The three sewer districts that were out of commission were the St. Francis, the North Dayton, and the Riverdale low line. The St. Francis sewer is a gravity line, and a manhole at the lower end was completely choked up. It was necessary finally to dynamite this manhole in order to open the line. The two latter lines are both low, and sewage has to be pumped into the river by pneumatic ejectors. The air lines from the compressor plant in the water works pumping station were laid in the levees which were washed out and at one point about 200 feet of pipe was lost. This was difficult to repair, and these districts had to be left without sewerage until April 2, when a by-pass on each line into the storm drains was opened, and the backed-up sewage lowered sufficiently to clear most of the cellars and to permit the use of water closets. While this work was proceeding the organizations devoting their energies to control of infectious disease, inspection, and administration had been far from idle. The State Board of Health had three sanitary engineers and two physicians, trained in public health work, in the city before the waters receded. The city Board of Health was one of the first in the field, and the medical corps of the Ohio National Guard promptly took up the work. Co-operating with one another, under the direction of Major L. T. Rhoades of the United States medical corps, who was appointed chief sanitary officer, and with the assistance of local doctors and nurses and those furnished by the Red Cross, these organizations soon established control of the entire city in a comprehensive and effective manner. The Ohio State Board of Health engineers were assigned to assist in the water works, sewerage, and general cleaning up. Then, in co-operation with the city board and Major Rhoades, the city was divided into sixteen sanitary districts, with a physician in charge of each. These physicians inspected their districts, reported to headquarters, conditions requiring particular attention, instructed people in sanitation and followed up all reported cases of illness to guard against contagion. The city bacteriologist reestablished his laboratory, which had been inundated, and took up diagnostic and analytical work. The state plumbing inspector and the state inspector of workshops and factories established offices, and joined with the city inspectors in pushing inspection work rapidly. Men were sent out to trace all contagious cases that were on the books at the time of the floods, and the reporting of infectious diseases and deaths were resumed as rapidly as possible. Four contagious disease wards were established in addition to the tuberculosis and small-pox hospitals, two in the St. Elizabeth and Miami Valley Hospitals in the city and one each in North Dayton and Riverdale. As fast as infectious cases were reported or discovered, they were removed to one of these wards, and the houses placarded and disinfected.