tropical cyclone plan

case study: 03 Jan 2017

 

As the annual cyclone season approaches we thought it would be of interest to detail the experience of Cyclone Favio (2007) and the action plan in place to deal with the eventuality of the next potentially damaging weather event.

The Vilanculos area and The Sanctuary fall in a region that is known for the climatic extremes. These include tropical cyclones, torrential rains and intermittent droughts. Tropical cyclones occur on average 3.1 times per annum in the Mozambique Channel. A total of 12 high intensity and 38 medium intensity cyclones have been documented over the region during the last 50 years. In 2002 a category 2 cyclone, with excessive rainfall, passed over The Sanctuary, and then in 2007 cyclone Favio, a category 4 cyclone, had a devastating impact on the environment, infrastructure and operations. Because of the damage caused by this cyclone, The Sanctuary has developed and implemented a Strategic Plan for managing future cyclones to minimize impact, coordinate relief work and repair damage.

Figure 1. Cyclone patterns around the word (Red dot: The Sanctuary)
Tropical cyclones occur between December and April, with a peak risk period between late January and early March.

The primary factor that will impact The Sanctuary during a cyclone is wind and this will particularly affect developed sites along the seaboard which is more exposed than infrastructure in the interior areas that is protected to a greater extent by the surrounding vegetation which acts as a buffer.

There is a risk of flooding of developed sites built near the high tide water mark or on the beach, but this is a risk that owners take in building in low lying areas. The building design and material used can, however, positively influence the ability of a structure to withstand the onslaught of a cyclone and the resultant flooding.

Vegetation can be severely damaged during a cyclone and this influences food / carrying capacity for free roaming game on the reserve.

In order to mitigate risk before, during and after a cyclone, The Sanctuary has a Cyclone Action Plan (CAP) that is reviewed and updated before every cyclone season.

The Cyclone Action Plan consists of four main steps:

  1. Early Warning: During cyclone season, administrative personnel track tropical cyclone activities daily within the Indian Ocean by using websites of the Joint Typhoon Warning Center (JTWC) at http://www.usno.navy.mil/JTWC/ and Hurricane Zone at http://www.hurricanezone.net. These information centers enable The Sanctuary to obtain forecasts up to a maximum of seven days in advance.

    Figure 2. A typical Cyclone forecast by JTWC, including the name, date, time and category

  2. Early Action: As soon as a cyclone is identified as a possible threat to The Sanctuary, step two is initiated. Usually during this period, there is a 3 day forecast warning issued, subject to change. Proactive precautionary measures are taken by The Sanctuary management team as follows:
    • Inform owners, staff and the community of the impending risk
    • Pump water to fill up water tanks (a full water tank weighs 5,000kg, thus is unlikely to be blown away)
    • Take boats out of the water and store securely
    • Pack away major tools, equipment etc. in strong rooms with concrete roofs
    • Put up special shutters in front of the windows where available
    • Pack away loose items and secure furnishings where possible
    • Purchase and store sufficient food and water (Food Security)
    • Stock diesel, petrol and gas (Vilanculos and suppliers will also be affected)

      Note: It is enormously helpful if owners specify how they would like their site secured in advance of a cyclone and cooperate with management to develop a customized plan for their particular residence.

  3. High Alert: This is a warning issued 24 to 36 hours in advance. The following emergency actions are taken:
    • Communicate with owners and community
    • Cover engines where possible with tarpaulins
    • Switch off and close all generators
    • Pack all small items into rooms with concrete roofs
    • Remove communication antennas, satellite dishes and solar panels
    • Secure loose items that are too big to store in dedicated rooms
    • Charge batteries of cell phones and two way radios
    • Assist staff at developed sites with final preparations

  4. Recovery & Restoration: In the aftermath of a cyclone a reactive approach is adopted
    • Enhance overall security at infrastructure
    • Remove fallen / damaged trees from infrastructure and roads on the reserve
    • Make safe / demolish “high risk” buildings
    • Restore water systems
    • Check wiring is in good order, and electrical systems are safe
    • Put out lucerne / supplement to game if needed
    • Check and, where necessary, repair game fence
    • Visit all residential sites and reassure and give guidance to residential staff
    • Check and, where necessary, restore communication network: update owners – Maintain food security: staff, community and game
    • Replenish stock when possible: diesel, petrol, oil, cement etc.
    • Damage assessment: The Sanctuary, developed sites and community area
    • Commence with insurance claim process
    • Contact building contractor(s) to rebuild / repair: assist owners
    • Contact community to start cutting jecca for roofs
    • Work out leave schedules for personnel to go home / families
    • Contact World Food Program (WFP) and other NGO to assist community
    • In-house repairs of The Sanctuary infrastructure commence
The Sanctuary is ready and prepared for a cyclone as never before. The Cyclone Action Plan lays out a protocol to guide all stakeholders through the prelude as well as the aftermath of a cyclone and many of the lessons learnt from Cyclone Favio have resulted in more robust structures and designs being built at The Sanctuary.