Collaroy Stormwater Outlet

Damaged Outlet Pipe

The Collaroy outlet pipe provides an outlet for stormwater from the Collaroy catchment. The reinforced concrete structure extends some 85 meters from the seawall into the surf. It was last rebuilt in the 1970s, and its outer walls have deteriorated to the point that they now need replacing.

Upgrading our critical stormwater infrastructure

Warringah Council is considering two options to upgrade the ageing Collaroy stormwater outlet.

The options are:

• Middle Beach Option: replacing the existing stormwater outlet at it's current location  
• Southern Beach Option: diverting the alignment of the outlet adjacent to the pool at the southernmost end of Collaroy Beach

Warringah Council is keen to answer questions and hear feedback from you. 

Community Information Session

Collaroy Beach – marquee located near Collaroy Surf Life Saving Club

Saturday 24 March 2012

11am – 2pm

You can also have your say ... 

• Online at yoursaywarringah.com.au 
• Phone 9387 2600

 

 

 

 

 

 

 

 

Investigation of Alternatives

Council previously assessed several options which included:

•   Replacement outlet at current position
•   Very short outlet (in the same position)
•   Very long buried outlet (in the same position)
•   Divert to existing pipe at southern end of beach (near rockpool)

The objective of these studies was to evaluate, assess, and prepare designs to:

• Ensure the safe and effective disposal of stormwater
• Ensure that the new stormwater outlet does not restrict any future upstream flood alleviation works
• Maintain water quality in the rockpool and beach area
• Minimise any impact on the beach profile and form
• Safely decommission and remove the existing outlet structure

The studies also included geotechnical investigations, a review of environmental factors and cost assessments.