Grant District Council is continuing to engage with the Local Government Association to investigate the feasibility of the Glenelg River Shacks Community Wastewater Management Scheme Project.


Environmental Health and Regulatory Services manager Aaron Price provided an update on the project at council’s October monthly meeting.


In his report, Mr Price said updated design and costings have been prepared to guide consideration on the feasibility for the project.


“In recent months HDS Australia has refined its initial concept plan looking at a pressurised system,” he said.


“In short, each shack would have a point of containment, being a pump sump.”


The report also provided an update on the meeting of the Glenelg River Shacks Wastewater Project Group and to also seek support for the next steps of the project.


“The Glenelg River Shacks Wastewater Project Group met on in September to review the latest concept design work performed by HDS Australia on CWMS connections for the Donovans, Reed Bed and Dry Creek locations,” Mr Price said.


The Department for Environment and Water (DEW), Environment Protection Authority (EPA) and SA Health were also present at the meeting.


“Complexities associated with potential installations were covered, as well as navigating the next steps,” Mr Price said.


“Since the initial concept design additional land title information pertaining to the DEW leases was provided along with further input from council staff.”


Initial concept designs for Donovans and Reed Bed shacks were developed in May 2022.


A design for a wastewater system servicing the shacks at Dry Creek was also sought from HDS Australia, with revised designs provided to council in July this year.


“The provision of shack connections for Donovans and Reed Bed would involve an extension of the existing Donovans CWMS,” Mr Price said.


“A standalone system at Dry Creek is proposed, consisting of a pressure sewer unit at each property with a common pressure main transferring the wastewater to a commercial septic tank sized to service all eight shacks.


“A holding tank is proposed at a location adjacent to the existing toilet block, which would need to be regularly pumped out.”


HDS Australia had undertaken a condition and capacity assessment of the existing Donovans CWMS.


“The total of 38 additional shacks at Donovans Landing and Reed Bed is slightly above the spare capacity in the Donovans CWMS,” Mr Price said.


“It is expected the existing rising main lines and other infrastructure in the township will not need to be upgraded, but Donovans may need to be replaced with higher capacity pumps to facilitate the higher flow.”


However, Mr Price said if only the Donovans Landing shacks are added, upgrade to the main pump station will not be necessary.


He said this is because the additional 27 connections are capable of being serviced by the existing main pump station.


Meanwhile, the addition of Reed Bed and the remaining undeveloped allotments in the township may result in the need for higher capacity pumps in the main pump station.


“Wastewater flow generated by the small number of additional shacks above the remaining capacity in the existing Donovans CWMS is expected to be accommodated within the existing treatment lagoon,” Mr Price said.


“Detailed design checks of the lagoon and irrigation system, based upon the higher inflow, will ensure the available volume allows the minimum detention time (66 days) to continue to be achieved.


“The irrigation system may need to be expanded to accommodate the additional load in the system.


“The pressure sewer connections at the various Glenelg River shack sites would be full sewer ‘blackwater’ connections due to the lack of space and practicality of installing septic tanks for the individual shacks in this location.


“The rest of the township of Donovans is a septic tank effluent disposal scheme.


“Therefore, either a settling basin will need to be constructed at the treatment lagoon site to allow the additional solids from the blackwater to settle out prior to input to the existing facultative lagoon.


“Or a commercial grade septic tank will need to be installed at each shack area to service all shacks in that area.”


Mr Price said a strong preference for keeping the system as a septic tank effluent disposal scheme by installing commercial grade septic tanks was expressed by council staff following the initial report.


“The latter option has been adopted in the updated concept design,” he said.


A commercial septic tank is proposed to be installed next to the existing community pump station at Donovans Landing, and adjacent the proposed new community pump station at Reed Bed.


“A commercial septic tank of approximately 22kL capacity will be required at Donovans Landing, while one of approximately 9kL will be required at Reed Bed,” Mr Price said.


“The physical distance between Dry Creek and the existing Donovans CWMS, combined with the small number of shacks (eight in total), results in direct connection via a rising main to the Donovans CWMS being cost prohibitive and therefore not feasible.


“A proposed alternative, should shack owners and Council wish to pursue servicing of these shacks, is to install a pressure sewer unit at each property.


“A common pressure main would transfer the wastewater to a commercial septic tank sized to service all eight shacks.


“A holding tank is proposed at a location adjacent to the existing toilet block, which would need to be regularly pumped out.”


Mr Price also acknowledged in the HDS documentation the houseboat moorings would need further consideration leading into a detailed design stage.


“We are looking to get support from LGA in terms of funding arrangements,” Mr Price said.


“The Community Wastewater Innovative Fund was approved in 2023 and provides financial assistance for projects that demonstrate benefit for the South Australian Local Government CWMS sector.


“All project applicants must connect with the Local Government Sector to ensure their projects are of strategic relevance to local government CWMS.


“CWMS Management Committee (CMC), whose role is to monitor the activities of the Program and provide advice to the LGA Board of Directors.


“The CMC is aware of the Glenelg River Shacks need for a wastewater solution and have been provided the concept designs for comment.”


Mr Price also reported on unresolved issues.


“It is also important to note the structural integrity, design issues, and the ongoing responsibility associated with the public access pathway and boardwalk at Donovans have not been resolved,” he said.


“CWMS infrastructure would need to pass through and be maintained in this space.


“Ongoing development assessment, planning and building issues, and shack design related challenges and requirements, also remain unclear.”


He said these matters have been raised with DEW.


The final concept of the Glenelg River Shacks CWMS Project was attached to the October meeting agenda which can be viewed by the public online at www.dcgrant.sa.gov.au/council/meetings/ordinary