The stormwater swales in Pegasus have been designed to treat, attenuate and infiltrate stormwater runoff from the roads and residential properties.
The swales have been consented by Environment Canterbury (reference: CRC 135310). To comply with the consent conditions, the soil mix used in the stormwater swales have been selected to achieve the required infiltration rate and the shape or profile of the stormwater swales has been designed to achieve the required attenuation volume.
Additionally the grass cover in the swales needs to be maintained to prevent erosion of the soils in the swale. The infilling of the invert of a swale with topsoil will reduce the capacity of the swale and reduce the infiltration rate through the base of the swale. Consequently, the swale will no longer comply with the conditions of the resource consent. It is therefore important that the soils and shape of the swales are maintained as constructed.
While this system is currently (2014) under the control of Todd Property Pegasus Town Limited, the Council’s Stormwater Bylaw which controls the discharge of water into the stormwater system and the Council’s Solid Waste Bylaw covers illegal dumping of waste in public land still apply.
Council has prepared the attached advice for landowners on the existing stormwater swales in Pegasus. For any further information please contact the Council’s Drainage Asset Manager, Owen Davies on (03) 311 8900.
Yours sincerely
Kalley Simpson
3 Waters Manager
