Stormwater Treatment and Reuse

A chicken hatchery in Victoria, was experiencing odour problems emanating from their wastewater treatment lagoons, with pressure from the regulator to address the issue. The site operates two lagoons in series that receive the wastewater generated from cleaning out the chicken hatching sheds. The lagoons operate as facultative systems, i.e. no mechanical equipment is installed to provide mixing and/or aeration. Following years of operating the lagoons without removing any sludge from the system, Lagoon 1 had significant accumulation of settled sludge. This resulted in odours from anaerobic breakdown of settled solids. Solids from Lagoon 1 were carrying over into Lagoon 2, causing the effluent to contain high levels of solids. Effluent from Lagoon 2 is typically irrigated on the property. However, due to prolonged unusually wet conditions at the time, poor effluent quality and odours from the site, irrigation was not possible. The site could not take the lagoons offline to allow for draining, drying and desludging of the lagoons.

Perth’s North Metropolitan TAFE (NMTAFE) offers a Certificate III in Water Industry Operations, as well as education & training for apprentice plumbers. Looking to upgrade the teaching with a real water treatment plant for students to gain hands-on learning, NMTAFE worked closely with MAK Water to procure an industry-built simulator. MAK Water is very proud to have executed on the opportunity to build a training tool for the next generation of Australian water treatment professionals. The plant enables students to gain experience of the scenarios they are likely to encounter in the field after their studies. It also allows trainers and assessors the flexibility to create faults in the systems for the students to diagnose and correct.

An existing service client of MAK Water’s WA service team called to advise a critical plant failure following an extreme weather event in a regional WA town, which left them without wastewater treatment. MAK Water mobilised immediately to assess the damage to the plant and formulate a plan of action. A major element of the storm damage was repairing damage to the PLC and control panel which had suffered a lightning strike. We quickly assessed the situation and formed an action plan to acquire specialised parts and materials to bring the plant back on-line in the shortest timeframe possible. This included choosing and procuring new equipment to repair damaged plant, some re-engineering and customisation of components, organising rapid response influent removal from the site during the repair works, plant reintegration and re-commissioning. MAK Water worked closely with the client and other stakeholders and had the plant back running at full capacity within three weeks.

The Bryn Estyn Water Treatment Plant (BE WTP) is greater Hobart’s primary source of drinking water. It provides approximately. 60% of the water to the seven local government areas of Hobart, Glenorchy, Kingborough, Brighton, Derwent Valley, Southern Midlands, and Sorell. It was originally constructed in 1962, with capacity augmentations completed in 1972 and 1992. Due to the water quality of the Derwent River and the condition of some of the plant infrastructure, the plant’s effectiveness was being impacted. TasWater’s BE WTP upgrade project aims to increase treatment capacity and resilience, enabling the plant to be operated at its original design capacity of 160 ML/d, with expansion capability to meet future water supply demands up to 200 ML/d. This involves constructing new treatment units adjacent to the current plant, retaining existing assets where appropriate. The TasWater Capital Delivery Office (CDO) is responsible for the planning, development, design, construction, and the upcoming commissioning of the BE WTP. The TasWater CDO awarded the granular activated carbon (GAC) supply contract to MAK Water.

A regional wastewater treatment plant was suffering problems with key equipment in their process train. Equipment was either operating inefficiently or was regularly out of service, due to the variability in the quality of onsite washwater. Treated effluent from the plant was discharged into a pond, then pumped into two storage tanks, before being reused for site reticulation and washwater for equipment. Spray nozzles on the inlet screens and on the sludge dewatering equipment were blocking frequently due to solids in the washwater, causing equipment downtime and impacting overall plant operation. The water authority decided to install a filtration system to treat pond effluent before it is stored for reuse. The filtration system had to meet the site’s tight hydraulic and footprint constraints and installation required minimum interruption to normal operations.

A regional council in South East Queensland required replacement of the rotating biological contactors (RBCs) installed at their sewage treatment plant as these had reached the end of their serviceable life. These RBCs were originally designed to treat unscreened settled sewage, but performance had deteriorated over time. MAK Water was selected to provide a mechanical inlet screen to treat raw sewage prior to primary settling, and to provide two RBCs to replace the existing six RBCs within the site’s hydraulic and footprint constraints. This proved to be a cost competitive and fit for purpose approach whilst achieving the plant’s licence conditions.