Conditions Today and Programs Underway

The Manly Lagoon Integrated Catchment Management Strategy (2004) and Estuary Management Plan (1998) were developed jointly between Manly and Warringah Councils to work to improve Manly Lagoon. Recent reports indicate that the Lagoon is now highly modified and sensitive to further degradation. The stormwater quality in the three creeks feeding the Lagoon, fails to meet national aquatic ecosystem guideline levels for nutrients, water clarity, and algae levels. As a result, the water quality in the lagoon is very sensitive and dependant on rainfall. The lagoon is not currently suitable for recreational activities such as swimming, wading, fishing, and boating, due to high levels of faecal pathogens arising from stormwater runoff and sewer pollution.

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This confirms that the source of the Lagoon’s ongoing health problems lie in the surrounding urban catchment. This is why Manly and Warringah Councils have developed integrated plans and strategies to prevent further degradation, and to work to improve the Lagoon health. There is also much that residents in the catchment can do. Manly Council and Warringah Council are currently undertaking a range of initiatives to improve the quality of stormwater and the Lagoon condition:-

  • Improved land use management (for example, increased water sensitive urban design)
  • Stormwater capture, detention, re-use, and infiltration to reduce volumes to waterways
  • Pollutant interception in the catchments (for example use of gross pollutant traps, nets, litter baskets, street sweeping and other storm water quality improvement devices)
  • Removal of existing pollution / targeted rehabilitation (for example dredging, see Manly Lagoon Rehabilitation Works)
  • Working with major stakeholders in the catchment such as Golf Courses. (For example a partnership project between the Manly Environment Centre, Manly Council, and the four Golf Courses in the Catchment in 1995/96 was developed to improve golf course environmental management standards. Outcomes of this successful project were adopted by the EPA as a model for NSW.)
  • Restoration works on the three creeks (Brookvale Creek, Manly Creek, Burnt Bridge Creek) (for an example see Burnt Bridge Creek Integrated Restoration Project)
  • Replanting of riparian vegetation, weed removal and creek bank restoration, including the “Revive the Reeds” project, construction of new wetlands, Mermaid Pool restoration works, and Manly’s “Hop in and Help Program” (see Vegetation and Creek Bank Restoration)
  • Working to better understand fish and wetland bird community abundance and diversity through studies in the catchment and lagoon
  • Working to better understand nutrient and sediment loading from the catchment
  • Improving public awareness of dog owners and impacts of domestic animals on riparian vegetation, native birds and water quality

A range of community orientated initiatives, including:-

  • Drain stenciling works by Manly Council and the Manly Environment Centre to improve public education (see below photo in 2010)
  •  “The Great Estate” was an industry and business education program for companies in the Balgowlah Industrial estate
  • “Seachange” was a community education program

Manly Council, Warringah Council, and Sydney Water are also currently undertaking a number of programs to detect and rectify issues in private sewer connections and sewer mains, including:-

  • Measuring the quality of storm water in drains discharging to Manly Lagoon in dry weather, to determine if there is any sewage leaking into the system
  • Inspecting, using smoke or dye to see if there are leaks
  • Cleaning and inspecting all high-flow sewers with closed circuit television cameras to prevent blockages and sewers spilling in the future

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Drain stencilling in Manly undertaken in December 2010