Project manager at ICI, Gareth Clayton said: “Storm-water management continues to be a significant issue across the island which has been worsened by recent increased intensity rainfall.”
He said: “Development on Rarotonga has occurred organically over previous years with limited planning. This has meant that infrastructure and particularly the storm-water drainage networks, both private and public, are in some instances unsuitable for increased concentrations of surface run-off.
“The development of sensitive areas particularly of wetland areas, secondary flow paths and flood plains, or their modification is causing interruptions to existing flows through catchments, as well as environmental problems such as erosion and resulting sedimentation.
“Blockages or diversions of existing public and private storm-water systems are also leading to flooding of low-lying areas, this coupled with increases in rainfall intensity and on-going poor land development practices is a significant concern and impact on storm-water networks.”
Clayton added: “ICI has been promoting awareness of the importance of managing storm water and advocating for more carefully managed development.”
He said a project in process is the drafting of sediment and erosion control standards for land development, which will assist in addressing erosion and resulting effects on infrastructure and the environment.
In addition, as part of a storm-water management feasibility study, the planning of a detailed design for the Muri and Aroko catchments is in the works.
Clayton said they will focus on replacing and improving existing critical public drainage structures across the island to improve capacity.
He said the current priority areas for storm-water management include Muri, Aroko, Turoa, the Back road in Nikao, Rutaki, Avatiu, and Tupapa.”