Threatened With Landslides

• Southern Expressway

By Ashanthi Warunasuriya

Out of all development projects that had taken place recently the Southern Expressway that was constructed at a cost of over US$ 700 million has attracted more attention and discussion than any other. A few days ago, Southern Expressway was in the news again when a section of the highway was faced with a threat of an earth slip. With the bad weather is battering the southern part of the island questions have been raised how a newly constructed highway has fallen to an earth slip threat only a few months after being opened to the public.

Due to constant threats of landslides the area near the 114 km post of the Southern Expressway had to be closed down several times causing immense trouble and hardship to Highway users. The 126 kilometer long Southern Expressway consists of 11 exits, namely Kottawa, Kahathuduwa, Galanigama, Dodangoda, Welipenna, Kurundugaha Hethakma, Badegama, Pinnaduwa, Imaduwa, Kakmaduwa, Godagama, etc. Construction began in 2006 and the initial phase which linked Colombo and Galle was opened in November 2011. Later in March 2014 the section from Galle to Matara was ceremoniously declared open for the public. The Expressway currently reduces the time to travel from Colombo to Galle to just 1 hour from three hours and the 161 km distance from Colombo to Matara to one and a half hours from 4 hours as opposed to the usual ride in the A2 Highway.

The Southern Expressway is now faced with a serious threat of being damaged from landslides. And there are two institutions that are mainly responsible for this threat. They are the Road Development Authority (RDA) and the National Building Research Organisation (NBRO). The Sunday Leader thus contacted two officials in these institutions who were in charge of this project regarding this unexpected threat that has posed a challenge to the smooth operation of the highway. The cause for this landslide has been identified as the soil becoming clay in the area near the 114 km post in Kokmaduwa due to the water being stagnated that had trickled down the slope before the construction of the expressway .

The highway has been constructed by leveling the nearby hills in the area and the process has been observed at two places by the NBRO and both observations have shown that the soil has been unstable due to the stagnation of rain water. Usually when a road is constructed by leveling a hilly area measures such as constructing drainage systems that could drive the water away from the road are taken in order to ensure the stability of the road.

 

Drains blocked

According to the NBRO, similar steps had been taken with regards to the Southern expressway by considering possible future threats. Accordingly the drainage system has been linked to the hill by using the foil nailing system which is suitable for these occasions.  However, with the torrential rains the mud filled water has deposited huge sheets of mud in these drains.

Accordingly the Road Development Authority (RDA) has informed the NBRO regarding this rising threat. Many areas in the country fall victim to landslides due to this reason. Hence the constructions in such areas are done by using the most suitable method, the RDA says. As it further points out in every major construction steps are taken to prevent any possible future danger by properly detecting the effects by using the economy and the technology.  When queried, the Project Director of the Expressway in RDA Opanayake said, “In the construction all the necessary steps were taken to ensure stability. But these kinds of unexpected things could happen during natural disasters. However, upon data received from the investigations conducted, we would take steps to use new techniques in repairing these damaged areas. All in all we have to face all the differences that are made due to weather patterns.”

In this instance the rainwater that had gathered due to heavy rains had remained in a 20-30m wide area and has soaked the land. Hence steps have been taken with the possible threat of landslides to dry out the soil by removing the water trapped inside the soil by using pipes. A joint operation in this regard has been launched by the RDA and NBRO.  Media reports have further shown that officials of both institutions have held lengthy discussion to find out the most suitable method to mitigate this issue. Explaining the proposed solution RDA project director Opanayake said, “We have installed an early warning system in this area. We have discussed this matter with the NBRO and IITA. This signals system gives out a light and a sound in case of a possible hazard. So the RDA, NBRO, AGA, police and all others can be alerted. “

 

Views of NBRO

After the RDA the next main role in the highway construction is vested upon the NBRO.  The Sunday Leader contacted its director R.M.S. Bandara, in charge of landslides to obtain his views on the incident.

“The landslide has been caused by natural causes that have aggravated with the stagnation of water. As soon as we got to know about this we conducted all the necessary observations and experiments to mitigate this issue,” he said. However, he added cost for these reconstructions too has given rise to a question. Having failed to foresee such hazards and constructing the highway accordingly, the Southern Expressway today has faced a tragic loss.

On the other hand, justifying the incident, both the responsible officials in the RDA and the NBRO have claimed that this is a result of a natural disaster and that the necessary technology has been used. Despite justifications, now the highway has incurred another costly reconstruction. When queried regarding the added cost, the NBRO landslide director said, “Still we are going through temporary solutions. We are still holding discussions for a permanent solution. We have not yet prepared any bills for expected expenses. Under short term solutions we are diverting the water away. It is only after that we could take care of the land slide issue.

There could be unexpected losses. However, I do not approve the shutting down of the road due to maintenance. We can never say that the construction of the road was wrong. Everything has two sides. What is necessary is to strengthening these constructions that could withstand natural conditions.”

 

Approval from NBRO

If any construction is made in an area where there is a possible environmental hazard prior approval from the NBRO must be sought. This is a necessity that is equally valid as a law. However, when queried from the NBRO director regarding the failure of Southern Expressway in obtaining such an approval, he said, “During the time of its construction these legal provisions were not in operation. But now it is known to all. At present when RDA is constructing any road it always keeps in touch with us. They always seek our recommendations regarding the area.” It is also said that there was a water spring near the area where the expressway has been constructed. If so, this water spring could even have had an effect on the landslides.

When queried from the RDA and NBRO officials regarding the matter both claimed that they were not sure of such a spring and that they had not seen such a thing during the construction. However, they also confirmed that they had received word from residents in the Kokmaduwa area about a spring. But still they claimed that there was no evidence on it for certain.  However, it is by sheer luck that no one was hurt from this hazard that was created by the adverse weather conditions.

But if the sole reason for such hazards is the weather, then such constructions should not be done without taking such possibilities in to consideration. Even from the comments of the responsible authorities it was confirmed that the constructions have been carried out by preparing for future hazards.

Then where is the problem? This indeed is a mystery. Then the finger is pointed towards the monitoring system that is being carried out after the construction. If the possible danger is known to the RDA, then it is their duty to implement a suitable monitoring procedure. However, when searching for answers, it was revealed to The Sunday Leader from inside sources that the main reason for the failure of proper monitoring and maintenance is the lack of employees.

Nevertheless, it is still the responsibility of superior officials to look in to such problems and to provide solutions. Failing to do their duty is going to cause massive financial losses and more importantly, loss of lives which cannot be measured by money.

At present the repairs are being carried out in the area and the dangerous status has been called off. Both the RDA and the NBRO has informed the public that in case of a danger they would notify the public immediately.