Problems of the analysis of nature and technogenic danger and estimation of the territorial risks
connected with large hydraulic engineering constructions are considered. The calculation algorithm
for failure after-effects on hydraulic engineering constructions of the hydroelectric power station
is proposed. It consists of the following steps: development of digital cards based on models of the
estimated area relief, preparation of initial data about adverse process considered, calculations of
break wave parameters, estimation of the flooded areas and objects, and estimation of damage if the
scripts of failures marked out are realized. Examples of hypothetical failures for Krasnoyarsk and
Boguchan HPS are described.