Environmental compliance and specialist design services – Redmunds Spur Subdivision, Cashmere, Christchurch

 

Description: Redmund Spur Subdivision is marketed as an exclusive new hillside community, above Cashmere Road on the lower slopes of the Port Hills. The first three stages have been completed and released to market. e2Environmental has managed the environmental compliance for the first 60 lots of the subdivision as well providing specialist design input on 3 waters infrastructure.

 

Our expertise: Using stormwater modelling packages, e2Environmental analysed catchment runoff potential. The entire site drains to a central gully where conveyance control was required to resist erosion during normal and flood conditions. We detailed energy dissipation solutions, including riprap armouring, and sized culverts and structures to safely convey runoff and meet consenting requirements. Sustainably sourcing rocks onsite for the channel provided positive cost benefits for the developer and lowered the carbon foot print for the development.

 

Through an active role in liaising with Christchurch City Council and the affected parties, a future connection downstream to the city’s Stormwater Management Area was established.

 

e2Environmental’s oversight of erosion and sediment controls led to minimal silt discharge from the site during construction. This involved utilising local knowledge to; liaise with ECan, provide general input on construction methodology, and assist with floc selection.

 

Outcome: Over the course of two construction seasons, no abatement notices were recorded nor were there any significant silt discharges to the wider network. Following successful completion of the first 3 stages, further stages will commence in the near future when the city council’s downstream stormwater and wastewater infrastructure capacity increases.

As a result of e2Environmental’s involvement with this development e2Environmental is currently working with Environment Canterbury and CCC to prepare best practise guidelines for erosion and sediment control on Port Hills Loess. This remains as an ongoing related project.

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