Boundary Creek and Big Swamp remediation

Barwon Water continues to progress the implementation of its Boundary Creek, Big Swamp and Surrounding Environment Remediation and Environmental Protection Plan, with the plan’s 2020/21 annual report submitted to Southern Rural Water.

Highlights from the report include:

• A continuing recovery trend of groundwater levels in the Lower Tertiary Aquifer, with groundwater levels through Big Swamp tending to be higher during the 2020-21 monitoring period compared to the 2019-20 period, particularly during the summer
• An increase in the pH of the surface water discharging from Big Swamp during the 2020-21 monitoring period compared to the 2019-20 period
• An overview of works completed in 2020/21 for both the remediation of Big Swamp & Boundary Creek, and the Surrounding Environment Investigation
• Refined surface and groundwater modelling for Big Swamp based on the full seasonal data set for groundwater levels and surface water flows within the swamp and Boundary Creek collected in 2020/21
• An overview of community and stakeholder engagement
• Potential to investigate method for treating water within Big Swamp to reduce acidity levels.

Barwon Water Managing Director Tracey Slatter said the annual report showed good progress was being made in the long-term plan to remediate the confirmed environmental impacts from historical management of groundwater pumping of the Barwon Downs Borefield, and investigate if surrounding areas within the regional groundwater system were also adversely impacted.

“The remediation plan’s implementation is progressing and yielding some early positive results in our adaptive approach.

“The plan is based on a wide range of technical assessments and investigations, experts from various specialist fields and input from our remediation working group and their nominated technical experts”

Ms Slatter thanked the members of the community and stakeholder working group that provided valuable advice into the development of the remediation plan over 18-months and who continue to provide oversight and feedback on implementation of the plan.

“We remain committed to keeping the local community and key stakeholders informed regarding the progress of remediation and to sharing the findings and outcomes of the plan.

“We thank remediation reference group members for their ongoing contribution to the remediation process and look forward to continuing to work with them over the coming months and years as we implement the plan, share data and adapt the plan based on observed outcomes.”

Barwon Water continues to progress the implementation of its Boundary Creek, Big Swamp and Surrounding Environment Remediation and Environmental Protection Plan, with the plan’s first annual report submitted to Southern Rural Water.

Highlights from the report include:

• a continuing recovery trend of groundwater levels in the Lower Tertiary Aquifer
• a summary of the full seasonal data set for groundwater levels and surface water flows within Big Swamp and Boundary Creek that will be used to help refine surface and groundwater modelling for Big Swamp, which should be finished by the end of this year
• completion of Autumn macro-invertebrate sampling in Boundary Creek and the Barwon River, which follows sampling undertaken in Spring last year and shows that impacts from Big Swamp were confined to immediately downstream of Boundary Creek, and
• progressing the planning, design and approvals for installation of five stream gauges as part of the Surrounding Area Investigation.

Barwon Water Managing Director Tracey Slatter said the submission of the annual report was another important step in the long-term plan to remediate the confirmed environmental impacts from historical management of groundwater pumping of the Barwon Downs Borefield, and investigate if surrounding areas within the regional groundwater system were also adversely impacted.

“The plan represents 18-months of work by Barwon Water, its remediation working group members and technical experts, so it’s great to see it progressing and some early positive signs in our adaptive approach.”

Meanwhile, the community and stakeholder working group that provided valuable advice into the development of the remediation plan over 18-months will continue to provide oversight and feedback during its implementation.

Barwon Water continues to progress the implementation of the remediation and environmental protection plan (REPP) for Boundary Creek and Big Swamp, with the plan’s first quarterly update submitted to Southern Rural Water.

The update, along with the results of two other reports – the Big Swamp Acid Sulfate Soil Study and the latest Barwon River Macroinvertebrate sampling report - are available to read on Barwon Water’s dedicated project website.

Barwon Water is remediating the confirmed impacts from historic management of groundwater pumping of the Barwon Downs Borefield, which was relied upon heavily during the millennium drought.

