Some areas in the Camden LGA are affected by levels of salinity that are high enough to damage buildings and service infrastructure. Salinity can also reduce water quality, threaten fauna and result in the degradation of vegetation and soils, including the loss of productive agricultural land.
This section seeks to ensure that consideration is given to the impact of new development on salinity processes, as well as the impact of salinity on new development.
- Minimise the damage caused to property and vegetation by existing saline soils, or processes that may create saline soils;
- Ensure development will not significantly increase the salt load in existing soils and watercourses;
- Prevent degradation of the existing soil and groundwater environment. For saline and sodic soils, minimise erosion and sediment loss; and
- Ensure concrete slabs, brickwork/masonry products, roads, above ground/underground infrastructure is appropriate for the saline conditions of the site.
- Groundwater recharge is to be minimised by:
- directing runoff from paved areas (roads, car parks, domestic paving etc) into lined stormwater drains rather than along grassed channels.
- lining of ponds and water sensitive urban design water bodies to avoid groundwater recharge.
- encouraging on site detention of roof runoff and use of low water demanding plants.
- encouraging tree planting, especially adjacent to watercourses.
- For road works within areas identified as a salinity hazard:
- disturbance of subsoil should be minimised.
- engineering designs incorporating considerations of salinity impacts are required.
- subsoil drainage is to be installed along both sides of all roads.
- roads should run along or perpendicular to the contours as much as possible.
- alternative footpath treatments will be considered if the proposal will reduce the need for watering.
- All development, where saline and sodic soils are identified, must incorporate soil conservation measures to minimise soil erosion and siltation during construction and following completion of development. Soil and Water Management Plans, prepared in accordance with Managing Urban Stormwater – Soils and Construction are to be submitted with each subdivision DA.
- All sediment and erosion controls are to be installed prior to the commencement of any works and maintained throughout the course of construction until disturbed areas have been revegetated/ established. Certification is required to be submitted to Council prior to commencement of construction.
- Salinity assessment of soil and ground water must be undertaken and submitted to Council with the development application for subdivision. Investigations and sampling for salinity should be conducted in accordance with the requirements of the Heritage (Department of Premier and Cabinet) booklet Site Investigations for Urban Salinity.
Note: A salinity assessment may be requested for development applications on land that does not have a salinity management plan restriction on title.
- Where salinity is identified on the site and a salinity report is prepared the report must also contain a Salinity Management Plan having regard to the following issues and construction requirements from Australian Standards:
- What impact will the development have on existing salinity levels in the soil and ground water,
- What impact will salinity have on the type of construction proposed which may include the method of construction, water treatment devices, etc,
- AS 2159: Piling Design and Installation,
- AS 3600 Supp1: Concrete structures,
- AS 3700: Masonry Structures,
- AS 2870: Residential Slabs and Footings,
- any other relevant standard or provision referred to for salinity under the BCA, and
- Council’s Engineering Design Specifications.
In the absence of a salinity management plan, all works proposed on the land must be designed to achieve the requirements of Council’s current Engineering Design Specification.
- Where a development site is considered a salinity hazard:
- Cut and fill must be minimised.
- Subsoil drainage should be installed along both sides of roads.
- Upgrade from Council’s standard stormwater requirements to suit the saline environment.
- Building works are to be in accordance with Councils current Engineering Design Specification, or in accordance with a salinity assessment which demonstrates an acceptable solution to manage salinity impact on building works.
- Reference should also be made to the WSROC Salinity Code of Practice (as amended).
- For service installation within areas identified as a salinity hazard, the following must occur:
- Ensure that no leakage occurs from water, sewer and stormwater pipes.
- Services should be joint trenched where possible.
- Where services cross roads, conduit at least should be laid at the time of the road construction.
- Transverse service connections (across roads) must be laid in conduits placed at the time of road construction if the service is not laid out at that time.
- Water supply pipes must be copper or a non metal acceptable to Sydney Water.
- Sewer pipes must be unplasticised Poly Vinyl Chloride (PVC) or other material acceptable to Sydney Water.
- The use of recycled waste water for the watering of domestic gardens should be minimised and in some cases will not be permitted.
- For public / private infrastructure, including but not limited to parks, roads, stormwater systems and utility installations, in the absence of a salinity report, all works proposed must be designed to achieve the requirements of Council’s current Engineering Design Specification.