10.    CHAPTER:  Access and Maintenance

10.1    General

A creek rehabilitation project can be done very well but if maintenance is not kept up then the project can fail and much of the time, effort and money that went into the project.  A rehabilitation project is similar to any other piece of a landholders infrastructure be it fences, sheds or pasture, they all need regular maintenance.  If a wooden house is not painted occassionally the boards will rot out relatively quickly.  If weeds are not contontrolled on a rehabilitation site they will often swamp most of the newly planted vegetation and cause additional problems like willows choking waterways.  Or if fences are not maintained then stock will get into the rehabilitation site and damage the project.

One advantage of a well designed and executed rehabilitation plan is that the native vegetation component once well established, will make it considerably harder for new weeds to become established.  This natural protection against weeds means that the amount of time spent controlling weeds will can drop off markedly.

10.2    Verge access track

A Verge access is desirable in all rehabilitation project irrespective of whether there is a fence or not.  The Verge access track is typically 3 -4m wide and runs either directly on the inside, creek side, of the fence protecting the rehabilitation project or at the boundary line between the rehabilitation project and the rest of the property.

The Verge access track is a grass track which enables vehicle and easy pedestrian access along the length of the rehabilitaion project.  The benefits of the Verge access track are:

  • Vehicle access all along the length of the rehabilitation project
  • The ability to use a weed spray hose and reel without getting caught on the fence
  • Ability to easily visually inspect the fence on both sides
  • Minimise branch drop on the fence
  • Plants growing in a rehabilitation site will typically create a strip of less successful pasture or crop next to them by restricting the amount of ground  moisture they have access to.  If this strip is located where the access track is then the farmer is not losing a great deal of pasture anyway and the grass grownign on the access track will be easier to maintain.

10.3    Creek access track

Creek access tracks (CAT) are typically created when the total width of the biodiveristy corridor along a creek exceeds 50m and the when the creek channel is particularly wide and or deep.  There will be instances where a CAT is either not desirable or practicle for example when channel banks are too steep.  While a Verge access track runs along the inside of  a creek fence a creek access track is created to cross and or for limited sections to run within the creek channel itself.  As with the Verge acces track the primary reason for creating a CAT is to make the rehabilitation project more cost effective. 

Benefits of having a creek access channel:

  • Spraying up onto the chanel banks rather than spraying down from the Verge means less herbacide is likely to fall on the water in the creek 
  • Spraying up onto the chanel banks rather than spraying down from the Verge leads to a better kill of weeds particularly if there is a dense infestation of blackberries
  • The costs of ongoing weed control are significantly reduced
  • Planting costs are reduced
  • Site inspections are made considerably easier
  • Pest control is considerably easier
  • Recreational and educational activities are far more enjoyable and practicle.

10.4    Creek access track construction

While CATs are highly desirable in many situations it is important the appropriate permits are obtained before any works in or near the channel occur and that an experienced contractor and works supervisor are employed.

The aim of a CAT is to provide a graded access track at suitable points along the creek channel itself.  The CAT should be designed to facilitate creek maintenance and improved access to the low flow channel for pedestrian traffic.  The CAT is not intended to permit access to onroad vehicles and should be of a width to preclude onroad vehicles using it.

The ideal method of creating a CAT is for an excavator operator experienced in waterway works using a 3-5 ton excavator to establish a 3m wide graded track along the creek for the length of the project site.  The excavator driver should be working to designed which takes advantage of the existing channel conditions including only entering the channel where appropriate and using terraces within the channel where ever possible.  Unless actually crossing the creek the CAT should stay away from the Low flow channel where ever possible.

Given the dynamic nature of many creeks it is likely that over time the CAT will 
be washed out in places or have overhanging areas of bank slump down on the track.  In order to minimise erosion stay as far from the Low flow channel bank as possible and ensure that the excavator driver batters back the bank to a stable angle where possible above the track.

While it is inevitable that over time the track will in places become blocked and that keeping the track fully open is not practicle, this does not invaladate the concept of a CAT.  Even with occassional blockages along its length the general outline of the track and its basic value, except in the most dynamic of creek environments, as a graded pedestrian track should last for more than 10 years.

As well as carefully choosing the location for the CAT it is recommended that as soon as the track has been created it is sown down with an appropriate grass species.  In this way the chances of significant erosion occuring during high flow events is reduced.  An additional benefit of immediate seeding with grass is that is will reduce the level of weed recruitment on the areas where the earth has been disturbed.

10.5    Weed and pest control

Awaiting content ...