Disaster Management Strategies
A Look at Disaster Management Strategies for Chemical Process Industries
Decoding Disasters and Disaster Risk Management
A disaster is a catastrophe, mishap, calamity or grave occurrence in any area, arising from natural or man-made causes, or by accident or negligence, which results in a substantial loss of life or human suffering or damage to, and destruction of, property, or damage to, or degradation of, the environment.
An event is only categorised as a disaster when its nature or magnitude is beyond the coping capacity of the community of the affected area. A disaster is the result produced from the combination of a hazard, vulnerability and insufficient capacity or measures to reduce the potential chances of risk.
Simply put, disasters occur only when hazards and vulnerability meet.
Case Study: Averting a Naturemade Catastrophe
The chemical plant described here is located on the bank of River Tapi, at a distance of about 15 km from Surat city. The plant is located within the fertiliser complex. It handles large quantities of ammonia, synthesis gas and potassium amide at very high pressures and temperatures. The plant also has in its inventory, small quantities of hazardous materials such as hexane, potassium metal, natural gas/naphtha and various industrial chemicals. Some of the chemicals such as potassium amide and potassium metal react violently when they come in contact with water. The river Tapi originates from Betul in the Satpura Hills of Madhya Pradesh, and flows through Maharashtra and Gujarat. A dam was constructed at Ukai, which is 80 km upstream of the Surat–Hazira industrial belt, with the sole aim of avoiding flooding. It has been noticed that the water-carrying capacity of the Tapi river has reduced considerably over the years; the reason is the continuous deposition of topsoil and sewage. The frequency of floods in Surat city has increased due to the reduced water discharge capacity of the river (upto 5 lakh cu secs).
On August 7, 2006, the neighbouring villages and the Hazira industrial belt were faced with the likelihood of a flooding disaster on account of the release of large quantities of water from the Ukai dam. The release of water continued until the plant and the neighbouring villages remained submerged in 5 to 6 feet of water, for four days. The basis flood level that was considered during the plant design was based on historical data of the highest flood level—around 1 ft. However, this figure only reflected the highest flood level the plant had experienced to date.
The plant personnel had received notification about an impending huge release of water from the Ukai dam into the Tapi river in the morning of the day of the incident, and communication had been established between the plant, district collector office and Ukai dam authorities. Based on the information received by the Ukai dam authorities about the release of water from the dam, the decision to stop the operations of the plant was taken to keep water from entering the plant premises. However, at 11:20 pm, the plant tripped due to electrical supply failure (due to the ingress of floodwater into the substation).
The Shutdown Activities Were Completed by Midnight
The shutdown activities were completed by midnight. At 01:30 am, a shift engineer observed that floodwater had entered into plant area through the storm water drains. Officials were also informed that water would enter the residential colony, which was at a 7-ft elevation, by the afternoon of August 8, 2009. By the next day, the water level in the plant premises was significantly high and remained that way for the next three days, owing to the continuous discharge of water from the dam at a rate greater than 11 cu secs for the next three days. The communication system, including mobile phones, failed totally. The plant personnel were stranded at their respective places in the plant, as there was no facility to move through the floodwater. There was absolutely no communication, both within the plant and outside.