In this study, 275 residential toilets were replaced with 3 models of Ultra-Low-
Flush Toilets (ULFTs). Water savings were measured by: metering the water use per flush of each toilet replaced as
well as each new ULFT; monitoring 15% of the new ULFT's installed with flush counting devices; and,
comparing indoor water use records prior to and after installation of the new ULFT. A follow-up
customer satisfaction survey was also administered.
Customer satisfaction of the new ULFTs was high, with an overall performance rating average of
8.4 out of 10 (10 being excellent). Ninety-six percent of the participants with Caromas said they would
recommend the new ULFT compared to 92% of those with Niagaras and 69% of those with Gerbers.
Caromas rated best in clogging performance, with 96% of the respondents saying they never clogged,
compared to 81% of the Niagaras and only 51% of the Gerbers. When asked about double-flushing,
74% of the respondents said they never had to double-flush Niagaras compared to 70% of Caromas and
53% of Gerbers. Based on the survey results, we found that each household averaged 2.96 persons
and 2.7 toilets.
Before removal of the toilet to be replaced, water use per flush was metered. The average water
use of the replaced toilets was 4.16 (gpf), with a range of 2.1 to 6.7 gpf. Once installed, water use per
flush of the new ULFTs was also metered. The Niagaras averaged 1.69 gpf, the Gerbers 1.8 gpf, and
the Caromas 1.68 gpf for the large volume flush and 0.88 gpf for the small volume flush. Caromas
offered the greatest amount of savings due to the small volume flush feature, and the Niagara offered a
high potential savings due to the absence of a leak-prone flapper valve. The flush counting devices
showed that each new ULFT was flushed an average of 8.9 times per day.
The water savings achieved from this program were found to be two-fold: first, there were water
savings associated with the reduced flush volume and second, water savings were achieved through a
reduction of leaks associated with the older high flush toilets. Almost 75% of the participants with flush
counters had their new ULFT installed during winter months; therefore, the full extent of toilet leaks
cannot be calculated until water use records are obtained after the ULFT is in place for a full winter
period. This data will be available in March 2004.
Based on a preliminary evaluation of the data, a savings of 42 gallons per household per day, (or
15,511 gallons per household per year) was achieved by this program. Therefore, the total water
savings achieved by this program is estimated to be 13.1 acre feet (4,265,525 gallons) per year, or 262
acre feet (85,310,500 gallons) over a 20 year period. This program is cost effective when compared to
the estimated cost of future water development projects currently being planned. Includes 15 references, tables, appendices.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 570 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 19 |
| Published : | 01/11/2004 |
