Hydrological Services
Drainage annex for urban building schemes
Drainage Annex for Urban Planning
Drainage annexes to city building plans are designed to provide clear guidance for managing runoff and drainage in accordance with National Outline Plans. These annexes outline strategies for sustainable drainage and water-sensitive urban design.
This integrated approach ensures that new developments are planned with resilience in mind—minimizing flood risks and supporting effective urban water management from the outset.
Runoff water management
In recent years, runoff management has become a key component of urban planning. Effective treatment of runoff at the lot level helps reduce peak flow rates, ease the burden on municipal drainage systems, and promote groundwater recharge by maximizing infiltration. Design strategies focus on delaying runoff, enhancing soil absorption, and directing water back into the aquifer. These efforts not only support flood mitigation but also contribute to sustainable water resource management. As part of the building permit process, both the local authority and the Water Authority require a professional assessment outlining runoff management measures tailored to the specific site and conditions.
Water and sewer annex
The water and sewer annex is a critical component of the planning documents required during the urban building plan approval process. Its primary role is to assess the expected demands and impacts of the proposed development on local water and sewage infrastructure.
This annex includes:
The annex must align with existing master plans for water supply and sewerage in the project area. If such master plans are unavailable, the planner is responsible for surveying the current infrastructure and providing informed recommendations for necessary upgrades or modifications.