Earthworks
Earthworks is a common activity across the Horizons Region. Earthworks are a necessary part of preparing land for residential development, building roads and some stream works. However, the clearance of woody vegetation and earthworks can accelerate erosion. This accelerated erosion has the potential to damage water bodies if sediment from earthworks sites are poorly managed.
Sediment can damage the ecology of waterways by:
Modifying or destroying instream, estuarine and coastal values (such as water quality and habitat); and
Affecting aquatic animals and plants due to smothering, change in food sources and interruptions in lifecycles.
Sedimentation can also damage water pumps, reduce domestic water quality, spoil an area’s appearance and affect the cultural values tangata whenua associate with water. Earthworks can also destabilise sand soils in coastal areas, which can cause unwanted effects associated with wind-blown sand.
We monitor consents at earthworks sites across the Horizons Region, helping to ensure sites are managed correctly in order to minimise the impact on waterways when sediment leaves sites during rain events. A significant part of this job involves checking to make sure sites are being managed in accordance with an approved erosion and sediment control plan, as well as meeting other resource consent requirements.
Resource consent requirements
You may need a consent if your activity will involve soil disturbance near streams, lakes, wetlands, coastal dunes, on steep land or if the area of disturbed land exceeds 2500 square metres per property per 12 month period. Earthworks that do not require resource consent are called ‘permitted activities’, and these require compliance with a set of permitted activity standards and conditions. To determine whether you need a consent or if your activity may be permitted, please call our Consents Team on freephone 0508 800 800 or by emailing them emailing before getting your project underway.
Guidelines and factsheets
While there may be differences between needing a resource consent or being a permitted activity for earthworks, both situations require erosion and sediment control methods to be installed prior to, and maintained, during the earthworks activity. The guidelines (which can be used as best practice for permitted activities) and fact sheets below help design erosion and sediment control devices and an erosion and sediment control plan.
These factsheets can assist contractors and consultants to ensure sediment retention devices are designed and sized correctly. You’ll notice some come from Waikato Regional Council, but the advice is relevant for the Horizons Region.
Some include best-practice updates which improve device performance. We encourage contractors and consultants implement these updates in best practice when preparing and implementing an erosion and sediment control plan.
Winter works application guidelines
Pre-construction meeting checklist
As-builts for control structures
Most earthworks resource consents will require erosion and sediment control structures to have as-builts completed, and to be certified that they have been constructed in accordance with the approved Erosion and Sediment Plan. These sheets are to assist you with the information required for the as-built certifications.