8. Integrated drainage planning: drainage from roads
In many situations the best results in terms of drainage and the prevention of diffuse pollution will require the co-operation of all the parties involved, including source control in the curtilage of private property within the development. In these cases developers should use their best endeavours to include appropriate source control measures and be prepared to consider representations to this effect made by Scottish Water or SEPA. There is now a substantial body of evidence available to local authorities, who have a key role as the planning authorities, of the desirability of such source control and of pre-treatment within curtilages.
If a coherent approach to SUDS is applied, Scottish Water may make agreements with individual local authorities. Many developments will involve roads which will be built by or adopted by local authorities. The Executive recognises the desirability of SUDS features, such as permeable paving, for roads in residential areas. Where there is reason to consider that there may be a significant amount of diffuse pollution from a road, it should be standard practice for a "pre-treatment" feature, such as a swale or source control filter drain, or combination of features, to be constructed. In normal situations provision should be made for the drainage from roads to join that from other parts of the development, for which SW will be responsible, thus avoiding a "3-pipe" drainage solution. Scottish Water and the roads authority should be expected to make agreements under section 7 of the Sewerage (Scotland) Act 1968 to make the most cost-effective arrangements for drainage from the site.
The Scottish Executive notes concerns that the implementation of integrated drainage has not progressed as quickly as it should have. The reasons may include:
- Leadership/responsibility
- The challenges of collaboration and partnership working
- Stakeholder engagement
- Guidance/information issues
The Executive recommends that all parties take these issues into consideration and hopes that resolving them will provide opportunities to develop plans and effective solutions to tackle water quality and drainage issues. Improved planning may involve:
- Publicising current and developing programmes
- Identify what needs to be done.
- Establish ways in which these actions may be put into practice.
QUESTION 6. Are you content that there should be agreements between Scottish Water and local authorities on road drainage? Are there any reasons why or circumstances in which the parties should not enter into agreements of the type prescribed in section 7 of the Sewerage (Scotland) Act 1968?
At the conference on Sustainability inRoadsDrainage Systems, held in Edinburgh in November 2006, there was a strong welcome for the use of SUDS techniques in road construction, for instance with the M74 and other trunk roads. But for the smaller road and street networks, it was clear that more detailed guidance was needed. The Society of Chief Officers for Transportation in Scotland ( SCOTS) proposes to review the issues with a view to the development of guidance for roads authorities (i.e. the local councils rather than Transport Scotland which has responsibility for trunk roads and motorways).
QUESTION 7.Do you consider that there is a need to prepare guidance specifically for local authorities on the use of SUDS in relation to roads?