Managing director Tracey Slatter said the first quarterly update was an important milestone in the remediation plan, showing the progress beginning to be made in the detailed design phase of the REPP.

Ms Slatter said that the findings of the Big Swamp Acid Sulfate Soil Study confirm that maintaining the swamp in a saturated state will support the remediation.

Impacts from historic management of groundwater pumping of the Barwon Downs Borefield included the reduction of flows in Boundary Creek and the subsequent activation of acid sulfate soils in Big Swamp, resulting in acidic water discharging to Boundary Creek downstream of the swamp.

The quarterly update also provides information on the surrounding area investigation plan and the ongoing commitment to work with the community on the implementation of the REPP, with the details of ongoing community involvement to be worked through.

A dedicated community and stakeholder remediation working group and its nominated independent technical experts provided valuable advice into the development of the proposed remediation plan over an 18-month period.

Members of the group – which met 10 times and included representatives from LAWROC, Corangamite Catchment Management Authority (CCMA), Colac Otway Shire Council, Environment Victoria, Upper Barwon Landcare Group, Boundary Creek landowners and other interested community members – continue to be updated on the progress of implementation of the plan.

Key requirements of the section 78 notice and the REPP is the provision of quarterly updates to Southern Rural Water to report on progress with implementation of the plan, as well as an Annual Report.

The Annual Report is required to be submitted to SRW and made publicly available by 30 September each year.

In addition to the information contained in the quarterly updates, the Annual Report will provide more detail from technical investigations, monitoring data, and measure how the REPP is tracking against its success targets.

Barwon Water is looking forward to getting to work following acceptance by Southern Rural Water of the proposed remediation and environmental protection plan for Boundary Creek, Big Swamp and the surrounding environment.

Barwon Water submitted the proposed plan to Southern Rural Water on December 20 last year and, after incorporation of Southern Rural Water’s feedback into the plan this week, is excited to immediately implement the adaptive management approach outlined in the plan.

Barwon Water managing director Tracey Slatter said that the action in the plan to keep Big Swamp wet via provision of supplementary flows to Boundary Creek was already under way.

“By keeping the swamp wet, the plan aims to stabilise the acidification process that takes place due to the drying and wetting of the acid sulfate soils within the swamp, and reduce the risk of acid flush events in Boundary Creek in the long-term.

“In addition to maintaining the supplementary water releases, the first step in the adaptive plan includes continued collection of data to refine the design of the preferred remediation option, which is to install hydraulic barriers to slow and spread the flow of surface water through Big Swamp.”

Other early measures in the plan relate to the surrounding area investigation to ascertain if other areas within the regional groundwater system have been adversely impacted by historical management of groundwater pumping.

Barwon Water will share the outcomes of the assessment of these other areas with Southern Rural Water to determine what remediation steps need to be taken if environmentally significant impacts are confirmed.

Barwon Water will provide quarterly updates to Southern Rural Water as it implements the plan.

“We are looking forward to working with Southern Rural Water over the coming months and years as we implement the plan, share data and adapt the plan based on observed outcomes.”

Ms Slatter said the remediation plan was a clear statement of Barwon Water’s unwavering commitment to delivering successful environmental outcomes and working with the community.

“We remain committed to keeping the local community and key stakeholders informed regarding the progress of remediation and to sharing the findings and outcomes of the plan.”

Barwon Water will host a meeting with its Remediation Working Group members and their nominated independent technical experts to share Southern Rural Water’s feedback on the Remediation Plan.

Barwon Water will also invite the working group members to say how they and the broader community would like to be involved as the plan is implemented.

The remediation plan responds to the requirements of a Ministerial Notice issued to Barwon Water under section 78 of the Water Act 1989.

Barwon Water is hosting an information session to update the community on the Boundary Creek and Big Swamp remediation project.

The session will provide key information on the proposed remediation plan that has been submitted to Southern Rural Water. Members of the project team will be available to discuss any questions.

