City of Jastrzębie-Zdrój: Monitoring ground surface deformations thanks to satellite services
The city of Jastrzębie-Zdrój is located in the south-west of Poland, near the border with the Czech Republic. It has a population of nearly 90,000 inhabitants over an area of 85 km2, of which 60% are mining areas. There are four major mining plants located in the city. The local economy relies heavily on the coal mining industry.
In the long term, mining activities lower soil surface and cause soil movements. If they not monitored in time, soil displacements can have considerable negative impacts on the environment and on urban areas, damaging buildings and infrastructure.
While mining activities can endanger the environment, they are also vital for the current economy of the city. Hence, the Municipality needed to constantly monitor the consequences of mining on soil and infrastructure, to minimise the risks they entail. To do so, city authorities were looking for a solution that would allow them to acquire objective and independent data on soil movements, while avoiding the costs associated with regular site inspections on the whole city territory.
The satellite solution
The City contracted the Polish company SATIM Satellite Monitoring in September 2015. The company acquires one satellite radar image of the city territory per month. These images are then analysed by SATIM through a software and processed into maps showing soil subsidence with centimeter accuracy. The results are accessible through the Online City Map of Jastrzębie-Zdrój as well as via Web Map Service. Every three months, Satim provides the city with a report on soil displacement.
Satellite imagery allowed city authorities to assess that the soil in some parts of Jastrzębie-Zdrój had moved 30 cm between September 2015 and February 2016. To be able to monitor soil deformations entails a number of public and social benefits for the city. Indeed, the city authorities are now able to monitor soil movements with centimeter resolution, to inform the population, prioritise interventions, and to ask for accountability from the mining companies responsible for soil changes.
“The satellite-based deformation map allows us to monitor the risks associated with soil movements over the whole city, hence minimising risks for the population and the environment”, Jacek Kmita, Jastrzębie-Zdrój City Office.