Danube Sinkhole Danube Sinkhole The Danube Sinkhole ( or ) is an incipient underground stream capture in the Upper Danube Nature Park. Between Immendingen and Möhringen and also near Fridingen (Tuttlingen), the water of the Danube sinks into the riverbed in various places. The main sinkhole is next to a field named "Brühl" between Immendingen and Möhringen. The term “sinking” is more accurate than “seeping”, because, instead of just distributing into the soil, the Danube’s water flows through underground caverns to the Aachtopf, where it emerges as the river Radolfzeller Aach. The sinking Danube water disappears into a karst water system of
2007 Guatemala City sinkhole on the city's aging sewerage system, and have speculated that more piping failures are likely to develop unless action is taken. Several rainstorms also contributed to the sinkhole's collapse, as stormwater percolated into the ground, further dissolving the rocks beneath Guatemala City. Citizens of Guatemala City near the sinkhole also reported hearing rumblings a few weeks before its collapse. The INSIVUMEH (Guatemala's seismology institute) had placed a seismic meter there before the disaster; a robotic camera system was supposed to enter the cavity, but the disaster occurred first. On February 23, 2007, the sinkhole collapsed, forming a very large, deep