DCAN 14: Siting and Design of Radio Telecommunication Equipment
Sharing Existing Sites, Masts and Other Infrastructure
3.20 The conditions in code system operators’ licences require them to explore the possibility of sharing existing sites and masts. Evidence of this should accompany planning applications. Mast sharing will often enable quicker and cheaper installation. However, it may not be the optimum solution in all cases. Masts that accommodate several systems can, in certain cases look quite cluttered and ungainly resulting in increased visual intrusion. Other constraints on mast sharing include;
- Coverage Problems – The existing mast may be poorly located or not have sufficient height to give the required coverage. This could result in additional sites being required.
- Radio Interference – Antennas need a set amount of vertical separation, usually a minimum of 1 metre, although a separation of 0.5 metres can sometimes be achieved between apparatus belonging to one operator. The degree of separation is an important matter in assessing the visual impact of a shared mast.
- Structural Loading – Existing masts may need to be replaced or strengthened with a bigger structure with a consequent effect on visual amenity. In this situation a decision will have to be made whether the increase in size is preferable to an additional site.
- Third Party Property Rights – In some instances the lease agreement with the site owner may not allow for sharing or for the extension of the compound. Where extra space is required to accommodate either a larger mast and/ or additional apparatus such as radio equipment housing, the site owner must be willing to enter into an agreement with the operator in order that the proposal can progress.
3.21 Operators are advised to explore the various ways of overcoming these constraints before submitting a planning application. If this has not been done the Department will normally seek further information.
3.22 In any instance where there is a dispute regarding the sharing of an existing mast or site, either party may ask the Director General of Telecommunications to resolve the matter. If the Director General considers it appropriate, he may direct the relevant telecommunications operators to share. The powers available under the Regulations do not, however, cover the refusal by a third party, such as a landowner to allow shared use of a mast.
3.23 In assessing proposals for a new mast the Department may wish to discuss with operators whether certain locations have the potential for future mast sharing, and if so be satisfied that it can accommodate additional equipment.
3.24 An alternative to mast sharing may be site sharing. This involves a new installation being located in close proximity to an existing one. One mast of good design may go relatively unnoticed but a number of masts could draw the eye and provide a prominent focus. Site sharing will appear more visually acceptable if the masts and other base station elements - equipment housing, power supply, access tracks and fencing - appear as a single group.
3.25 When deciding whether the dispersal of masts is preferable to site sharing, operators need to consider the area’s character. Landscape and visual assessment techniques may be needed to help to decide which approach minimises the landscape and visual impact.