Sunday, May 24, 2015

Romania's Main Natural Hazards Assessment Report



EARTHQUAKES and LANDSLIDES

Main natural hazard: Earthquakes
In terms of seismicity,  Romania is considered to have a moderate seismic activity, given its geographical position and its closeness to a convergent plate boundary. Being situated in a seismic active region, Romania
has a history of devastating and deadly earthquakes. The Bucharest area has experienced a number of earthquakes of varying intensities, and the probability that a severe and damaging earthquake will occur is high. From: http://romania.usembassy.gov/acs/disaster_preparedness.html  In fact, Bucharest, the capital of Romania, has been named by the British paper "The Guardian" as Europe's earthquake capital. (http://www.theguardian.com/cities/2014/mar/25/risky-cities-red-equals-danger-in-bucharest-europes-earthquake-capital). 
Here are three photographs from the 7.2 M on the Richter Scale Earthquake in Bucharest, Romania which resulted in 2000 deaths in 1977.

Earthquake images - Bucharest, Romania, 1977 (1)


Earthquake images - Bucharest, Romania, 1977 (2)








Earthquake images - Bucharest, Romania, 1977 (3)





























Why they happen?
The cause of earthquakes is clearly the geographical location of Romania which is situated close to a convergent plate boundary at the convergence of the East European Plate (EEP), Moesian microplate (MoP), and Intracarpathian microplate (IaP) which seem to meet into the Vrancea area (South-Eastern part of the country), whose active seismicity has been considered to be due to the presence of a continental unstable transform-transform-compression triple-junction. 
From: http://adsabs.harvard.edu/abs/2003EAEJA.....5534B  Thus,
the Vrancea region, located in the South-Eastern part of the country is especially high in earth quakes and traditionally has been the epicenter of many earth quakes.

Recommendations
Earthquakes cannot be prevented, they are naturally occurring phenomena, but they may be predicted/foreseen in order to allow local population to protect themselves or if not at least properly educate people and raise awareness about what they should do in case an earthquake strikes.
Given these tragic events involving devastating loss of human life and after centuries of seismic damaging events, earthquake resistant design codes for buildings were enacted in 1942 as well as provisions to evaluate and rehabilitate existing buildings. A new earthquake design code with a new zoning map began to be enforced in 2004-2005, increasing the demands for rehabilitation of existing buildings.

According to http://www.iitk.ac.in/nicee/wcee/article/13_2023.pdf, the Romanian National Center for Seismic Risk Reduction is involved in:
  • issuance of new technologies for retrofitting the earthquake vulnerable buildings and structures, as well as new codes for seismic resistant design, with a special component for seismic instrumentation of Bucharest and of densely built areas;
  • transfer to specialists state of the art knowledge in the anti-seismic protection domain and issuing documentation regarding the education of the population and knowledge dissemination for preventing risks;
  • development of technical knowledge by training, studies and documentation, seminars, courses and lectures in Romania and abroad, promotion of the international cooperation for seismic risk management, studies and publications in this field of activity
All of the above make for efforts that authorities in Romania are undergoing in order to prevent the horrific catastrophes that happened in 1940 and 1977, respectively.

The latest major earthquake in Romania (M 5.6) occurred on November, 22nd 2014. No victims or significant damage were reported, however the quake was strongly felt in Bucharest and several other parts of the country. See http://www.euronews.com/2014/11/22/earthquake-measuring-56-strikes-romania/

Target areas to help first
The South Eastern part of the country which comprises the Vrancea region, located at a continental unstable transform-transform-compression triple-junction. The South Eastern part of Romania includes big Romanian cities, such as Bucharest, Buzau, Braila, Galati, etc. Given that these areas are most vulnerable, measures have first to be taken here in order to address earthquakes.

Where I would build my house
I would build my house in the Northern, Western and Central parts of Romania. These are areas that have not been affected by many earthquakes. However, risks are posed by the construction of high rise buildings or even 7 floor blocks of flats. With regards to this risk, Romania has taken steps to retrofit the earthquake vulnerable buildings and structures, as well as reissue new codes for seismic resistant design and obey new standards in construction.


LANDSLIDES
Main natural hazard: Landslides
First and foremost, according to an article very suggestively entitled "Why is it so difficult to assess landslides hazard and risk in Romania?" by Romanian renowned geophysicists from the Geological Institute of Romania, Raluca-Mihaela Maftei, Constantina Filipciuc and George Vina, available at http://connection.ebscohost.com/c/articles/85206845/why-so-difficult-assess-landslides-hazard-risk-romania, landslides constitute a very common geomorphic hazard in Romania, mainly in the hilly regions which occupy around 30% of Romania's territory. But these regions are not the only ones to be affected by this geological phenomenon. Mountains too are affected by this and according to http://www.naun.org/multimedia/NAUN/geology/ijgeo-10.pdf, in Romania slopes affected by landslides are located in the Eastern Carpathians.


Landslide in the Carpathian Mountains (1)

Why they happen?
Landslide in the Southern Carpathian Mountains (2)
Unfavorable natural conditions such as: non-uniformity in the slope lithology, high slope gradients, and high rainfall rates combined with engineering works have accelerated local instability by increasing surface runoff and erosion. This has lowered the base level in the adjacent valleys/gullies by 1-2 meters, increasing the slide potential. An example for the eastern part of Romania's Carpathian Mountains is the Zemes landslide, which extends over 1.4 -1.8 kilometers in length, with a width of around 500 meters at the slope base and a total change in elevation of about 350 meters. This and similar slides cover 30-40 percent of the land on both sides of Tazlaul Sarat Valley. They have developed especially on soft or altered rocks. Unfortunately, these recurrent landslides produce an asymmetric shape to the valley, which increases the potential for landslide reactivation because of infiltration of water into the ground.


According to an article on landslide movements in Romania published in the International Journal of Geology in 2007 http://www.naun.org/multimedia/NAUN/geology/ijgeo-10.pdf, most landslides in Romania occur as a result of a combination of: 

          1) poor forest management and  
          2)   intense rainfall.

A study of susceptibility for landslides was carried out in Romania through use of the following methods: historic information concerning landslide occurrence, information about triggering factors, landslides classification, damages caused, field measurements and lab tests undertaken to determine physical properties of rocks, landslides mapping, landslide hazard zonation. Gradually, new methodologies were introduced, such as the Geographical Information System (GIS) for environmental monitoring.

Recommendations

According to http://connection.ebscohost.com/c/articles/85206845/why-so-difficult-assess-landslides-hazard-risk-romaniahttp://connection.ebscohost.com/c/articles/85206845/why-so-difficult-assess-landslides-hazard-risk-romania , given the very common occurrence of landslides, the Geological Institute of Romania worked on landslide inventory maps, risk management and assessment (analyzing and reporting systematic risk factors). However, public access to landslide hazard and risk maps is not facilitated, so people tend to largely be uninformed about the risks in their areas with respect to landslides. Moreover, public administration authorities have not identified, delimited or declared which are the high risk zones in their jurisdictions.
But, at the same time people who live in areas prone to landslides, people (over 80% of participants in the study) were aware of the relations between landslides and other phenomena: rainfalls, slope declivity, torrents, etc. as well as human activity: salt and oil exploitation, construction in areas with risk, closed mines, poor forest management; moreover, 70% of them had been suffering because of the direct impact of landslides.
According to the same above mentioned article published in 2012, people's involvement with local authorities tends to be minimal (they don't have any input for administration's plan with respect to the prevention of landslides), but out of their own willingness, they plant trees, fill up the cracks in their houses with cement and make wooden nets.
But Romania needs to do a lot more in order to prevent landslides from happening. The following expert recommendations were gathered from a report by the European Commission - Institute for the Protection and Security of the Citizen located at http://eusoils.jrc.ec.europa.eu/ESDB_Archive/eusoils_docs/other/eur20558EN.pdf (page 83) which outlines conclusions and key lessons learned in dealing with landslides and lists everything that should be done in order to mitigate landslides in an effective way. Thus, recommendations are as follows:

