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4  FM quick reads on Plumbing

1. Prison Plumbing Retrofit Captures Savings

Every retrofit project has its own quirks and challenges because no two institutional or commercial facilities are the same, after all. But an update of the plumbing system at the Main Adult Detention Facility in Santa Rosa, Calif., presented an array of challenges — not the least of which was its 700 or so inmates — that many maintenance and engineering managers are glad they do not face.

Despite this array of challenges, Sonoma County in 2009 undertook a retrofit designed to curtail the county's overall water use by installing plumbing controls on the facility's sinks and toilets in order to minimize inmate abuse of plumbing fixtures.

In addition to its imprisoned population, the 30-year-old detention facility features a challenge that most facilities do not — a sink and toilet in each room. Each fixture presents an opportunity for an inmate to cause problems for managers and technicians.

"Typically, in the detention environment, you tend to have a lot of things flushed down the toilet that shouldn't be going down there," says Steve Bartlett, maintenance program manager for Sonoma County, referring to such items as sheets, clothing, and contraband. "From a maintenance standpoint, we had to put bolts in a lot of the drain plumbing to catch things. We thought that in addition to water savings, (the retrofit) would help us control what was going down the drains."

Bartlett says he has been more than pleased with the results of the retrofit. A June 2006 meter reading showed that the facility had been using 116 gallons per person per day.

"As we moved through the project, the numbers start coming down," he says, adding that current readings show the savings are around 16.8 million gallons per year. "As of 4/30/2014, the inmate population was around 710, and the meter reading was 50 gallons per day. It has gotten as low as the low 40s.

"It's astounding because that's water that doesn't have to be pulled out of the aquifers, it doesn't have to get pumped, and it doesn't go down the sewer lines. Out of all of our energy-saving methods, this was probably the most successful one. We ended up doing (the same retrofit) to our juvenile hall, as well, after this project."

2.  Water Audit: Create a Fixture Inventory

A water auditor should create a fixture inventory and add to this list information on fixture units from the International Plumbing Code. The fixture unit table lists hot, cold, total and drainage fixture units for most available fixtures.

The goal of the audit is to determine total water use, so the auditor can use the table showing total fixture units without concern for individual hot and cold fixtures. For waste fixtures, the auditor can use the table showing drainage fixture units. A fixture's flow rating will determine the fixture unit category to use from the table — e.g. flush valves vs. flush tanks on water closets.

Items such as wall hydrants do not have associated fixture units, due to their sporadic use. When reporting fixtures other than traditional units, such as sinks, their purpose can determine their flow rate. For instance, the specification for a commercial ice machine generally will list an associated flow rate.

Once the auditor compiles the list, the total fixture units represent the facility's total water use. The code has two additional tables for converting fixture units to flow rates, in gallons per minute. The two tables provide rates for facilities that predominantly feature flush-valve water closets, or toilets, or for facilities that predominantly use flush-tank water closets.

The conversion tables provide for diversity of use. A low number of fixture units corresponds to a nearly direct conversion to flow, whereas a higher number of fixture units generates an expected diversity with a lower corresponding flow rate. For waste, on average, most of the water supplied eventually becomes waste for the fixtures. Other items, such as irrigation, might not return supply to waste.

3.  Saving Water, Streamlining Maintenance

Recent generations of plumbing fixtures and components feature technology designed to reduce water use, extend performance life, and minimize system maintenance.

Maintenance and engineering managers looking to specify products that address water-use issues have several strategies to consider to stay abreast of important technology advances related to plumbing products that meet their organizations' need to minimize water use, and improve life-cycle costs:

  • Low-flow, aerator-equipped faucets are designed to reduce water use. Urinal and toilet flush valves also are designed for low-flow operation. Adjustable-flow showerheads also offer a method of lowering water use.
  • Water filters can extend piping and fixture life by removing many of the minerals that cause corrosion and leaks and shorten product life, as well as eliminate the fouling that causes buildup in the pipe and fitting walls and, in turn, reduces capacity.
  • No-chemical ultraviolet water treatment products eliminate the use and handling of hazardous chemicals while lowering costs. Technicians need to change the bulbs in these units annually.
  • Water chillers and drinking-water coolers are designed to use 134A CFC-free refrigerant, and all leaded parts have been removed. The piping is soldered with lead-free silver solder.
  • Barrier-free fixtures are available in new designs to ensure compliance with ADA requirements for access. Operating pressures on the fixtures are at or below 5 pounds. Hands-free operation and dual level fixtures for sinks, drinking fountains, toilets and showers eliminate barriers to access.
  • Water-softening products reduce scale and enable water heaters, washers, fountains and other fittings and piping to continue operating properly over a longer useful life, while reducing consumption of soap and other cleaning products.
  • New fixture-surface coatings provide longer, more trouble-free operation, even on brass fittings.
  • Flow-rate and totalizer submetering enable technicians to compare water use by zone in buildings, by building, or by area in a building. Submetering highlights high-use areas and reduction opportunities where plumbing products require upgrades. It also provides information to identify leaks and peaks as managers compare use from one month to another and prioritize replacement plans.

4.  Saving from Vigilance on Water Conservation

Vigilance is the best defense against wasted water in restroom plumbing systems. The sooner technicians can identify the source, the quicker they can prevent water waste. Regular, preventive inspections are the surest way to spot and correct problems.

The first and least costly method to eliminate waste is to look for leaks and high flow rates and, where detected, to replace leaking fixtures, faucet aerators, shower heads, and toilet valves with the newer products that use less water. Replacing high-flow restrictors with low-flow restrictors can reduce water consumption at each faucet by 50 percent.

Another waste reducer is submetering, which measures the flows in various areas and can help managers determine which buildings or systems are the biggest users and wasters. One quick way to determine the presence of leaks is to read the meter at two-hour intervals when no water is being used. The difference between the two is water wasted from leaks. With this comparison, managers can focus conservation efforts and resources on projects and produce the largest paybacks.

Submetering savings can result from previously unidentified leaks that reveal themselves in an unusually high flow volume in a metered area. Once technicians measure baseline flow, they can take periodic readings and compare them to the baseline.

Technicians also can compare similar areas between buildings. If two areas in different buildings have about the same number of fixtures and usage, their flow rates should be similar.

Some buildings also collect, treat and recycle sink water as grey water for use in toilets. This strategy can substantially reduce potable water use and flow into the sewer. The sewer flow is charged automatically based on the water supplied.


Plumbing , plumbing retrofit , water conservation , green

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