Event details:

Where: The Eastern Hub (Members Room), Eastern Reserve, Hopkins Street, Winchelsea

When: Wednesday 29 January 2020

Time: 5pm to 7pm

Barwon Water is hosting information sessions to update the community on the Boundary Creek and Big Swamp remediation project. We will include an update on the field program and development of the remediation plan. Members of the project team will be available to answer any questions.

Following ongoing engagement with independent experts and a community remediation working group, Barwon Water this week submitted to Southern Rural Water a revised scope of works for its Boundary Creek and Big Swamp remediation plan.

Preparing a scope of works is a critical step in the process required under the conditions of a Section 78 Ministerial Notice that was issued to Barwon Water in 2018, directing it to develop and implement a remediation plan for or Boundary Creek, Big Swamp and surrounding environments.

In accordance with that notice, Barwon Water submitted its scope of works to Southern Rural Water on December 20, 2018.

This document outlined the area that will be covered by the remediation plan, the environmental values to be included and the necessary environmental assessments and methodology proposed to develop the remediation plan.

Barwon Water subsequently sought additional feedback from Southern Rural Water and its Technical Review Panel, as well as the Boundary Creek and Big Swamp Remediation community working group and its independent experts on the scope of works document.

In addition, a comprehensive field program of scientific and environmental assessments to address information gaps was completed during March to June, these assessments included:

• soil sampling (more than 200kg of soil was collected for analysis)
• updated LIDAR imagery to more accurately map vegetation
• installation of monitoring equipment in Big Swamp

Barwon Water concluded its community information session series last night in Colac.

Three community information sessions were hosted over the last week to provide an update on the Barwon Downs borefield licence application withdrawal and the Boundary Creek and Big Swamp remediation project.

Sessions were hosted in Winchelsea, Birregurra and Colac which saw more than 40 people attend. Attendees included representatives from local landcare groups, local land owners, environmental groups and local newspapers.

Barwon Water General Manager Strategy, Systems and Environment Kate Sullivan said the response to the community information sessions shows the community’s passion and dedication for the local environment.

“One of the key themes discussed at information sessions, was the process for developing the remediation plan, which includes prioritising remediation for Boundary Creek and Big Swamp where we know we have had an impact as well as investigating whether there have been impacts in other areas.”

“In addition, attendees were very interested in Barwon Water’s plans to secure future water supplies.”

“Overall the community were positive that Barwon Water were out and about in the community talking about the remediation project.”

The current phase of the remediation project is our environmental assessment field program which is commencing next week, subject to approvals and weather.

“We will provide monthly updates to the remediation working group and meet with the group again in the coming months to provide an update on the field program and what the preliminary results are telling us.”

In the latter part of 2019, Barwon Water will continue to work with the remediation working group and their nominated experts to develop a remediation plan, which will be submitted to Southern Rural Water and its independent technical review panel for approval.

The remediation working group comprises community members and representatives from local agencies and environmental groups, including Traditional Owners, Boundary Creek landowners, LAWROC (Land and Water Resources Otway Catchment), PALM (People for a Living Moorabool), the Upper Barwon Landcare Network, Colac Otway Shire Council and the Corangamite Catchment Management Authority.

Barwon Water is hosting three community information sessions to provide an update on the Barwon Downs borefield licence application withdrawal and the Boundary Creek and Big Swamp remediation project.

An open house style event, the information sessions will be an opportunity for stakeholders and the community to drop in to learn more about both topics. Information sessions will be hosted at the following locations:

Winchelsea information session
Where: The Eastern Hub (Members Room), Eastern Reserve, Hopkins Street, Winchelsea
When: Thursday 4 April from 4pm - 7pm

Birregurra information session
Where: Birregurra Hall (The Seniors Room), 42-44 Main Street, Birregurra
When: Saturday 6 April from 10am - 1pm

Colac information session
Where: Colac Bowling Club, corner of Moore and Armstrong streets, Colac
When: Wednesday 10 April from 4pm - 7pm

The information sessions will provide key information on both the remediation project and recent licence application withdrawal and members of the project team will be available to discuss any questions.