Estonia switches from Baltic Height System to European Vertical Reference System
The Minister of the Environment has approved the necessary amendments to the Regulation on Geodetic System, which enable Estonia, similarly to many other countries in Europe, to start using the Amsterdam Ordnance Datum (Normaal Amsterdams Peil NAP) as the reference level for height measurements. Thus, Estonia is giving up the Kronstadt Tide Gauge that served as zero point of the height system so far.
“Preparations for the change have taken a long time, but in time for its 100th anniversary, Estonia is now finally changing the systems. Transition from the Kronstadt Tide Gauge to the Amsterdam Ordnance Datum means a 15 to 24-centimeter increase of absolute heights depending on the area. For example, Suur-Munamägi, at 317.2 m Estonia’s highest point, will now be 317.4 m above sea level,” explained the Minister of the Environment Siim Kiisler. In nature the height of Suur-Munamägi remains of course the same, neither will change the sizes of water protection zones.
“There have been several reasons for the changeover to the European Vertical Reference System. The Baltic Height System of 1977 has become obsolete, inaccurate physical parameters have been used in its specification, and then there was the wish to be in one and the same system with Europe. These reasons led to the decision to make all necessary preparations for the changeover,” said Tambet Tiits, Director General of the Land Board.
He added that by the year 2000, approximately 47% of the previous levelling benchmarks had been damaged or disappeared, which made levelling both time-consuming and costly. Since then the Land Board has reconstructed the national levelling network that allows now also accurate height determination by GPS.
Most countries in Europe, including Finland, Norway, Sweden, Latvia and Lithuania, already use the vertical datum realized by the zero level through the Normaal Amsterdams Peil (NAP). The introduction of the same reference system in Estonia simplifies the implementation of cross-border construction projects as there will be no need for transformation between different datums.
A three-month transition period has been set for the system switch. All construction projects initiated before the 1st of January 2018 may be executed in the old system.