Occupying buildings after an extended closure

Guidelines for protecting water quality

When buildings are vacant for extended periods and water isn’t being used regularly, the water can become stagnant, degrading water quality over time.

The Consolidated Mutual Water Company (Consolidated) is providing guidelines for businesses on how to clear or flush the water in a building’s internal water system before reoccupation of the building.

The goal is to replace stagnant water in the building’s water system with fresh, high-quality water. Consolidated recommends working with your building’s engineer or facility manager for this process.

You MUST FOLLOW the guidelines below IN ORDER:


Turn on the cold water inside the building (all break room sinks, drinking fountains, utility closets, restrooms, etc.) on each floor.

Start from the furthest point away from where the water enters the building. For example, if a building has five floors, start on the fifth floor and work your way down to the first floor, running cold water only.

The cold water temperature will go from slightly warm to cold once you’ve successfully flushed the cold water system.


Flush hot water storage tanks to displace stagnant/discolored water with fresh water.

For boilers and hot water tanks, flush the tank according to the manufacturer’s flushing instructions.


Repeat step 1 – using only hot water.

The hot water temperature will go from warm to hot once you’ve successfully flushed the hot water system.


Flush and perform preventative maintenance on point-of-use devices or systems, such as cooling towers, systems providing additional water treatment, etc., according to the manufacturer’s recommendations.

You may occupy the building once all domestic water service lines, internal plumbing, and point-of-use devices/systems are flushed and adequately maintained.

See Your Consumption With ‘Eye on Water’

To help save water by using these tips, you can save even more water by signing up for our Eye on Water. Eye on Water allows you to monitor your water consumption on a daily basis, and let you know when you may have a leak.

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Water is a precious resource we need to live and cannot afford to waste. Use water wisely…


Download Water Conservation Tips

For more information about water conservation and tips, please go to http://coloradowaterwise.org.