UPDATE ON THE OUTENIQUA WASTEWATER TREATMENT WORKS UPGRADE
Executive Mayor, Leon Van Wyk last week together with Portfolio Cllr Civil Engineering Services: Capital Projects and BFI, Jackie Von Brandis and Portfolio Cllr Civil Engineering Services: Operating Aspects, Browen Johnson visited the Outeniqua Wastewater Treatment Works site to view the status of the current upgrade and review the changes that have been implemented to reduce the unfortunate odours experienced recently.
Ald Van Wyk noted that it was a great pleasure and privilege to visit the old works now back in operation after its refurbishment, looking brand new. “We wish to thank the engineers and construction teams for the work on this entire project over the past few years along with the Municipal teams, senior management, the Municipal Manager and the members of the Mayoral Committee for their management, guidance and oversight. It is also heart-warming to experience the speed of the installation of the solar PV plant that will provide power to the Treatment Works,” he said.
The remedial works on the old carousel reactor has been completed and filling of the reactor started on 04 May 2023. This has reduced the load on the new 10Ml/d reactor since the current inflow to the Wastewater Treatment Plant is between 12 and 16 Ml/d (mega/million litres per day), with 60% to be treated in the old plant and 40% in the new reactor. The situation with unfortunate odours recently experienced in the Pacaltsdorp area will be largely addressed by the re-commissioning of the old carousel reactor. Odour from the inlet works has been mostly eliminated by the new covers over the inlet channels plus the installed odour control system. The odours from the wastewater treatment process will be addressed by the improved aeration treatment capacity.
The three screw pumps from the RAS (Return Activated Sludge) pump station between the settling tanks and the reactors are currently being refurbished and will only be re-installed later in May 2023 when the plant can be operated as per the design intent. In the meantime, some minor imbalance between the two process streams is expected and can prevent the reactors from performing optimally.
The upgrading and capacity extension of the Outeniqua Wastewater Treatment Works (OWWTW) will allow for an increased capacity from 15Ml/dl to 25Ml/d. The total additional number of households benefiting from the proposed wastewater treatment works upgrade is calculated at 19 049. The number of people per household was calculated at an average family size of 4.25 persons estimating the total then at 80 958 persons. The recent development and future growth requirements necessitate the need to increase the capacity of the Outeniqua WWTW. The area to be served by the proposed upgrades to the treatment plant include newly developed and proposed low-cost housing units for the Pacaltsdorp West zone.
The civil works for the 10Ml/day extension were completed in 2019, and the Mechanical-Electrical component of the work commenced in early 2021 after a contractual delay. The full commissioning of the new 10Ml/day extension concludes in June 2023.
Ald Van Wyk, Cllr Von Brandis and Cllr Johnson standing on the refurbished carousel reactor with the newly installed aerators in the background.
While on site Ald Van Wyk, Cllr Von Brandis and Cllr Johnson viewed the progress of the PV installation (400-kilowatt peak kWp) that will be able to power most of the Wastewater Treatment Works electrical loads during the daytime. The system will consist of 736 panels and will occupy an area of approximately 4 800 square metres.