the project website.

Total amount requested from the CSF: $32,000
This funding request is a: Grant
If this is a loan, what is the estimated payback period?:


ItemCost per ItemQuantityTotal Cost
Rainwater cistern12,000112,000
Water distribution system (pipes,connectors,sprinklers)2,00012,000
Water treatment system with UV2,00012,000
Rainwater pump50021,000
Water flow meter50021,000
Water sampling expenses4,00014,000
Plumbing and installation work10,000110,000

Non-CSF Sources:

Project Completion Total: $32,000


TaskTimeframeEstimated Completion Date
Set up the project team 1 month4.30.2015
Develop design1 month4.30.2015
Finalize the design and produce construction documents1 month5.31.2015
Produce an Operation & Maintenance plan1 month5.31.2015
Submit and obtain required permit(s)2 month7.31.2015
Purchase construction materials2 month9.30.2015
Install and construct rainwater catchment system2 month9.30.2015
Plumbing & installation work2 month10.31.2015
Operate project5 years minimum10.31.2020