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Progress with the iron mains replacement programme 2010 - 2011

1. Under the Pipelines Safety Regulations 1996, regulation 13A, HSE approved iron mains replacement programmes for the year 1 April 2010 to 31 March 2011 for the gas Distribution Network Operators (DNOs) shown in Table 1. The progress in meeting the national and individual network targets is also shown.

2. Normally HSE approves iron mains replacement targets annually. However, HSE will approve programmes lasting more than one year if:

3. In Table 1 the targets marked with an asterisk (*) form part of 3-year approved programmes from 1 April 2010 to 31 March 2013.

4. In 2010 -11 nationally 3621.6 km of iron mains were decommissioned against the approved target of 3720.4  km – a shortfall of 98.8 km.

Table 1 - Mains replacement performance 2010 - 2011 by Distribution Network

Network Network operator Decommissioning Target (km) Decommissioning Actual (km)
North West National Grid Gas plc 538 1849 482 1776
East of England 605 604
West Midlands 344 316
North London 362 374
North of England Northern Gas Networks Limited 528.1 531.8
Scotland Scotland Gas Networks plc 270.0* 271.7
South of England Southern Gas Networks plc 712.3* 687.2
Wales & West Wales & West Utilities Limited 361.0* 354.9
All networks 3720.4 3621.6

5. The winter of 2010 – 11 included a spell of extended severe weather and the iron mains decommissioning work undertaken by each of the DNOs was affected by this and this is the reason given for the shortfall. Some areas of the country were more severely affected by the cold weather than others. However, in all cases, the DNOs reduced or halted their iron mains decommissioning work and diverted resources and personnel to the repair of the very high number of gas escapes that occurred during the cold weather.

6. Each DNO should, so far as is practicable, comply with a programme approved by HSE under Regulation 13A. However, if due to matters outside of the DNO’s control they are unable to comply with their approved programme then, were they to be prosecuted for non-compliance, it would be a defence for them to show that they had complied with the programme ‘so far as is practicable’. An extended spell of severe weather provides for such a defence.

7. HSE has taken the decision not to take enforcement action against those DNOs who have failed to comply with their approved programmes in 2010  -  11 as a result of the severe weather in that period.

8. As part of its monitoring strategy and 5 year intervention plans for the Distribution Network Operators (DNOs), HSE continues to carry out mains replacement audits to check that mains are decommissioned in accordance with the policies and procedures in the DNOs’ Gas Safety (Management) Regulations 1996 safety cases.