Lawson, Blue Mountains ecological restoration project 2011-13 and other projects

1. Ecological restoration project  2011-2013

In 2011, following careful planning by our BMCC Bushcare Officer, the bushcare group commenced a small ecological restoration project on the former Lawson golf course site, with the prime objectives of restoring a former natural woodland site that many decades ago had been converted to a mowed grass area, and also widening the riparian corridor of Lawson Creek and swamp in order to restore ecological function there. The project area extended over approximately 2000 square metres.

The Society for Ecological Restoration Australasia maintains a set of “National Standards” for the practice of ecological restoration, and the Lawson project met these standards.

  • The project aspired to restore a very high level of ecological function to the site.

a. To completely restore indigenous bushland and ecological function to a mowed strip of grass where the bushland had been totally destroyed for approximately eighty years.

b. To provide a further layer of natural environmental protection to Lawson Creek and swamp by restoring ecological function to its riparian corridor and associated terrestrial fauna habitat.

c. To restore further ecological function to Lawson Creek by enhancing its water quality and aquatic fauna habitat.

The project also enhanced ecosystem services on the site, both water quality and amenity, as the creek borders popular walking tracks and is part of the Hawkesbury-Nepean catchment.

  • Targets, goals and objectives were set.

Target: restoration to E. piperitaAngophora costata woodland status;

Goals: maintain and renew planting regime over three years; maintain and renew fencing and interpretive signage over three years to protect natural regeneration; ongoing monitoring for shrubby weeds reducing to minimum of six monthly monitoring for weeds and vandalism;

Objectives: obtain administrative approval for project and liaise with other stakeholders; two sessions of fencing to delineate non-mowing area; design, obtain and erect interpretive signage; commence replanting of shrub layer on monthly basis; facilitate and encourage natural regeneration; remove woody weeds as encountered.

  • There was extensive and ongoing community involvement, both in the form of the local volunteer bushcare group, a visiting volunteer community group, local resident interest, consultation with Blue Mountains City Council (land managers) staff and incorporation of the project into the Blue Mountains City Council 2019 Masterplan for the area.
  • Contemporary and validated restoration techniques were used i.e. replanting with indigenous flora sourced from a specialist native nursery, and natural regeneration. The relevant administrative authorities were consulted, approvals obtained, and other land-users were informed about the project.
  • The intervention level was reasonably appropriate. The original Open-forest on the site had been totally destroyed for eighty years or more, so protective fencing, replanting and facilitation of natural regeneration were suitable responses. Indigenous flora species, grown from locally sourced seed (local provenance), were obtained from a Blue Mountains’ specialist native plant nursery. Natural regeneration of indigenous flora via dispersed seed from the adjoining Open-forest flourished. Tree seed for nursery propagation is hard to collect due to tree height, and natural regeneration helps to overcome this problem.With hindsight, less planting could have been used, as natural regeneration was very strong, particularly of Eucalyptus sp.
  • The adjacent natural woodland (E. piperitaAngophora costata woodland) was utilised as a reference ecosystem, or restoration model.

(See: Society for Ecological Restoration Australasia, National Standards for the Practice of Ecological Restoration in Australia  2nd edition 2018 http://seraustralasia.com/standards/National%20Restoration%20Standards%202nd%20Edition.pdf )

2011-13

Riparian planting area August 2013

Our streams require wide stands of intact native vegetation along their banks, to protect against urban impacts  Photo: P.Ardill

The project aim is to widen this woodland riparian zone

The project aim was to widen the forest area that borders Lawson Creek  Photo: P.Ardill

The planting corridor was well sign posted.

The planting corridor is approximately 10 metres wide and 200 metres long Photo: P.Ardill

Pur BMCC bushcare officer enjoys planting days! May 2011

Our BMCC Bushcare Officer enjoys planting days!  May 2011 Photo: P.Ardill

Riparian planting Aug 2013

Riparian planting Aug 2013 Photo: P.Ardill

2016

The project is on track to meeting its ecological objectives: little maintenance is required, the re-established vegetation is thriving, and there appears to be good diversity of indigenous flora species present, including trees. It is anticipated that existing weedy grasses may well be eradicated by natural mulching and and shading out in the future. Many thanks to our Bushcare Officer for initiating this project.

