By Edmund Smith-Asante & Naa Lamiley Bentil, ACCRA
|The Mudor Administration Block|
Plans to decommission the infamous lavender hill are far advanced with about 85 per cent of work on the Mudor waste treatment plant completed.
The lavender hill where raw fecal waste is dumped into the sea in Accra by between 200 and 240 cesspit emptiers daily has gained notoriety worldwide for the unhygienic dumping of liquid waste.
However, numerous pledges by city authorities, the Accra Metropolitan Assembly (AMA) to shut down the broken down waste disposal site as a result of public outcry as well as a court order have not been fulfilled, because Accra does not have any other facility to receive waste from households and establishments.
During a tour of the new waste treatment facility adjacent the famed lavender hill being constructed by the Nanjing Wonders Environmental Protection Company Limited (NWEPCL), a Chinese construction firm for Sewerage Systems Ghana Limited (SSGL) through a public private partnership (PPP), the Project Manager, Ing. (Mrs) Florence Cobbold said the primary aim of the project was to decommission the broken down lavender hill waste disposal site and to give Ghanaians a more decent and environmentally acceptable standard.
|Mrs Florence Cobbold, Mudor Plant Manager explaining a point.|
The project which begun on September 9, 2014, was originally scheduled for completion in August 2016, but Ing. Cobbold explained that the delay in completion had been caused by the importation and clearing of materials required for construction at the port.
“The contractor has asked for an extension to October. The commissioning process can take a while because we need to start the process by charging the system with materials such as cow dung. In the biological process microbes have to be cultivated to feed on the microorganism in the septage to break them down,” she said.
She was however, optimistic that with only about 15 per cent of work remaining to be done the October deadline would be met for the construction works and installation so that the system is charged for the plant to start running by the end of the year.
The Mudor Plant
|A section of the Mudor plant|
The Mudor treatment plant occupies a land area of 7.5 acres and comprises a block of offices which also houses a well-equipped laboratory, Grid Screening machines, a 5,500m3 storage tank, a machine for odor control, and an Upflow Anaerobic Sludge Blanket (UASB) comprising four tanks with capacities of 1,700m3 each where biological treatment will take place.
Ing (Mrs) Cobbold explained that biogas which comprises of methane, carbon dioxide and hydrogen sulphide would be extracted from the UASB treatment process, after which it would be cleaned for methane to generate electricity mainly to run the plant but would give out any surplus to the national grid.
The gas will be cleaned in the three off-white desulphurisation tanks and the expected volume of gas to be generated is about 7,000m3 of gas which is expected to produce between 400kw to 500kw of electricity when the treatment plants starts operation.
The effluent from the treatment process would also pass through an ultraviolet (UV) system before storage in two huge concrete clear water tanks that would hold the treated water that would be released into the sea or lagoon after it has been certified as meeting acceptable standards.
Officials at the site indicated that the globally accepted level of Biological Oxygen Demand (BOD) in waste water is below 50mg/l, while for Chemical Oxygen Demand (COD) it is supposed to be below 120mg/l but said the BOD in the Korle Lagoon was over 3265mg/l due to excessive pollution.
“When BOD is too high it indicates that dissolve oxygen (DO) is being consumed by bacterial present in the wastewater. This is an indicator of polluted water making it harmful to the environment. It means it cannot support plant life or be used for irrigation. The situation also reduces oxygen in the water and kills other living organisms in the water,” he said.
Project cost and benefits
The estimated cost of the Mudor Waste Treatment Plant is US$35 million and much of the cost was taken up by the construction of piles (underground concrete pillars) needed to give the structures a solid foundation because the entire site is a reclaimed land.
A Senior Project Officer of the plant, Mr Julius Kweku Masley said six months was used for the pile work with each of the 3,400 piles taking up as much as 16 bags of cement and therefore, totaling 54,400 bags of cement for the entire pile work.
Mr Masley said the piles were placed at an average depth of 10 metres.
About 70 people would be engaged to run the plant.
Aside that the over 200 cesspit emptiers would be able to hygienically dispose of their waste at the plant at any time of the day since it would operate a 24-hour system once completed.
However, the emptiers would continue to pay their fees to the AMA as is being done already but the MLGRD would in turn pay the operators of the waste facility on a monthly basis.
An added benefit of the waste plant, which would be explored is the production of compost for organic fertiliser or the use of the treated waste water for irrigation, car washing and aquaculture if the right systems are put in place.
ESPA happy with project
The Executive Secretary to the Environmental Service Providers Association (ESPA), Ms Ama Ofori-Antwi commended the government and Sewage Systems for the intervention.
“For a long time, residents and motorists in and around the Lavender Hill have had to endure such foul stench from this site. It is good news that work is progressing, and hopefully, would be completed this month for our liquid waste members to have a decent place to dump the liquid waste”.
Between 200 to 240 cesspit trucks empty their bellies into the Atlantic Ocean at Korle Gonno daily with liquid waste dislodged from homes from all over the Greater Accra Region.
This story was first published by the Daily Graphic on Wednesday, October 12, 2016