Thursday, December 17, 2020

Fresh ideas for restoring "stinky" creeks

Discolouration of water at Carina Creek pre-restoration
Discolouration of water at Carina Creek, prior to works

Carina and Kareela Creeks in Sutherland Shire are both constructed tidal creeks, formed when the original bays were reclaimed during the 1960’s and 1970’s. Kareela Creek is also the outlet of one of the biggest stormwater catchments in Sutherland Shire LGA, and Carina Creek is subject to small stormwater flows. Sediment build-up in the creeks over years caused the stagnation of waters, affecting the water quality and vegetation and generating hydrogen sulphide (rotten egg) odours which affected neighbouring residents.

The aim of projects undertaken by Sutherland Shire Council over the past couple of years was to restore the natural tidal flows to improve water quality and alleviate the odours at a reasonable cost.

Carina Creek works were undertaken first during the winter months of 2018 and following the success of Carina Creek, Kareela Creek works were undertaken during the winter months of 2019 using the same methodology.

This webinar, presented by Phillippa Biswell from Sutherland Shire Council Environmental Science team, which was recorded on Thursday 17 December 2020, discusses the issues faced, what the options were, why certain solutions were chosen, methodology details, and plenty of before, during and after photos showing the effectiveness of the works.

Phillippa works in the Environmental Science Unit on environmental projects often dealing with contamination issues, acid sulphate soils, and erosion, as well as the associated aspects such as water quality that tie into these issues. She has been working in this role for the past 16 years.

We’re excited to be sharing this case study with you – Phillippa’s work, with the assistance of Nathan Varley, has provided an understanding of the sulphate cycle in creeks, leading to a methodology to restore stinky creeks which Sutherland Shire Council is now using at multiple sites.

Watch the recording...

YouTube Video

This short webinar as part of our strategic Education and Capacity Building Program to foster a shared understanding of issues and solutions for best practice management of urban waterways.

Presenter: Phillippa Biswell

YouTube Video

Southern Dredging was contracted to complete dredging for Kareela Creek to remove excess sediment that has silted up in the tidal creek bed.