Our Dual Flush Toilet

We have been planning to take steps to reduce our water consumption, but not making a lot of real progress.   We have been thinking about how to do rain water catchment, grey water recycling, and making landscape changes to reduce water needs.  These projects are fairly large ones, and will have to wait for next summer just out of weather considerations. 


When we saw a daul flush toilet at Costco (of all places), we thought that this seemed like something we could do in an hour or two right now.    So we bought it.   It is a WaterRidge (WR) dual flush toilet with a 1.6 gallon big flush (same as our old toilet), and a 1 gallon small flush.  It cost $200.  I did some searching for Internet material on WR, but was not able to find much of anything.  It appears to be well


Update November 2010:

All 4 of the toilets we replaced with the WaterRidge dual flush units are working fine. 
I noticed that last time we were at Costco the price on the WaterRidge units was down to $60 -- amazing!

We find the flush performance on these units to be very good and essentially never need to use the "high" flush setting.



The installation took a bit over an hour, and was straightforward. 


The critical distances to allow the toilet to fit in the space vacated by the old toilet were all the same, and the same type of wax seal used on the old toilet worked. 


The basic steps are:

  1. Turn off the stop faucet at the toilet

  2. Flush the toilet to drain most of the water

  3. Disconnect the supply hose from the toilet (throw away the old hose)

  4. Remove the toilet by removing the two bolts that hold the toilet base to the floor

  5. Carry the old toilet out being careful not to spill the remaining water

  6. Turn the new toilet over and fit the new wax seal to it.

  7. Put the new toilet in place using body weight to compress the wax seal

  8. Reinstall the bolts that hold the toilet to the floor

  9. Install the new water supply hose and tighten

  10. Turn on the water and check for leaks

  11. Recycle the old toilet

The toilet even came with a good installation manual.



The toilet (so far) has worked flawlessly. 


We replaced the toilet that gets the most use, and since its now a water conserving toilet, we try to use it in preference to the others -- it probably accounts for 90% of all flushes.


The dual flush toilets offer two flush sizes.  In the case of this toilet, its a 1.6 gallon for the big flush and 1 gallon for the small flush.  This is controlled by pressing one of two buttons on the top of the toilet.  The idea is that whenever the situation matches the small flush, you save a half gallon of water over a conventional toilet.


We find that the "small" flush is OK for just about any situation, including solid "stuff".   So, we basically just use the small flush, and we save about 0.5 gallons per flush compared to the old 1.6 gallon flush toilet.   You can still use the "when its yellow ... " rule to save more water.


Without making an actual count, I think we are saving about 10 gallons of water a day -- 3500 gallons a year.  Not earth shaking, but a step.

Update: We are on a well, but for those who pay for city water, the rates vary, but somewhere in the 0.5 to 1 cent per gallons seems common.  If a family saves 5000 gallons a year with a low flush toilet, then a $60 Costco toilet would pay for itself in 1 to 2 years -- so, in addition to making sense for the planet, it makes sense econoically.


We gave the old toilet to the Habitat store.


One wonders why these dual flush or high efficiency toilets are not being used in all new construction?


I think its interesting to note that while the big box hardware stores are doing a lot of advertising about all their products to help you "go green", we could not find a single high efficiency or dual flush toilet in Bozeman.




  Note: As of November 8, 2008, the local Lowes now carries at
least 3 models of low flush toilet -- all under a big "Water Sense" logo.
They are all 1.28 gallon flush, and the lowest price one is only $128.

So, maybe toilet water saving is starting to catch on?



Gary Nov 5, 2007, November 8, 2008, Nov 2010