Soil erosion is a natural process where gravity, wind and water wear away the soil surface. This process can be accelerated by activities like quarrying, earthworks construction and subdividing land. Find out how you can reduce your impact.
Read the the most recent issue of Sitelines, our newsletter for earthworks contractors.
Sitelines: stable sites, healthy environment
Winter is over, and spring is finally here!
As we all know, it has been a very wet autumn and winter so here’s hoping the rain can ease off and the ground can start to dry out.
Our Land Development team are very much aware of how much the weather has delayed construction and are here to assist you. However, please be aware as the 1 October earthworks season approaches, that you have all the consents you require to commence works, that your pre-construction documentation is submitted and approved, and that you are contacting your monitoring officer to advise of works commencing to set up the monitoring.
The annual workshops were again run over July and August this year. All days were fully subscribed and it was good to see the differing industries attending these workshops. Although the weather did was not always good on these days, it was really impressive to see flocculant working so effectively.
A huge tank you to the sponsors of these workshops, Erosion Control Limited and Cirtex Industries, who without their financial support would significantly increase the costs of these workshops, and also to the City Edge Alliance construction the Hamilton Section of the Waikato Expressway for allowing us to use their site for the onsite visits.
The annual breakfast and erosion and sediment control awards were again held on Friday 1 September 2017.
This year the winners of each category were:
Small sites - Joint winners Mangahoanga Stream Culvert - Seay Earthmovers and Longswamp Stream Diversion –Downer New Zealand Limited
Medium sites - Te Rapa Gateway - Schick Civil Construction
Best Environmental Outcome - Hamilton Section of the Waikato Expressway Mangaonua Stream Bank Training Works- City Edge Alliance
Innovation – Sliding Valve- Fulton Hogan Limited
Large Site – Fulton Hogan/HEB Joint Venture – Huntly Section of the Waikato Expressway
The stand out winner this year is the environment as standards onsite continue to improve and innovations to make erosion and sediment control more efficient and effective continue.
The photo shows this year's winners at the breakfast ceremony. (R-L: Winners at this year's breakfast ceremony: R-L Stephanie Kirk (Cityedge Alliance), Sarah Bland, Jason Haggerty, Wayne Viall (Fulton Hogan/HEB JV), Iain Fletcher (Downer), Josh Wilkinson (Fulton Hogan), Bevan MacLachlan (Seay Earthmovers), Rob McCraig (Schick) and Councillor Stuart Kneebone)
As some of you will be aware, this wet weather has seen an increase in pumping/de-watering of sites which at times has overwhelmed control devices and ended in a sediment discharge occurring. The Cityedge alliance has come up with a new “Permit to Pump” initiative that has significantly reduced all pumping issues onsite, and is a quick and easy process for all involved.
The issue also arises onsite when there is a requirement to stop a control device from discharging via the outlet, but the pulleys have jammed, or are too water logged to lift. Fulton Hogan have come up with a new initiative to install a slide in the outlet pipe.
Just a reminder, if you are using flocculant and floc sheds/floc boxes, please ensure that all records of chemical usage is accurate and up to date. It is a requirement to submit these to WRC if requested.
A request and enquiries portal is now available on our website. When you fill in a web form you will receive a reference number for your request and confirmation that it has been received. Our team will work on your request and get back to you within two working days.
Click here to access the portal and send us a web form.
Each year in the Waikato region, large areas of land are stripped of vegetation or laid bare because of construction or operating of quarries, subdivisions, roads, cleanfills and other developments. Without appropriate erosion and sediment control, these activities can result in accelerated on-site erosion and greatly increased sedimentation of waterways, lakes, estuaries and harbours.
Various studies show earthworks sites may produce 10 to 100 times more sediment yield compared with pastoral land, and 1000 times more compared with permanent forest cover.
Sediment can damage our waterways’ ecology by:
These damaging effects often totally change instream communities. Recovery from the impacts of sediment deposition is slow - years rather than months.
As well as ecological changes, sedimentation may:
A resource consent may be required from the Waikato Regional Council if your activity will involve soil disturbance near streams, lakes, wetlands or coastal waters, or where the works are on steep land.
Consents also may be required for stormwater discharges from these sites. Soil disturbance, roading, tracking or vegetation clearance projects that don’t require consents are called ‘permitted activities’, and these require compliance with specific conditions.
Find out more about resource consents (including application forms), or call the Resource Use Freephone on 0800 800 402.
For technical support and access to the spreadsheet to assist in ensuring that sediment retention ponds and culverts are sized correctly, please refer to this webpage www.mcconnellconsultancy.co.nz(external link).
You can download ‘Erosion and Sediment Control – Guidelines for Soil Disturbing Activities’ via the above link.
Please note the following sections are no longer relevant, and you will need instead to refer to the corresponding fact sheets:
Small site sediment control
Silt sock / filter log [PDF, 164 KB] - Now includes additional controls
Sediment Control Brochure(external link) - Hamilton City Council
Almost every site will require an erosion and sediment control plan (ESCP).
The guideline below will help you prepare your ESCP. Use these guidelines when planning your earthworks project to develop an erosion and sediment control plan, and to prepare your project’s resource consent application if one is required. Note that granted resource consents will most likely require compliance with these guidelines. The guidelines should be used as best practice on permitted activity sites as well.
Most resource consents will require works to stop between 30 April and 30 September, unless written approval is obtained from the Waikato Regional Council.
This guideline is to assist you with making your application to continue works through the winter works shut down period.
Most resource consents will require a pre-construction meeting with relevant parties involved in the project.
The checklist below will assist you with topics to discuss and agree upon with the Waikato Regional Council representative prior to commencement of works.
Pre-construction checklist [PDF, 439 KB] - You can edit directly into this PDF (you might need to check or update your software to do this - you'll need Acrobat Reader(external link)). Make sure you save it out to your desktop before you start editing, if you start editing in the original version on this webpage, your changes won't save.
Most resource consents will require ESCs to have as-builts undertaken, and to be certified that they have been constructed in accordance with the approved ESCP or Waikato Regional Council's erosion and sediment control guidelines.
These sheets are to assist you with the information required for the as built certifications.
Download the sheets below:
The Waikato Regional Council offers workshop training opportunities for the earthworks industry.
A one-day workshop with a practical focus on constructing erosion and sediment controls. This workshop covers best practice erosion and sediment control methods in accordance with the Waikato Regional Council's Erosion and Sediment Control Guidelines, Waikato Regional Plan requirements and legal obligations under the Resource Management Act 1991 (RMA). This workshop also includes a visit to a working site to view controls in the field.
A one-day advanced workshop with a practical focus for preparing erosion and sediment control plans and tips to assist with preparing land use resource consent applications. This workshop will cover the Waikato Regional Plan's rules relating to soil disturbance activities, and will include practical exercises in preparing an erosion and sediment control plan and site risk analysis.
Prerequisite to this workshop: Participants must have previously attended the practical erosion and sediment control workshop or the previous two-day planning erosion and sediment control workshop.
Peter Stevens - PS Environmental Services Ltd
Peter has 14 years’ experience in erosion and sediment control and resource consents. Since establishing his company in 2006, Peter has worked with a range of clients including regional councils, developers and contractors. Construction projects he’s worked on include subdivisions, state highways, roads, tracks, cleanfills, forestry conversions, hydro-electric power schemes, wind farms, bridges, stream diversions and quarries.
Peter has extensive experience in erosion and sediment control plans, resource consent applications and compliance monitoring, and provides erosion and sediment control training and advice for organisations both in the private and public sectors.