Case Study - HM PRISON

Water Cost Reduction
Saving: £57,000

Water Cost Reduction at HMP Parkhurst, Isle of White

Working in conjunction with the works department at the prison, the water meter was fitted with a logging device in order to produce a visual daily and over night flow profile.

The results demonstrated a 1.5 litres per second base load, which equated to 47,304 m3 per annum. In money terms this equates to unaccounted water losses of £72,000 per annum. We then carried out a full site survey in order to ascertain the reason for the high consumption. There were two areas:-

There was a water leak on the main four inch water supply to the bottom end of the establishment.
There were uncontrolled flushing urinals. The cost of water from urinals was a staggering £35,000 per annum. We then proceeded to install flow-tec passive infra red urinal flush controls to all urinals that were flushing continuously uncontrolled.

Leakage Detection & Repair

The water leak was visible above ground, near a fire hydrant, and this was repaired internally by prison staff. The flow rate logging device was then re-installed to the main incoming water meter, which demonstrated a substantial reduction in the base load and the savings demonstrated were £42,888 per annum. The capital cost to achieve this saving was less than £8,000, therefore a pay back was less than 3 months.

Laundry Effluent

The sewage charges were based on standard domestic rate with no allowances for non return to sewer for laundry steam generation, evaporation form laundry and green house irrigation.

Action Taken

We applied for a Trade Effluent Consent to Discharge which effectively reduced the sewage charges for laundry effluent by approximately 50%, which realised an annual saving of £15,000 per annum. The capital costs to achieve this result were £750.00. Pay back was almost immediate.

Total Savings Achieved: £57,888.00 per annum