Legislative Assembly for the ACT: 2002 Week 4 Hansard (11 April) . . Page.. 1136..
(Question Nos 97 and 98)
Mrs Dunne asked the Minister for Urban Services and the Minister for Planning, upon notice:
In relation to common trenching.
(1) Is common trenching an accepted practice in jurisdictions other than the ACT.
(2) How long have discussions been underway between land managers, utilities and land developers on this issue.
(3) What are the impediments to agreement.
(4) Do the Ministers anticipate a resolution of the impediments.
Mr Wood: The answer to the member's questions is as follows:
(1) Common trenching is an accepted practice in other jurisdictions. There are five Joint Trenching Agreements in place between electricity and gas suppliers throughout New South Wales. It is also common practice in the ACT. Telstra lines and gas have been sharing trenches in the ACT since 1989. In 1996, following successful trial installations, the Joint Trenching Agreement was expanded to also include electricity cables.
(2) Discussions have been underway between land managers, utilities and land developers for at least 13 years in the ACT. Implementation of the three way trench on a trial basis took place about six years ago with progressive adoption since that time.
A new Joint Trench Agreement is currently being negotiated by the service authorities to include Transact Communications services.
(3) At present common trenching is restricted to telephone, gas and electricity with provision now also being made for additional broadband communication cables. Sewer and stormwater are constrained by gravity. Water is constrained by lack of flexibility in pipes and is also considered a hazard to other services in the event of a burst. It is also not considered safe to have electricity and water in close proximity in the event of leaks from either service. It is also not feasible to use in some areas where there is rock just below the surface which prevents trenches from reaching the required depth.
(4) The Government is ensuring that all new Land Developments include a requirement in their Deeds of Agreement that Joint Trenching be adopted wherever practical.