Case Studies

Skip to page navigation

Apartment & Condominiums

Cedar Park Apartments

  • 75 Units (97 toilets)
  • Reduced water use by 34%
  • Northshore Utility District
  • Replaced mixture of 3.5 & 1.6gpf toilets with Premium WaterSense 1.0 gpf toilets

“Not only are we getting a lot of good positive feedback from our tenants, we also have to do less maintenance, vis-à-vis clogged toilets, etc. The water savings are very substantial and any multifamily property would benefit from it and would help keep our environment healthier”.

– Mohammad & Arash A. – Property Managers

Campus View Apartments II

  • 27 units
  • Reduced water use by 38%
  • Seattle Public Utilities
  • Replaced 34 1.6 gpf toilets with Premium 0.8 gpf models

“These new .8 gpf toilets are unbelievable. Not only do we save 30 to 40% on our water bills, but maintenance from inoperable toilets and clogs was almost eliminated. Any

property owner with inefficient toilets who doesn’t jump on this program while it lasts will definitely be sorry.”

– Nate A – Property Manager


The Experience Music Project

The Experience Music Project (EMP) has installed an innovative water treatment system for its cooling tower. This system utilizes a water softener regularly recharged with table salt (NaCl), rather than chemical scale and corrosion inhibitors and biocides. This video features Lee Richardson, Facilities Manager for the EMP, talking about his experience with the new water treatment system over the past year. This footage was taken as part of a panel discussion at the Saving Water Partnership Cool Tunes Seminar on water efficient cooling towers hosted at the EMP on December 8, 2010.

View video: EMP Cooling Tower Experience (4 minutes)

Seattle Municipal Tower Hybrid Cooling Tower

In 2008, the Seattle Municipal Tower installed one of the first new generation hybrid wet/dry cooling towers in the country. These innovative cooling towers can operate with or without water (or half-dry and half-wet), depending on load and temperature conditions, with the potential for significant water savings. In this video, Mark Nieman of McKinstry Co., explains why this type of cooling tower was chosen, what the pos and cons have been, and how this new technology has continued to evolve over time. This footage was taken as part of a panel discussion at the Saving Water Partnership Cool Tunes Seminar on water efficient cooling towers hosted at the EMP on December 8, 2010.

View video: Hybrid Cooling Towers – Seattle Municipal Tower (12 minutes)

More information on cooling tower efficiency

Cool Tunes Manual (pdf) is a tool developed by Seattle Public Utilities to assist engineers and building management staff in increasing their cooling tower efficiency – including reducing water and energy use and the amount of treatment chemicals needed.

Flush Valve Toilets

Landmark Buildings

High-efficiency fixtures are the new water conserving standard for restroom fixtures, and include high efficiency toilets (HETs) with 1.28 gallons per flush (gpf) or less, and high-efficiency urinals (HEUs) which use one-half gallon or less. This video highlights the substantial savings a number of landmark Seattle buildings have achieved through installation of these fixtures.

View video: High-Efficiency Restroom Fixtures (1 min 34 sec)

Bank of America 5th Ave Plaza

The Bank of America 5th Avenue Plaza building retrofitted all of their bathrooms over a two year period . This has resulted in a high performance bathroom for all building occupants and visitors. These actions have contributed to the building achieving LEED- Existing Buildings Gold certification.

  • High-efficiency toilets installed – 236
  • WaterSense urinals installed – 74
  • New aerators installed 1.0 gpm – 250

Utility Savings: $114,424 per year

Fred Hutchinson Cancer Research Center

Background: Many large medical or highly-specialized facilities have a need for purified water, which can produced by a variety of methods such as deionization, distillation, or reverse osmosis (RO), which uses membrane filtration technology to produce water of a selected pureness.

Challenge: Increase water efficiency of RO production.

System Parameters: 6,000 gallons per day RO system consumption, 3,000 of which was production water and 3,000 was reject water going to waste.

Results: For every gallon of produced RO deionized water, reject water was reduced from 1 gallon to 0.5 gallon. This resulted in a savings of 1,500 gallons per day, the equivalent of 2 CCF on a water utility billing basis.

Cost & Savings: Current water and sewer cost is a combined annual average of $15.09/CCF. Savings from the efficiency improvement is $30 per day. Carried out over a 260 day/year time frame, total annual savings to Fred Hutchinson CRC is $7,847. The cost to implement this efficiency improvement was $300. This represents the cost of a system adjustment and testing administered by the maintenance contract technician. The simple payback was less than two weeks.

