Many low lying coastal areas have naturally occurring materials known as acid sulfate soil, including the City of Botany Bay.
These soils, when inappropriately disturbed, can become very acidic due to exposure to oxygen. Areas likely to be affected include the Botany Bay foreshore, creek lines and reclaimed areas. Excavation can also disturb acid sulfate soils further afield from these locations.
Any developments or civil works that involve the disturbance of soil below the groundwater table or the disturbance of sediments within Botany Bay have the potential to disturb actual or potential acid sulfate soils. The soils can form sulfuric acid that can leach into the surrounding area acidifying neighbouring drains, wetlands, creeks, estuaries and bays, causing severe environmental damage. It can also impact on infrastructure by causing serious damage to steel and concrete structures such as the foundations of buildings.
There are five classes of land when categorising risk from acid sulfate soils. Each Class has corresponding acid sulfate soil risk management requirements. Further information can be found at:
All Development Applications are assessed for the likelihood of acid sulfate soils onsite, and depending on the risk class, appropriate management measures are required during demolition, excavation and construction.
Further general information on acid sulfate soils can also be found at:
Department of Environment
NSW Office of Environment and Heritage
Sediment and Erosion Control
Uncontrolled stormwater discharges from urban catchments have significant harmful effects upon the environmental health and amenity of creeks, rivers, wetlands, groundwater systems, estuaries and lagoons.
Disturbance of soil for building, construction and landscaping can cause pollution if not managed correctly. The Botany Bay City Council requires the implementation of controls for solid and water management for developments, as outlined in the Part 3G of the Development Control Plan 2013.
The following information must be provided as part of documentation of Development Applications to Council:
A Development Application must include an:
- Erosion and Sediment Controls Plan for sites with an area of 2500m2 or smaller, or
- Soil and Water Management Plan for sites with an area greater than 2,500m2.
Managing Urban Stormwater - Soils and Construction 4th ed. March 2004 and Planning for Erosion and Sediment Control on Single Residential Allotments Provide guidelines for the preparation of these plans.