BBNE00529_0002_0001-REP-001-1-73 Eumundi-Noosa Rd SMP

3.6         Treatment Train Operation and Maintenance
In the context of development Sites and associated construction and building works, delivering bioretention basins and establishing
vegetation can be challenging. Therefore, bioretention basins require a careful construction and establishment approach to ensure the basins
are formed in accordance with the design intent. The following sections outline a recommended staged construction and establishment
methodology for bioretention basins as outlined within Healthy Waterways Technical Design Guidelines.

3.6.1       Construction & Establishment
The following is a proposed staged construction and establishment method:

3.6.1.1 Functional Installation
Construction of the functional elements of the bioretention basin will occur at the end of civil works construction along with the installation
of temporary protective measures. During the building phase, the protection will consist of a suitable geofabric covered with shallow topsoil
(e.g. 25 mm) and sacrificial turf layer until 80-90% of the building in the catchment is complete.

This is in alignment with Option 1 of the Construction and Establishment Guidelines (Water by Design, 2010). This guideline should be referred
to for the step-by-step sequence and sign-off forms.

3.6.1.2 Erosion and Sediment Control
An Erosion and Sediment Control program and plan will be prepared for the construction phase of the development. This will be completed
for the Site in the detailed design phase and is to be kept on Site and implemented for the duration of the construction phase.

3.6.1.3 Operational Establishment
At completion of the building phase, removal of any temporary protective measures along with accumulated sediment and the system
planted in accordance with the design planting schedule.

Vegetation establishment will be aided based on the following controls:

•   Weed control:
    Adopting high planting densities and if necessary, applying a suitable biodegradable erosion control matting to the batters will help to
    combat weed invasion and reduce labour intensive maintenance requirements. A heavy application of seedless hydro-mulch can also
    provide short term erosion and weed control. No matting or hydro-mulch is to be applied to the surface of the bioretention basin
    following the construction phase, as this will hinder filtration of stormwater through the filter media.
•   Watering:
    Regular watering of bioretention basin vegetation is essential for successful establishment and healthy growth. The frequency of watering
    to achieve the successful plant establishment is dependent upon rainfall, maturity of planting stock and the water holding capacity of
    the soil. The following watering program is generally adequate but should be adjusted to suit the Site conditions:
    Week 1-2          3 visits/week.
    Week 3-6          2 visits/week.
    Week 7-12         1 visit/week.

After this initial 3-month period, watering may still be required, particularly during the first winter. Watering requirements to sustain healthy
vegetation should be determined during ongoing maintenance Site visits.

3.6.1.4 Maintenance
The bioretention system will be maintained by the Council owner, who as the asset custodian, will be responsible for the on-going
maintenance of the water quality device. Operations and maintenance should be conducted in accordance with the Maintaining Vegetated
Stormwater Assets (Feb 2012) guideline.




73 EUMUNDI - NOOSA ROAD, NOOSAVILLE I BBNE00529_0002_0001-REP-001-1                                                                           11