Drainage improvement works

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Council is responsible for the management of stormwater in streets and the underground drainage pipe network. This system takes stormwater from houses, footpaths, and roads underground into large diameter concrete pipes where it will eventually discharge to the Patawalonga at Glenelg and into the ocean.

Typically nearly all creeks In Unley are privately owned and for information on urban creeks and the responsibility for their care and control please refer to the Brownhill Creek web site.

Stormwater pipes from your house to the street are the responsibility of the private land owner, and if you wish to install or replace a stormwater outlet for your downpipes please refer to the works on public land form(PDF, 264KB) .

What will the works involve?

Stormwater works often involve deep excavation into the roadway (1.5m or greater) to install concrete pipes. Part of the stormwater system’s effective operation is having side entry pits to capture the water and convey it underground to the newly installed pipes so typically there will also be excavation of the kerb and verge to install large pits.

The alignment of the stormwater pipe is often dictated by service utilities and avoiding clashes with Gas, Water, or Sewer. While we aim to construct adjacent the kerb to minimise disruption to traffic and residents sometimes it is unavoidable to have the pipe close to the centre of the road meaning road closures.

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Why do we do stormwater upgrade works?

Common practice is to provide undergound pipes for the Minor 1 in 5 year storm (20% chance it will occur in any given year), while the Major 1 in 100 year storm (1% chance it will occur in any given year) is too large to be contained within pipes and is designed to travel overland in the road reserve:

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Council undertakes stormwater works for one of two reasons:

  1. Age of the Pipe or Pits (renewal)

    This is where the existing pipes that were constructed often 70 to 100 years ago are structurally showing signs of deterioration and failure and must be replaced.

    Council undertakes regular audits of its pit and pipe network and forecasts when these works will be required so it can adequately plan and budget in advance.

  2. System Capacity (new/upgrade)

The construction of new pits and pipes is undertaken when the existing road reserve is not sufficient to convey flows and there is a flood risk to properties, or where the Minor system flows are too high and create large flows in the street causing excessive nuisance to the community.

How will you know if works are planned?

Residents directly affected by the works will receive a letter with a description of the works proposed approximately two months before the intended start date, or longer where the works will cause a major long term disruption.

Just prior to the works beginning residents will receive a second letter to let you know the work is about to commence and explain what the works involve as well as include important contact details and what to do on the day of the works.

 

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How do we keep the community safe?

While we try to minimise the impact to residents, unfortunately some inconvenience may occur such as:

  • The road will likely be closed during works,
  • Access to properties will be limited for short periods of time, during works hours where possible we will aim to provide access to properties from either end of the street and have it opened to residents only upon the completion of works each night,
  • Generally works are confined between 7am and 6pm Monday to Saturday,
  • Works may involve considerable noise, including horns and reversing beeping to keep workers and the community safe.

When construction works are occurring your street is a work site and everyone's safety is important so please take care and listen to construction crews who are approachable and willing to help if you need. Alternatively, please call the contact person listed in the letter.

To minimise impacts we generally try to plan and work around holidays and highly trafficked areas. Our time lines may change due to unforeseen circumstances, this makes it difficult to notify affected residents earlier.

Stormwater works frequently asked questions

Bin collection has occurred and because of the works my bin was missed, should I leave it out?

Please ensure bins are placed out by 6am on the normal day of collection, Council works with our contractors to coordinate waste collection around construction works, however sometimes bins may be missed. Please leave your bin out and we will endeavour to pick it up the following day. If this doesn’t happen please ring Council on 8372 5111

Will the contractors change my stormwater outlet for my downpipes?

No, we typically don’t change any stormwater outlets and these will remain in place discharging to the kerb. All our works will be done within the roadway deep underground.

Why is it taking so long?

Unfortunately laying stormwater pipes is a long and expensive process. It first requires excavation to the correct depth, the installation of a bedding layer, and then carefully lifting the pipe in and joining it to the other sections. Often there are services to work around (water, gas, electricity) and tight spaces for workers. The pipe then needs to be carefully backfilled to make sure there is no settlement of the soil and that no excessive loads go onto the pipe to cause cracks or damage.

Construction feedback

Have we recently completed drainage construction works in your street? Let us know how we did by completing a feedback response: Construction Works Feedback

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