UW Water Recapture

Executive Summary:

Our project is aimed at wastewater capture and reuse, from the reverse osmosis (R/O) unit in the BB-Wing of the medical sciences building. Through a series of storage tanks and pumps this wastewater will have a second use in the cooling tower located in the same room. Our project will reduce total water consumed in the building by repurposing a waste product as a usable resource.

In the larger picture this project represents a rather modest savings, however, reducing consumption of water lessens the impact on our overall water infrastructure and can be considered an adaptation strategy should the predicted impacts of climate change occur, including but not limited to reduced snow pack and water availability in the Pacific Northwest.

We are requesting $10,521 for this project. We predict this investment could be recouped in as little as 4-8 years. Based on measurements over the last two years this project may save between $1,250-$2,500 per year at the current water rate of $15 per hundred cubic feet (ccf). We hope this project can be a model for potential future projects in buildings with a similar setup. However, due to the structure of the University budgeting system we were not able to propose a loan or attempt to roll the savings into additional projects.

We have been working with Dennis Garberg, maintenance supervisor for the Health Sciences building zone, along with John Leaden, a retired facilities employee, and Michael Flanagan, Analyst for Finance and Business Services at Facilities Services. 

Student Involvement:

In fall 2010, a team of multidisciplinary undergraduate students, led by Alex Chin, discovered this project opportunity while participating in the Environmental Innovation Practicum and took action for further development. The students worked closely with those in the Facilities and Alterations Department who were familiar with the conceived project and the respective units. John Leaden, who has 20+ years working in the Facilities Maintenance Department, provided support for developing a feasible plan along with his strong knowledge and experience with the operations of the two mechanical units of concern.

Since the inception of the project Alex has graduated and passed the project along to Duncan. Duncan was able to retain Nick Wang from the previous group and continue to move the project forward.

All of the volunteering will be nearly completed with a grant from CSF. Due to the nature of the project all of the work must be performed by UW personnel. However, to date there have been many hundreds of person-hours dedicated to this project. These hours were not cataloged directly but they have included touring the facilities, crafting a budget and work plan, and helping to specify the appropriate equipment with the help of facilities services.

The only remaining pieces are to view the finished product and to execute our communication plan. 

Education & Outreach:

If awarded a grant from the CSF to fund our project we would work with various communication channels throughout the University to educate the student body about our project, the role the CSF played in helping this project come to life, and the impact of our project. This includes the UW Daily as well as a couple of departmental newsletters. We would also be happy to provide images and a story for the CSF facebook page or ESS communications.

One of our main educational goals is to shed some light on the inner workings of the UW and show how students are able to have a positive impact. Second we hope that by effectively communicating our project to the student body and educating them about the CSF that more projects will be proposed to the CSF. As the former chair I wish to see the CSF continue to be successful but I also want students to know that not every project has to be a green wall for everyone to see, which is one of the inherent challenges of our project. Because it is in the bowels of the University we will have to work with facilities to get access for pictures to help communicate our story.

Unfortunately, we the students, will not be around beyond this year so ongoing communication of our project at future events such as the Sustainability Summit will not be possible by us. However, as a number of work units at the UW attend these events it may be possible for them to carry on communication of this project into the future. 

Environmental Impact:
  • Water
Project Longevity:

Environmental Problem:

Water is a precious resource, even in the rainy Pacific Northwest, and all of the water that flows through our pipes is potable. This means that every drop used in toilets, sinks, drinking fountains, cooling towers, and reverse osmosis units has been treated to drinking water quality. This treatment process requires vast amounts of energy, and money to maintain the infrastructure and deliver the water. Any waste places an additional burden on these systems but also reduces the amount of water available for any number of purposes.

The University of Washington has taken great steps to reduce water consumption throughout campus by installing low-flow toilets, sinks, and showers. But there are other areas where excessive water is used and consequently wasted. Our project has identified and seeks to resolve one of these problems.

Currently, the Reverse Osmosis (R/O) unit in the BB tower of Magnuson Health Sciences building consumes approximately 300,000 gallons of potable water, annually, to provide the facility’s various purified water needs. However, at optimal conditions only 75-80% of the incoming potable water is usable. Each year approximately 90,000 gallons is discarded as wastewater, also known as reject water. Reject water is clean for industrial purposes but is not fit for human consumption.

In addition to this waste, the buildings cooling tower, which is in the same room as the R/O unit, consumes nearly 100,000 gallons of potable water each year. As a result our project expects to mitigate the consumption of nearly 90,000 gallons of potable water each year. This is enough water to provide for the drinking water needs for nearly 500 people for a whole year, every year.

Explain how the impacts will be measured:

Currently, water consumption and waste at both the R/O unit and the cooling tower are measured with mechanical meters that are periodically checked by facilities staff. As part of the measurement of impact of our project, facilities services has agreed to install a meter between the storage tank and the cooling tower. Additionally, a solenoid valve will be fitted to the water lines so that the water available in the storage tank is used before any additional city water is used for the cooling tower. This setup does two things:

  1. Ensures available R/O reject water is used first
  2. Allows direct measurement of the total number of gallons of R/O reject water used

With the meter on the R/O reject water line and a meter on the line from the storage tank to the cooling tower we will be able to calculate the percent of R/O reject water consumed by the cooling tower, a measure of system efficiency, as well as total gallons saved, a measure of system effectiveness.

Based on observed meter data we know there is wide variability in both R/O reject water production and cooling tower water consumption. We do know that the cooling tower consumes more water than the R/O unit produces over a given time period. For all but 3 days over the last two years the cooling tower has consumed more water than the R/O unit has produced. In addition we will have over 300 gallons of storage capacity. So we expect our system efficiency to be very high and to mitigate almost all of the 90,000 gallons currently being wasted. 

Total amount requested from the CSF: $10,521
This funding request is a: Grant
If this is a loan, what is the estimated payback period?:


ItemCost/ItemQuantityTotal Cost
Equipment & Construction
275 gallon water storage tank$750.00 1$750.00
30 gallon water collection tank$350.00 1$350.00
Pump$250.00 1$250.00
Pump w/ Direct Drive$250.00 1$250.00
Misc. materials (Plumbing)$750.00 1$750.00
Misc. materials (Controls)$500.00 1$500.00
Publicity & Communications
Plumbers$100.00 24$2,400.00
Sheet Metal shop$100.00 10$1,000.00
Electricians$100.00 16$1,600.00
Refrigeration specialists$100.00 4$400.00
Overrun costs$100.00 20$2,000.00
General Supplies & Other

Non-CSF Sources:

Project Completion Total: $10,521


TaskTimeframeEstimated Completion Date
Order Materials3 weeks2/8/2013
Plumbing1 week2/15/2013
Sheet metal1 week2/22/2013
Electric Work1 week3/1/2013
Refrigeration1 week3/8/2013
Buffer time2 weeks3/22/2013
Project Complete3/22/2013

Project Approval Forms: