OR/14/005 Appendix 1 Geological Survey of Tanzania (GST)

Vye-Brown, C, Crummy, J, Smith, K, Mruma,A and Kabelwa H. 2014. Volcanic hazards in Tanzania. Nottingham, UK, British geological Survey. (OR/14/005).

A meeting was held at the offices of the Geological Survey of Tanzania in Dodoma on the 18th October 2013 with Professor Abdul Mruma (GST), Dr Charlotte Vye-Brown (BGS) and Dr Julia Crummy (BGS) to gather information on monitoring and management of volcanic hazards in Tanzania and work alongside GST to conduct fieldwork on the Mt Meru case study.

Aim

To understand current arrangements for the provision of scientific advice and monitoring of volcanic unrest and activity in Tanzania.

The Geological Survey of Tanzania

The Geological Survey of Tanzania (GST) aims to: 'provide high quality and cost effective geoscientific data and information to stakeholders in order to enhance the knowledge and use of earth resources, thereby contributing to national poverty alleviation knowledge of geo-hazards and their mitigation, protection of environment, life and property' and to: 'become one of the leading Customers oriented Geo-scientific Centre of Excellency in Africa in providing national geoscientific data and information by the year 2025.'

The role of GST is to provide geological information, data and advisory services, and to carry out geological hazard assessments. The GST produce, maintain, archive and disseminate national geological data and information. They also conduct environmental studies including mining effects, pollutions and waste disposal, and carry out assessments of geological hazards i.e. earthquakes, volcanoes and landslides, and their risks and mitigations.

GST is part of the Tanzanian Government’s Ministry of Energy and Minerals, and was first declared in December 2004, and inaugurated in June 2005. GST finds a third of its funding through commercial work and is funded by the Ministry of Finance for the remaining two thirds. The GST has 153 employees, of which 56 are geologists, 59 are technicians and 38 are support staff. The geologists train with GST to become specialists in different areas of expertise i.e. seismology. At present there is only one volcanologist in training at GST. The GST collaborate with the University of Dar es Salaam, University of Dodoma and the Nelson Mandela Research Centre in Arusha on research into natural hazards.

Monitoring capacity

Regional seismometers are installed all over Tanzania. Initially there were 5 or 6 non-real-time seismometers installed by Uppsala University. During a campaign to set-up all African countries with base-line seismicity monitoring, African Array installed 12 seismometers and GST received the software to download and process the data. The resources and intent of Africa Array is to provide base-level monitoring of seismicity, but this is not in real-time. Due to increased theft of the original solar panels and seismometers, GST and African Array decided to install the new seismometers in prisons across Tanzania to protect the array. Data are typically downloaded from field locations once a month; however, during the 2007 eruption of Ol Doinyo Lengai, data was downloaded every 3 days.

The GST do have access to real-time remote sensing and satellite data for monitoring through Earth Volcano Observation System Science (EVOSS) and the preparatory Commission for the comprehensive nuclear Test Ban Treaty Organisation (CTBTO).

Eruption management

During an eruption, there is a clear hazard management procedure in Tanzania. GST reports to the government’s Disaster Management Unit (DMU) at the Prime Minister’s Office. The DMU is a committee including Prof. Mruma representing GST, officials from the Commission of Science and Technology, Tanzanian Meteorological Agency (TMA), the police, the Army and other first responders, and other officials representing the government office. The DMU responds to all types of disasters. The Army are the first responders in an event such as a volcanic eruption, and carry out any necessary evacuations.

In mid-2013 the EVOSS monitoring system was delivered to GST. There hasn’t yet been an eruption during which EVOSS could be implemented. Therefore the following is based on eruptions prior to 2013, the last of which was in 2007.

Notification of unrest or an eruption usually occurs as GST receive calls from local people notifying them of tremors and/or ash as there is currently no real-time monitoring of volcanic activity. GST checks the USGS website for earthquakes magnitudes, and then sends geologists to make field observations. If the activity is confirmed, GST notify the DMU. The geologists, often Prof. Mruma himself, make an assessment of the hazard based on field observations i.e. the area covered by ash fall and impact on the livelihood of locals. In Tanzania, this assessment is the Impact Analysis. There are not set protocols for an analysis so that it can be tailored to the circumstance on a case by case basis. This report is presented to the DMU who then assess the level of risk, the danger to local people, and how and when to evacuate if required. During an eruption, where information is available, GST provide daily updates to the DMU, based on a combination of observations of the eruption by GST scientists and the public. The DMU are responsible for passing on official information to the media. Through the DMU, GST inform the public, using local meetings and the media.

