Four alternatives to sewage spout plan on table – BCM

REACTING to an article in yesterday’s paper, “BCM mum on sewage spout plan”, Buffalo City Metro said the marine outfall pipeline is part of a needed upgrade to the sewerage system in the metro’s West Bank as a means of combating the “growing challenges related to the disposal of domestic and industrial effluent” in the area.

Yesterday’s Daily Dispatch reported that environmental concerns had been raised over a proposal to extend a sewerage outflow pipeline 1.4km into the ocean.

Explaining the current position, BCM spokesman Samkelo Ngwenya said: “Historically, raw domestic and industrial effluent was discharged untreated into the sea on both the East and West Banks.

“During the 1980s, a large landbased sewage treatment plant, the East Bank wastewater treatment works (WWTW), was constructed at Nahoon Point. Once this plant was fully commissioned, the marine discharge of untreated effluent from the East Bank ceased.

“However the discharge of untreated effluent from the West Bank continued into the surf-zone at Hood Point. In the mid- to late1990s efforts were made to regularise the situation by investigating the environmental feasibility of both land-based wastewater treatment and marine disposal options to handle these discharges.”

Ngwenya said an environmental impact assessment conducted at the time “indicated that both landbased wastewater treatment and the marine outfall were environmentally acceptable”.

“Based on these studies, BCM opted for a marine discharge of WWTW effluents for which an environmental authorisation was received in early April 2000 from the department of economic affairs, environment and tourism [department of economic development, environmental affairs and tourism]. Additionally, an exemption (1847B) was granted for discharge via a marine outfall in late 1999 by the Department of Water Affairs and Forestry [Department of Water and Sanitation].

“Construction of the West Bank WWTW commenced. However, due to the issues in sourcing funding, the marine outfall section of the works was not implemented.

“Consequently the WWTW was commissioned in 2002, without the outfall pipeline.

“This resulted in the preliminary treated [pre-treated] wastewater effluent being diverted via the emergency overflow pipeline to discharge into the surf-zone at Hood Point. This process was intended to be a temporary measure until funding could be sourced and the marine outfall pipeline constructed and commissioned in order for the pre-treated effluent to be disposed of to the highly dispersive offshore marine environment, as per the original design,” he said.

The cost of this proposed project could run anywhere from around R267-million to R1.4-billion depending on the option chosen.

Ngwenya said that there are four alternatives being considered.

● The current pre-treatment plant operations with effluent being discharged through an offshore marine outfall;

● The current pre-treatment plant operations with the addition of primary treatment, with effluents being discharged through an offshore marine outfall;

● A new WWTW with a nearshore marine outfall at Leaches Bay on the West Bank; and

● The “do nothing option”. “Implementation of the project can only occur after the legislated environmental authorisation process is complete and the competent authority has granted environmental authorisation,” he said.

This pipeline would be a first of its kind in the municipality as “currently there are no deepwater offshore marine outfall pipelines operating in the municipality”.