Good weather days means good news for the project team and our contractors.

This issue provides more detail on the Stage 2 finishing works and the Stage 3 investigations, both of which are happening now.

We also have an important reminder about when to apply for a Bylaw Authority for those who have had the SOS work completed (Stage One and Two), and to let us know how you’d like to receive cut and carry notifications.

A quick recap on why this work is happening

Stopbanks are only as strong as their weakest link and are vulnerable to damage.

Over the years non-approved structures, trees and gardens have been established on public land. This can create weakness in the stopbank, which can cause water to flow through and lead to the stopbank failing.

This work involves removing some of the vegetation and structures to enable the repair and strengthening of the stopbank.

Stage Two: What’s happening?

To recap, Stage 2 is 95% complete with finishing work being done now in conjunction with Stage 3 works. There are two parts: Removal of the tree stumps next to the Rowing Club, and tidying and maintenance around the concrete floodwall along Henderson Street.

Earlier this month, the stumps were removed. This involved tracing their roots back to the size of a thumb, extracting them from the area, and then rebuilding the stopbank. This image shows the work in progress, where the stumps have been removed and the compacting work to repair the stopbank has begun. The work has been completed since these photos were taken.

The floodwall tidy up will be complete in the next few weeks.

Stage Three: Geotechnical work – Why are we doing this?

Unlike the previous stages, we have limited geotechnical data on file for us to access. This is why we are doing thorough testing in the area. This testing includes hand augers at every second property, and boreholes and Core Penetration Tests (CPT) around the start and end of the Stage 3 section.

A CPT is used to determine the properties of soils. This is done by pushing a steel cone (about 32mm wide) into the ground, and generally up to 20m below the surface (or until the cone reaches a hard layer). The steel cone contains an electronic measuring system that records tip resistance and sleeve friction. As the cone goes into the ground, measurements are constantly sent back to the rig and recorded on a computer. Once complete, the holes are refilled.

This data helps inform the design of our work programme for Stage 3.

After Labour Weekend, you can expect to see some activity on and around the Riverside Drive stopbank as the contractor starts on access and preparatory works for Stage 3 of the SOS project.

Fencing policy for SOS

At our September SOS Community Reference Group meeting, there was discussion around fencing as part of the SOS project and who is covering the costs.

Here’s a summary:

• We have a Rivers and Drainage Fencing Policy, which was updated in 2022. This policy covers all rivers and drainage schemes.
• We have used this policy as a guide, but adapted it to be fit-for-purpose for rear boundaries in the SOS project area.
• As such, for landowners in the SOS project area, Regional Council is covering the cost of a conventional wire mesh, timber railed or timber paling fence type (e.g. pictured), to a maximum of 1.8m high (we will also include a pedestrian access gate to the stopbank if requested).
• Where an owner chooses to construct a fence of a different material or style, we will ONLY contribute the cost of a conventional wire mesh or timber paling fence to a maximum of 1.8m high.
• We will NOT contribute to any additional feature components that the owner wants included as part of the fence construction – such as shaped posts, end caps or trellis work, painting, mowing strips etc.
• In practice, this means we use a quoted cost for the standard fencing as the basis for any contribution to alternative style fencing. Note, any private fence construction requires a Bylaw Authority (which the landowner will need to arrange).

Cut and carry: Contractor notifications

Previously, our cut and carry contractors have been putting notices in residents’ letterboxes to let them know when the work is due to happen. However, this hasn’t always worked well as the contractor’s schedule can change (largely due to wet weather).

To ensure communications are more timely and efficient, we will be moving to an email and text notification system for those neighbours who would like notification of pending cut and carry operations. The email and text notifications will replace the letter drop notices.

Residents who would like to receive the notification, please email riversanddrains@boprc.govt.nz, and give us your email address and cellphone number.

DIY’ing? Remember, you might need a Bylaw Authority

Thinking of getting stuck into a bit of DIY this summer? Before you dig, plant or build on your property, check if you need a Bylaw Authority for your activity.

What is a Bylaw Authority? A Bylaw Authority may be required if your property is near a Regional Council flood defence (such as stopbanks, floodwalls, drains and pump stations). It is written permission from us to carry out your planned works, with conditions in place to make sure that what you’re wanting to do doesn’t affect the condition of these flood defences.

It’s not to stop you doing work – just making sure that whatever work you do doesn’t accidentally affect the integrity of our flood protection and drainage infrastructure (which is critical to helping keep the community safe in floods).

Some activities that may need a Bylaw Authority include:

• Planting and/or removing trees and shrubs
• Building and/or removing fences and garden sheds
• Building and/or extending a house, shed or deck
• Constructing or removing retaining walls
• Landscaping earthworks
• Installing, upgrading or removing an in-ground swimming pool

If you live in the SOS project area (i.e. your property borders the base of the stopbank), you are in a Bylaw Applicable Area and, therefore, most works will need a Bylaw Authority.

Our team are here to help you through the process.

Find out more or contact our team on riversanddrains@boprc.govt.nz