News

Water leak repair case study report – Citroen, Newport.

Author: Graham Mann, Water Audit Expert.

We attended site on 22^nd July 2013, to carry out a repair on a leaking water supply pipe at the Citroen site in Newport.

Previous leak detection carried out on 10^th July 2013 had raised a point of interest when gas was inserted into the water supply. We believed this area to be the area of the water leak location. The area was subsequently marked ready for excavation and repair.

Upon arrival at site, we excavated the area that had been previously marked which revealed a 42mm plastic coated copper supply.

A small area of this pipe was wrapped in Denso tape. Denso tape is a tape which is non-hardening and non-cracking. It is highly resistant to mineral acids, alkalis, salts and micro-organisms and highly impermeable to water, water vapour and gases. Denso tape is mainly used for the protection of buried or exposed pipes.

We removed the Denso tape which revealed a soldered joint in the pipe work with a pin hole in it. (Please see Picture 1)

The pipe was thoroughly cleaned and fitted with a repair clamp. The water supply was restored to enable us to test the repair. As the repair had been successful, we wrapped the pipe in fresh Denso tape. We checked the water meter and this was now stationary indicating that all leakage on site had been repaired. The meter read as at 23^rd July 2013 was 18761m³.

Upon arrival at site to carry out leak detection the site had a flow rate of approximately 9 litres per minute and an average daily usage of 12.96m³ per day. This equates to a usage of 4730m³ per annum and an annual cost of £12,487.

This rise in consumption is a difference of 5.6m³ per day which equates to a usage of 2044m³ per annum and an annual cost of £5,396.  As a result of the repair, an annual saving has been achieved of £5,396.

 The excavation area was then backfilled and fully re-instated and the area left clean and tidy.

Recommendations

We will submit a leak allowance and liaise with the water supplier on your behalf to secure a leakage refund for the water lost to ground during leakage.

Picture 1 – The leaking supply pipe                                                                                                                                                                                                                                                                                                                                                                                    Picture 2 – The repaired supply pipe