During an eruption GST becomes focussed on enabling a response; however, there are limited resources available to support this activity. GST are responsible for contacting various authorities including the local district and regional government and Civil Aviation Authority (CAA). Prof. Mruma advises the CAA in Dar Es Salaam, on the level of activity, character of the eruption, and the area of impact at ground level. The CAA are the central hub for further information to the Tanzanian regional airports etc. The CAA restricts airspace, which in the past has resulted in flights being re-routed slightly, and tourist charter flights cancelled (i.e. 2007 eruption of Ol Doinyo Lengai). The GST has never had any contact with the Volcanic Ash Advisory Centre (VAAC), which for Africa is the Toulouse VAAC. GST also interacts with the Tanzanian Meteorological Agency to share information.

2007 Ol Doinyo Lengai eruption: a case study

The eruption was reported by the local authority who informed GST. In response, GST sent geologists to make physical observations in the field and a seismometer was relocated from Arusha to a location closer to Ol Doinyo Lengai. The GST started monitoring the activity and communicated the hazard to the DMU. During the early part of the eruption data from the seismometer was downloaded every day and latter data was downloaded every three days.

As the event continued, Prof. Mruma was made the director of the DMU. Prof. Mruma made an impact assessment and recommended the relocation of three villages while the eruption continued. These villages were to the west of Ol Doinyo Lengai, in the direction of prevailing wind. The DMU advised the local authority to close access to Ol Doinyo Lengai; however, it is known that some people still climbed the active volcano. One injury is known as a visitor stepped on the cooled crust of a lava flow which gave way to the molten core and resulted in a leg amputation. There are no rescue measures in place on Ol Doinyo Lengai. The DMU have since recommended that access be restricted and emergency facilities including gas detectors and face masks be provided at the summit in close proximity to the overnight camp locations for visitors. These recommendations have not yet been agreed.

During the eruption, the United States Geological Survey (USGS) sent scientists to work with GST on Ol Doinyo Lengai. USGS produced a detailed geological map and took samples for research purposes but results from these could not be processed in time to support the eruption response.

The eruption is reported to have had a big impact on tourism. Many chartered flights to Ngorongoro crater were cancelled due to ash, and safaris were stopped. The eruption also had an impact on the environment with reports of deaths of many flamingos due to the proximity of Lake Ngorongoro which is a breeding ground.

Health impacts from the eruption were revealed by medical assessments attributing the death of many cattle from inhaling ash, and many local people reported difficulty breathing and itchy skin. Cattle were moved away from the areas affected by ash and returned when the ash had washed away and new shoots could grow from 2009 onward.

Recommendations and summary

GST is not run operationally 24/7 and is not currently mandated to monitor or respond to natural hazards. At the present time there is one seismologist on the staff at GST and one volcanologist in training. An eruption puts strain on the resources and trained staff are not always available to respond. However, Tanzania is in need of a dedicated operational monitoring agency to handle geophysical hazards and GST could be well positioned to provide such a service if supported by resource investment and capacity development.

To reduce disaster risk, early-warning systems are needed in Tanzania. Real-time monitoring is sought including seismometers, gas detectors (CO₂ and SO₂) and thermal imaging. GST have the essential infrastructure in place for real-time data collection i.e. broadband internet connection and a back-up generator in case of power cuts.

GST particularly seek to increase their capacity to monitor unrest and forecast eruptions to provide early warning and improve hazard management. In order to deliver this it is known that further work is required on eruption history and magmatic processes of volcanoes in Tanzania to calculate eruption recurrence rates, frequency and cyclicity. At the moment, there are too few detailed studies of historical activity to enable this. GST is keen to work with international collaborators to facilitate this and to compile a database in country of the emerging research results. GST do not have access to journal publications in restricted-access journals; therefore, dissemination of information from international research is essential to increase awareness of impacts of natural hazards.