"Among the most vulnerable coasts will be Depok, Kuwaru and Baru as well as west of it because the houses were built close to the the coasts, chief of the BPBD Dwi Daryanto said here on Sunday.
The houses and business buildings in the southern coast are vulnerable to high tides during the period of high waves as predicted by the the Meteorology, Climatology and Geophysics Agency (BMKG) this week.
Moreover, the high waves will be three to six meters high in the waters off the southern coast of Yogyakarta. The waves are a natural phenomenon which could happen anytime.
"The houses are very close to the coast. In the past they might be far from the coast. But under the current natural condition, the sea water is getting closer to the residence," he said.