The presented diploma thesis is focused on the identification of environmental risk factors in relation to the precipitation-runoff process. The most risky factor in the formation of surface runoff can be considered the forest transport network, which is used primarily for the approximation of timber in connection with logging and restoration activities in forest management. The soil surface is disturbed during the removal of the wood and is also compressed, which causes an accelerated concentrated outflow of water on these roads at the time of precipitation. Intensive mining activities have a major impact on the runoff processes of the river basin. The sudden onset of flood flows during heavy or prolonged rainfall is no longer unusual. The compacted soil on the road surface does not manage to absorb water during heavy rains, which significantly accelerates the surface runoff.In the results of the work, we evaluated the current state of the transport network in the Lodnianka river basin. Through a field survey carried out in the years 2018 - 2020, we mapped all paved and unpaved roads on forest and agricultural land. The actual and optimal density of the transport network was also calculated. We compared the current state found by the field survey with the map of land and forest roads in the Slovak Republic, which was prepared by the National Forestry Center. In the next step, we calculated the surface runoff of water coming from the transport network. Finally, we evaluated the changes in land cover in terms of deforestation for the period 1990 - 2018.