         1) Total reconstruction of the whole water supply and sewage systems in both actual and potential landslide areas so that underground utilities be watertight.
   2) Building in areas affected by exclusion or restriction regulations should not be allowed and regulations on building restrictions in these areas should not be changed  without the previous implementation of additional underground utility systems.
   3) Stability analysis and risk assessment of steep slopes should be done prior to building up any structure on them. Both the density and the height of the existing building structures on these areas should be taken into consideration The stability of the whole zone should be examined as a result of the construction plans.
   4) Create a cadastre of the populated areas, residential districts, underground and open pit mine sites, railways, highways and other areas that are affected by landslides.
   5) Produce mass scale maps of the landslides affecting populated areas and mass communications.
   6) Produce geotechnical maps of populated areas and important economic sites.
   7) Determination and localization of the most dangerous landslide areas in Romania where landslides would have the highest economic and social impacts.
   8) Ecological ensuring of the anti-landslide structures and equipment.
   9) Creating regional committees and organizations specialized in surveying and monitoring landslide prone areas.
   10) Making the most vulnerable areas and roads safe from landslides.
   11) Organizing and carrying out anti-landslide actions, such as (a) maintenance of communal services and electric supply systems, (b) drainage and afforestation of the threatened areas, (c) suspension of building and blasting works, (d) reducing weight on slopes and applying strengthening measures.
   12) Creating an alarm system and a local radio net system in the most dangerous landslide areas.
   13) Keeping preparedness at a good level for carrying out rescue operations, emergency restoration works and evacuation.
   14) Population training and acquainting with landslide consequences and landslide prevention or mitigation activities

        According to Keller and Blodgett (2008), there are sensible recommendations to be followed. Thus, where landslides occur independently of human activity, we need to avoid development or provide protective measures. In other cases where land use has increased the number and severity of landslides, we need to learn how to minimize their recurrence.
For example, in some cases filling large water reservoirs has altered groundwater conditions along their shores and caused slope failure. Logging operations on weak, unstable slopes have increased landslide erosion. Moreover, grading of slopes for development has created or increased landslide problems in many urbanized areas.  Keller and Blodgett (2008) thus recommend:

       15) Monitoring and mapping techniques which help identify hazardous sites, as identification of potential landslides has been used to establish grading codes and these codes in turn have reduced landslide damage.


       16) Engineering techniques to prevent landslides such as: drainage control, proper grading, construction of supports: retaining walls.

Target areas to help first
The hilly regions of Romania and the mountainous regions of the Carpathians would be the main areas of interest where the above recommendations would need to be implemented first. Having a landslide warning system in these regions, even though it won't prevent any landslides from happening, will provide time to evacuate people and their possessions as well as stop trains or reroute traffic. And these target areas will sure benefit from a landslide warning system.


Where I would build my house
I would build my house in the South Eastern part of Romania which is rather sheltered from landslides, as this is not a hilly region, neither a mountainous one. However, were I to purchase a property situated on a slope, I would have  a geologist inspect property before purchasing and provide me with a landslide hazard assessment. Unfortunately, the South Eastern part of Romania is a region that is exposed to earthquakes. Therefore, it is important to note that no region in the country is exempt from potentially devastating geological phenomena and therefore authorities need to adapt their emergency plan to the specifics and geological and geographical make up of each region.

1 comment:

  1. Fantastic report! You talk about how the public access to information is not really facilitated in some cases...a pity for sure. Sometimes even with that accessibility, we still make wrong decisions.
    I had a look at the population density of Romania and it definitely seems the Western side and South of Bucharest are less populated, therefore, with potential for less catastrophes. I also agree that even in regions of low risk, we all should be aware of potential issues on the land we live on.
    Thank you for teaching us about Romania in so much detail!

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