Two major construction contracts linked to the R5 billion upgrade of Potsdam Wastewater Treatment Works (WWTW) received the go-ahead recently.
These contracts served on the City Council agenda on 29 March to approve a final statutory public participation process before awards to the successful bidders.
This follows the City’s tender appeals authority’s decision to dismiss appeals on both major contracts. Progress is also being made on critical maintenance work to improve treated effluent quality at Potsdam, including major cleaning work to maturation ponds and the re-engineering of natural reed beds to prevent pollution from reaching the Diep River.
Potsdam upgrade
Potsdam WWTW is benefiting from a R5 billion capacity upgrade, from 47 million litres of treated wastewater per day to 100 million litres per day. “Cutting-edge membrane technology is also being added to ensure high wastewater treatment standards,” the City told TygerBurger.
The City adds that with the tender appeals dismissed, all that remains is a 30-day statutory public participation before the contracts can be awarded.
Construction is set to start in May on the Potsdam upgrade if all goes to plan.
“We will monitor this upgrade closely to ensure it stays on track. Multi-billion rand upgrades to Potsdam, the surrounding sewer network, and pump stations are a major step towards restoring the health of Milnerton Lagoon.
“Consultants are also due to complete their study on short-term interventions to improve lagoon water quality and odour, including options to potentially aerate or bio-remediate the lagoon. The City aims to steadily close off pollution sources to the lagoon, building up to the ultimate goal of dredging and removing the sediment at the bottom, along with decades of pollution build-up. We are committed to addressing these challenges in partnership with all who care about restoring the health of the lagoon environment, which is non-negotiable for the City,” says Mayor Geordin Hill-Lewis.
The project
The Potsdam upgrade project is split into two components:
- Mechanical and electrical tender:
This tender is for the design, supply, installation and commissioning of mechanical and electrical infrastructure to upgrade and expand Potsdam WWTW.
- Civil tender:
This tender is for the civil construction of infrastructure and buildings to upgrade and expand Potsdam WWTW, including demolition works.
“A Section 33 Municipal Finance Management Act (MFMA) public participation process is required for projects exceeding three years before entering into a contract with a service provider,” the City says in a recent statement.
Hill-Lewis says the City’s upcoming 2023-’24 Budget proposes R8,6 billion in capital upgrades to wastewater treatment works over three years, alongside R1,4 billion in bulk sewer upgrades to the Milnerton, Cape Flats, Gordon’s Bay and Philippi lines.
Progress in maintenance work
Work is already nearly complete on the re-engineering of natural reed beds adjacent to Potsdam WWTW to prevent polluted stormwater from reaching the Diep River, the City says.
“The reed beds are now better able to retain this stormwater – through raised walls and valve installations. Historically, the reed beds acted as natural filters for pollution in stormwater before it reaches the Diep River. Now the polluted stormwater can be largely retained, and pumped back to Potsdam for treatment.
“Major work to drain and clean maturation ponds at Potsdam is also under way, and is expected to be complete by June. Effluent is meant to be retained in these ponds before release, but pollution build-up in the pond sediment has prevented this. As a result, the ponds are currently being by-passed using pumps as far as possible,” says the City.
Once cleaned, the ponds will be able to retain final effluent, before a final UV treatment of effluent before release into the Diep River. This is set to have a significant positive impact on effluent quality.
