After heavy rains and widespread flooding swept the area Wednesday, more than 1 million gallons of untreated wastewater into Houston bayous, city officials said. The Department of Public Works and Engineering reported that the sewage, diluted by rain water, escaped from a wastewater treatment facility on the city's east side and flowed into three bayous around the city Wednesday afternoon: Halls Bayou got about 500,000 gallons near U.S.