The Metropolitan Sewer District of Greater Cincinnati (MSDGC) monitors the water quality of major creeks and rivers in Hamilton County, OH, through its wet weather sampling program. During heavy rain events, the sewer system operated by the MSDGC can experience combined sewer overflows (CSO) through the system which are discharged into local bodies of water. The affected bodies of water include Mill Creek, Duck Creek, Little Miami River, Great Miami River, and the Ohio River. These CSOs pose a health and safety concern for humans in contact with contaminated waters during recreational activities such as boating, wading, swimming, and fishing. In response, MSDGC has implemented a program called the CSO Public Notification Program to alert the public in advance when a CSO is likely to occur.
The Columbia City collection system consists of a central core of combined sewer areas surrounded by newer separately sewered areas all flowing to a single WWTP. Columbia City’s sewer system has CSOs to the Blue River and Phillips Ditch at 13 outfalls. The city is required by the Indiana Department of Environmental Management (IDEM) to reduce the volume and frequency of CSOs. Regulatory requirements forbid all SSOs, forbid CSOs for all flows of the 1-Year 1-Hour storm, and mandate storage or treatment for any CSOs of the 10-Year 1-Hour storm.
Hamilton County, OH
Boone, Kenton, Campbell Counties, KY
On August 19th, 2005, the City of Toronto experienced a severe storm that resulted in the flooding of many residents’ homes, erosions in ravines and watercourses, and damage to City infrastructure such as roads, bridges, culverts and sewers. During this storm event, the City received over 4,200 reported basement flooding complaints, the majority of which occurred north of Highway 401. Subsequent severe flooding events occurred in 2012 in East York and in Etobicoke and the downtown core in 2013. The City has identified 36 flooding areas ranging in size from approximately 20 ha to over 1,850 ha in size. XCG was retained to conduct Class Environmental Assessment studies to address basement flooding in Areas 4, 5 and 6.
XCG has been retained to conduct Class Environmental Assessment studies to address basement flooding in Areas 1 and 2. The approach to these basement flooding areas was different from previous basement flooding assignments completed by XCG because City staff prepared the Infoworks model for Areas 1 and 2.
The Regional Municipality of York undertook an Infiltration/Inflow (I/I) Study in the York Durham Sewerage System (YDSS) as a first step towards reducing I/I into their trunk sewer system. The project taken to identify and quantify I/I from major sewers contributing flow to the YDSS and ultimately to develop a strategic plan to address I/I. The study recognized that many of the I/I sources would be located within the local lower tier municipal system and on private property. The objective of the study was to identify specific sources, estimate the costs of removing the source and estimating the reduction in flow that could be achieved. All of this information was used to develop an Implementation Plan.