Natural regeneration of native trees. Nursery propagation of native trees can be difficult as seed is hard to collect due to tree height. Dec 2016

Natural regeneration of native trees Dec 2016 Photo: P.Ardill

 

Another layer of shrubs and trees for Lawson Creek, June 2016

Another layer of shrubs and trees for Lawson Creek, June 2016 Photo: P.Ardill

Four years of growth, Dec 2016

Four years of growth, Dec 2016 Photo: P.Ardill

2017

Lawson Creek riparian planting, October, 2017

Lawson Creek riparian regeneration, October 2017. Photo: P. Ardill

Lawson Creek riparian regeneration, October 2017

Lawson Creek riparian regeneration, October, 2017. Photo: P. Ardill.

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2. GWH upgrade 2009

As part of its redevelopment of the Great Western Highway at Lawson, the then RTA (RMS) had to manage the stormwater flows of the new four lane road, and proposed the construction of a large stormwater detention basin south of the GWH, near the end of Ferris Lane and adjacent to Lawson Creek and swamp. From the outset of this project the Bushcare Group was registered as a stakeholder and was extensively involved in negotiations with the RTA Lawson project management team in order to mitigate the potential adverse environmental effects of this stormwater work.

Detention basin construction by RTA adjacent to lawson creek swamp Nov 2009

Detention basin construction by RTA adjacent to Lawson creek swamp Nov 2009 Photo: P Ardill

Detention basin construction by RTA July 2009

Detention basin construction by RTA July 2009  Photo: P Ardill

Major issues were the route of the pipeline from the GWH (minimising bushland impacts), the size of the detention basin (not too small), the rate of discharge flow from the detention basin into Lawson Creek (not too strong), the route of the channel into Lawson Creek (avoiding the swamp) and the possibility of building holding ponds as part of the stormwater dispersal system, as an alternative to a channel through the swamp.

The detention basin channel area has, to a certain extent, regenerated well, and this is largely due to the planting of Tea-tree (Leptospermum polygalifolium) by Bushcare Group memebers in 2011 and ongoing weeding. However, it is infested with Juncus microcephalus, and in the future the seed from this weed will continue to flow into Lawson Creek.

Detention basin outflow channel cut through swamp July 2009 Photo: P Ardill

Detention basin outflow channel cut through swamp July 2009 Photo: P Ardill

Detention basin channel, Jan 2017

Same detention basin channel area, now well vegetated, Jan 2017 Photo: P.Ardill

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3. Waratah Street 2010 & 2016

The unformed section of Waratah Street between Honour Avenue and New Street borders the upper reaches of Lawson Creek and its tributaries, and weed growth here is prolific. The area received bush regeneration and stream management attention in 2010.  Noticeable weed issues here are Privet, Scotch Broom, Japanese Honeysuckle and Blackberry.

Waratah Street (east) slashed for weed control Jan 2010
Waratah Street (east) slashed for weed control Jan 2010 (photo BMCC)
Rock lining of Lawson creek tributary to minimise sediment flows, Waratah street Jan 2010
Rock lining of Lawson Creek tributary to minimise sediment flows and support the unvegetated and eroded banks, Waratah Street Jan 2010 (Photo BMCC)

In July 2016 the bushcare group removed extensive amounts of Privet, Scotch Broom, Cootamundra Wattle and Tree Lucerne from the Waratah Street site (eastern section). These weeds can easily form dense thickets and encroach on and compromise the original bushland around the upper catchment of Lawson Creek. We try to maintain a weed free buffer zone around the good bush, but there still are dense patches of weed (Privet, Blackberry, Japanese Honeysuckle) in this area.

Wall of weeds, Waratah Street, August 2016
Wall of weeds, Waratah Street, August 2016 Photo: P.Ardill
Diversity and beauty, intact Waratah Street bushland, July 2016

Diversity and beauty, intact Waratah Street bushland, July 2016  Photo: P.Ardill

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