Additional highlights: Besides the RO operational improvements, the FHCRC has reduced total water use by one-third since the year 2000 while more than doubling the total building square footage over the same period.

This impressive conservation success story has been achieved through reduction of trap cooling water for sterilizers, installation of efficient restroom fixtures, installation of water softening water treatment for cooling towers, and innovative water reuse systems for water captured from a variety of sources.

Jim Walker, Chief Facility Engineer for the FHCRC takes us on a video tour (9 min) to see firsthand how the different parts of their water reuse systems work.

The Pink Door

The Pink Door is a restaurant icon located in the Pike Place Market vicinity. Like Toscana Pizzaria, The Pink Door had a water-cooled refrigeration condenser unit that served a walk-in cooler, and also had a water-cooled ice machine. Because The Pink Door is a full service restaurant, determining water use specifically for the refrigeration unit required metering prior to replacement.

  • Details: One water-cooled walk-in cooler and one water-cooled ice machine replaced with air-cooled units
  • Project Cost: $10,000
  • Utility Savings: $7,804 per year

Seattle Schools

The Seattle School District has been using the available kitchen equipment rebates for a number of years to replace food steamers, dishwashers, ice machines, and a host of other types of kitchen equipment that doesn’t consume water, but qualifies for energy utility rebates. When combined the result of using high efficiency Energy Star rated equipment is significant.

Toscana Pizzeria


New air-cooled refrigeration system replacing a single-pass water-cooled system.

Existing conditions

Project site is a small Capitol Hill restaurant specializing in pizza. Existing refrigeration system provides refrigeration for a small walk-in cooler.

  • Pre-project daily average water consumption was 1,698 gallons per day on an annual basis for the business.
  • It was estimated that 36% (615 gallons) of the total water consumption by the business was from the water-cooled refrigeration system, with a much higher use in the summer season.
  • The utility cost savings estimate was $3,900 per year.


  • A new remote condenser was located on a patio in the back of the restaurant.
  • Labor and materials for the project was just under $8,000.
  • Project completed May 2010.


  • Water consumption for three years post project completion averaged 1,223 gallons per day, a reduction of 29%.
  • If one two-month billing period in the summer of 2011 was not considered (the consumption was abnormally high) the resulting savings would have been much closer to the original estimate.
  • Approximately 30% water consumption reduction.
  • Estimated water and sewer utility cost savings is $3,500/year.
  • This project achieved a simple payback of one year when the 50% of project cost SPU utility rebate is considered.

University of Washington

The University of Washington (UW) has managed to reduce its water consumption by almost 40% over the last 10 years. This equates to a savings of around 800,000 gallons per day. This remarkable savings achievement has been the result of many water conservation projects, including equipment and leak repairs, installation of water conserving trap cooling kits on steam sterilizers, replacement of older toilets, urinals and showers with new efficient models, and upgrades or replacement of water cooled equipment, including refrigeration equipment and vacuum producers.

Dave Fields, chair of the UW Conservation Project Development Team, and John Leaden, Special Projects Coordinator, take us on a tour to see firsthand some examples of the water conservation projects they have undertaken.

View video: Water Conservation at the University of Washington  (8 min)

W Hotel

The W Hotel in downtown Seattle made the decision to install a laundry reclaim system from AquaRecycle. What made this system unique, and so compelling to the customer, was the inclusion of steam condensate reclaim in addition to the regular laundry water reclaim. The W Hotel, with 426 guestrooms, had an abundance of steam condensate from domestic hot water production, steam dryers, and other laundry uses. Collecting this pure hot water and eliminating the use of fresh potable water for condensate tempering gave this project added benefits over a straight reclaim system. The net water savings actually exceeded the pre-project use of water.

  • Details: Laundry water reclaim system included one 2,000 gallon collection tank, three levels of filtration and treatment, and control system monitoring temperature and storage level control.
  • Project Cost: $153,800
  • Utility Savings: $70,443

About Laundry Water Reclaim Systems

Large commercial laundries, whether contained within a single hotel or a stand-alone facility serving multiple clients, can nearly all benefit from the use of a water reclaim system. Reclaiming up to 80% of the water used in washing clothes save the laundry operator significant cost by reducing both water and sewer utility bills, and energy bills from the heating of that water. The unfortunate aspects of laundry reclaim systems are that they require extra maintenance of laundry equipment, add a level of complexity in terms of the chemical formulas, and often times are not well understood by day to day operators of laundry equipment. If these modest complications can be addressed initially and built into the normal expectations of operation, the benefits will more than compensate for the additional steps needed for long term performance.