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Colombo's piling on the dirt
Hiranthi Fernando reports on the deplorable state of Colombo's sewer system
How much longer can the city's sewerage system, now in a shocking state of disrepair continue to function? This is the worrying question plaguing city maintenance officials.

Storm water outlets bringing in sewage and waste water into the lake.

A Sunday Times investigation revealed that numerous unauthorised constructions and illegal connections discharging waste water and sewage into the storm water system are playing havoc with the smooth functioning of the city sewer system as well as the storm-water pipe network.

During our survey, we found several manholes with lids broken, fully silted and filled with garbage. Others were inaccessible, buried under the road surface and under buildings.

Construction has also taken place over storm water drains. Sewerage outlets of some houses have been connected to the storm water pipes, which are only supposed to carry surface rainwater.

A well-planned sewerage system is one of the major infrastructure requirements of a city. During the British period, Colombo was provided with a pipe-borne sewerage system. Underground pipe networks beneath the main road networks were connected to pump houses where the waste was treated and pumped into the sea, half a kilometre from the shore. Manholes at road level provided access to the network for cleaning and maintenance.

"It was a good system, with huge sewer lines, which could still work well despite the greatly increased population, provided regular maintenance is carried out," commented a retired engineer of the Colombo Municipal Council. During his days at the CMC, he explained, there was a simple maintenance programme. They had a map indicating every sewer line, the diametre of pipes, location of manholes and pump houses in relation to the road network.

Every road was handled in turn by different crews, on a regular basis. There were no engineers, but gangs comprising one overseer and several unskilled labourers, opened up the manholes checking for blockages and clearing them.

Since this system of regular monitoring was discontinued in the '70s, sewage began to get solidified inside pipes, the flow slowed down and sedimentation set in, resulting in total blockages. With the lack of maintenance, some parts of the network have broken down and manholes are found to be full of debris.

As a short-term solution to prevent the overflowing of sewage into the streets, some manholes have been connected to the storm water system, which is an entirely separate network.

These storm water drains are connected to the Beira Lake or to the sea as they are meant to only carry rainwater. But now, sewage as well as chemicals and other waste materials flow into the lake and pollute it.

Under Phase 1 of the Beira Lake Restoration Project, a new sewer system was laid around the Beira catchment area. New pumping stations have been built at Slave Island and Vauxhall Street and the existing pumping station at Polwatte has been repaired. A main line was also laid along Duplication Road, from the Polwatte pumping station to the Wellawatte sea outfall. The Water Board is the implementing agent for this project.

Deputy General Manager, Special Projects of the Water Board Mrs. P.R.L. Seneviratne, explained that a survey was carried out to identify sources discharging waste water and sewage directly into the Beira. Lines have been laid to divert these to the Colombo sewerage system.

Work on the South West lake (near Gangaramaya temple) has been almost completed. Here most of the public sector and other organisation outlets polluting the lake have been diverted. The discharge of chemicals by four laundries has been stopped. Over 700 notices have been served to properties, she added.

However, some private properties, homes and factories that have diverted sewer lines to storm water drains have still not been detected.

At D.R. Wijewardene Mawatha too, a new sewer line has been laid. About 10 properties discharging waste into the storm water lines have been identified. These could now be connected to the new sewer line. Work on Phase I of this project has to be completed as soon as the defect liability period of the Chinese contractor ends in June. Mrs. Seneviratne said with proper maintenance of the lines and pump houses the system could work well.

A spokesman for the Waterworks Department of the CMC said they are now in the process of disconnecting waste water and sewage lines from the storm water pipes and diverting them to the newly laid system. Most of the outlets have been identified, he said. "The CMC is also involved in identifying major overflows to prevent flooding of the sewers," the spokesman said. "We are in the process of cleaning the system to avoid overflows. But we have difficulties in tracing and exposing manholes that have got buried in the road. As the Police do not allow us to park our vehicles and excavate during the daytime, we are now working at night."

Six District Officers and six District Engineers are charged with the responsibility of operating and maintaining the sewer system. Removal of unauthorised constructions, which also poses a major problem to the sewer system is handled by another division. The manhole covers, made of cast iron are often stolen and have to be frequently replaced.

Budgetary constraints are also a factor to contend with. Of the annual budget of Rs.90 million for the sewerage system, Rs. 70 million is spent by the CMC and Rs.20 million by the Water Board. However, last year the CMC had to spend Rs. 180 million as the system is old and needs rehabilitation and repair.

The cost of a new sewerage system is prohibitive. Proper maintenance of the existing system therefore is imperative to prevent further breakdown. It needs a concerted effort by the authorities concerned to ensure that a regular programme of maintenance is adhered to and the network kept accessible by the removal of all unauthorised structures that have sprung up over the network. With modern equipment available today, maintenance would not be such a difficult task as in the old days.

Stench of negligence
The elaborate plans for developing the Beira Lake into an attractive recreation spot would be fruitless unless the lake is cleansed of all waste matter. Along the newly constructed walkways bordering the lake, we came across several storm water outlets, which were discharging waste water mixed with sewage into the lake.

At the junction of Rotunda Gardens/Perahera Mawatha, a storm water pipe coming from the Kollupitiya market side is contaminated with waste and sewage. A sewer outlet of a building now occupied by a bank, connected to the storm water pipe was recently detected and notice served on the owner of the building but no action has been taken yet.

At Union Place, the manholes on the sewer line are blocked. The sewer manhole has been connected to the storm water manhole to prevent overflowing and this is again channelled into the Beira.

At Wekande Road, Slave Island housing units have been built over the storm water drains. Although there had been no rain, water was flowing through the storm water drains; obviously from waste water outlets.

Elsewhere, a sewer manhole was found inside the compound of a house. The occupant of the house says no one comes to clean it now.

On the sewer line under Vauxhall Street, all the manholes are buried under the road and cannot be seen or detected. An unauthorised soft drink outlet has been built over one sewer manhole and cemented over due to the stench emanating from it.
Sewage from a row of newly constructed unauthorised shanty dwellings on the Beira reservation area flows directly into the lake.

On the banks of the east lake of the Beira too, a large number of unauthorised shanties built over tyres and planks almost floating on the water add to the pollution. It is estimated that almost 1000 families are living in unauthorised shelters around the Beira lake.

Pathogenic waste from the National Hospital also flows into the Beira through Norris Canal, which goes through Deans Road and Darley Road to the lake. A proposal has been made to install a surface channel interceptor to divert the wastewater to the sewer manhole during the dry season. During the rainy season, the wastewater, diluted with rain water would flow into the lake.

Apart from the Beira area, down 22nd Lane, opposite the Oberoi Hotel, the sewer manhole lay open, full of silt and completely blocked. Several large buildings in the vicinity have their sewer outlets connected legally to this sewer manhole with approval from the authorities. The underground sewer line runs parallel to the railway line. This sewer line is not functioning and to avoid blockage, the concrete sewer pipe has been damaged in at least two spots so that the sewerage flows into the open storm water drain, which flows directly into the sea by the railway line. This sewer line should go to the Wellawatte pumping station to be treated and pumped out into the sea .

The Waterworks Department, responsible for maintaining the sewer system, appeared to be unaware of the broken manhole and the sewage discharged into the sea. On being informed, an officer handling the area was instructed to look into the matter.

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