Haggard underwent angioplasty in 1995 to unblock clogged arteries. Large scale flooding occurred due to the heavy rain and clogged sewers. These provide positive drainage points that are almost never clogged by debris. The drainage system was also clogged at several places. The majority of problems with the valve system occur due to clogged valves. The ash contaminated oil systems and clogged air filters, and scratched moving surfaces. Roads and highways within and exiting the city are frequently clogged with traffic. Bradley is put into a horrible cell, where the toilet is clogged with feces. Stroke happens when a blood vessel feeding the brain gets clogged or bursts. The roads out of the city were clogged with evacuees. The narrow streets of the old city can become clogged with traffic. The roads are clogged with Arab refugees. Communications were poor and thousands of civilian refugees clogged the roads. Roads were clogged for seven hours. All five bridges spanning the Danube were clogged with traffic, evacuating troops and civilians.