RFI - Stormwater Mgm Plan 20169 - SBSMP - Rev 4 (2)

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5.4     Vegetation Management and Weed Control
Conventional surface mulching of the bio-retention basins with organic material like tanbark,
should not be undertaken. Most organic mulch floats and runoff typically causes this material to
be washed away with a risk of blocking drains.

If weeds are observed within the bio-retention basin they shall be removed. Weeding will
generally involve manual removal of the species.

Vegetation planting densities are to be in accordance with the Landscape Architect’s design.
Where necessary a biodegradable erosion mat can be applied the basin batters to help combat
weed invasion and reduce the labour intensive maintenance requirements for weed removal.

Herbicides are not recommended as a means of weed control. If required, however, their
application is to be managed to avoid unintentional destruction of other vegetation or the
introduction of chemicals that may contaminate the stormwater runoff.

Where necessary, in areas that have been extensively weeded, the bio-retention basin shall be
replanted with similar planting densities using suitable native species in accordance with the
Landscape Architects design.

Inspection of the existing vegetation is to take place and any dead or diseased vegetation shall
be removed and replaced with suitable native species in accordance with the Landscape
Architects design.

The removal of plants, dead or diseased vegetation or weeds shall be disposed offsite at an
appropriate waste management facility.

All litter and debris present on the surface or batters of the bio-retention basins shall be
removed and disposed offsite at an appropriate waste management facility.


5.5     Validation Water Quality Testing
Validation water quality testing is not proposed for the site.


5.6     Equipment Needs
The equipment required to undertake regular maintenance to the bio-retention basins will be
standard hand held landscaping tools. No specific mechanical equipment is expected to be
required for the maintenance of the basins unless resetting is required (refer Section 5.11).


5.7     Occupational Health and Safety
The maintenance activities are to be undertaken in accordance with all current occupational
and workplace health and safety legislation, regulations, codes of practice or manufacturers
guidelines.




Bio-Retention Basin Operational Management and Maintenance Guideline