Four years earlier in 1931, after three years of drought, both the Yangtze and Yellow Rivers experienced significant flooding. Known as the 1931 China Floods, they were considered to be the worst non-pandemic disaster of the century because of the millions of deaths they led to indirectly. With the 1935 floods following on so soon from the 1931 floods, flood relief infrastructure, which included drainage reservoirs and floodwater channels, was soon overwhelmed.