Landcom Book 4 Maintenance - WSUD

Water Sensitive Urban Design
6.3 Construction
Certification and
Compliance
The construction of a vegetated WSUD
strategy requires coordination between
the civil and landscaping contractors.
Civil contractors are responsible for the
construction of the functional elements
of a treatment system, while landscape
contractors are responsible for the
initial plantings and management of
the treatment system to ensure plant
establishment is successful and meets the
design brief.
Consequently, construction certification is
required from both civil and landscaping
contractors as documented in the revised
Water by Design (2009) documentation.
The suggested construction certificates
for constructed wetlands, bioretention
systems and sediment basins/ponds are
described in the table below.
Additionally for bioretention basins,
certification is required from the soil
supplier to ensure the soil specifications
of the filter media meet the requirements
documented by the Facility for Advancing
Water Biofiltration (FAWB) (refer to section
4.04).
The certification outlined above should
form the basis of compliance for WSUD
elements. However, to minimise rework
due to non-compliance issues, it is
suggested that inspections/meetings be
scheduled as follows (refer column over):
1) Pre-start meeting: Ensure all
contractors are aware of the key issues
for each stage of construction. For
example, compaction requirements
for filter media.
2) Inspection of all functional elements
(as completed) of the treatment system
(for example, the under-drainage for a
bioretention should be inspected prior
to the gravel being inserted around
the pipes).
3) Inspection of sediment control
structures to ensure vulnerable
elements within the treatment system
are isolated from storm flows as
dictated in the design documentation.
4) Inspection of plant establishment
(if required) to ensure species and
densities are as per the design.
Continual inspections should
be scheduled to check plant
establishment.
5) Final inspection of plant establishment
and civil works.
The scheduling of the above inspections
within the three main construction stages
is given below. Example inspection and
sign off sheets for WSUD elements are
given in Appendix A.
Civil Certification
Designers certification of functional elements
Civil certification that functional elements have been constructed as
per the designers certification
As constructed survey, drawings and photos
Landscape Certification
Designers or ecologist sign off of plant species
As constructed drawings identifying species and plant density
Book 4 | MAINTENANCE 47