MBB Consulting Engineers is assisting the Makana Local Municipality, (MLM), in the Eastern Cape Province, by providing professional engineering services for the Upgrade and Refurbishment of the Belmont Wastewater Treatment Works (WWTW), in Makhanda, formerly Grahamstown. The professional services entailed conducting a situation assessment and scoping of the refurbishment and upgrading requirements. MBB also monitors the implementation of the refurbishment works for 12 months.

Makhanda’s sewage system is divided into two distinct drainage areas (North and South), which drain into the Mayfield and Belmont (WWTW) respectively. The Belmont installation treats sewage flows from the commercial, industrial, institutional and residential areas of central Makhanda as well as from the Vukani, Fingo Village, Tantyi and Hlalani residential townships. The treated effluent from Belmont is discharged into the Bloukrans River, a tributary of the Kowie River, which drains into the Indian Ocean, 60km away

Belmont WWTW has a  current design capacity of 5,4 Mℓ/day but the estimated current dry weather inflow into the plant is estimated to be between 8Mℓ/day and 9Mℓ/day, with wet weather inflow estimated at 11,4 Mℓ/day. Several future residential and business developments are expected to add 5,8 Mℓ/day in the medium term, bringing the total flow to 17,2Mℓ/day. This is far beyond what the treatment plant can handle. The situation is worsened by the state of the plant, where almost every component of the treatment works from inlet through to disinfection has deteriorated and is near collapse, rendering the existing plant as simply a flow-through, without even partial treatment taking place. This has resulted in massive pollution in the receiving water bodies. Thus, it is necessary to refurbish the Belmont facility to address the dilapidated and collapsed elements as well as to upgrade the treatment capacity to deal with the increased inflow, to treat the sewage to produce an effluent whose quality complies with the Department of Water and Sanitation discharge standards.

Factors influencing the upgrade are:

• Extreme weather events have damaged the plant, (floods have washed away a couple of maturation ponds).
• Lack of maintenance.
• Inflow that exceeds the design capacity.
• Hydraulic overload which has caused the trickling filter walls to collapse.
• Extensive damages in the inlet works and sludge drying beds.
• The sludge digester is non-functional.

Apart from inspecting and preparing the conditional assessment and detailing the refurbishment scope, MBB undertook a feasibility study for upgrading the treatment works.  A decision was taken to refurbish only the components of the existing plant that will be integrated into the future upgrade of the works.

The current refurbishment scope entails:

• Refurbishment of the inlet works, walkways, handrailing, two primary settling tanks (PST), digester and sludge drying beds. A flow meter and new pumps at the various stations of the treatment process will also be installed.
• Converting the primary settling tank into a sludge thickener.
• Dismantling and reconstruction of two biofilters.
• Installation of a new disinfection plant.

The refurbishment project commenced on the 13^th of April 2023 and is estimated to be completed on the 13^th of April 2024. The contractor is running behind the program but their recovery plan will be monitored very closely to complete the project on time.