The City of Franklin, Indiana

Clear Water Reduction Program

The City of Franklin is currently working to reduce the amount of excess water that flows into the sanitary sewer system from groundwater and stormwater sources. This excess water enters the sanitary sewers through holes, cracks, and joint failures (infiltration), or via roof drain downspout connections, foundation drains, sump pumps, and storm drain cross-connections (inflow). This water is not meant to be in the sanitary sewer system, as it comes from “clear” or “clean” sources of water. This Clear Water may also be called inflow and infiltration or I & I.

  

Infiltration Example – a crack in the sanitary sewer pipe allowing groundwater into the system (picture provided by City of Oregon, OH).	Inflow Example – improper downspout connection to sanitary sewer (picture provided by Milwaukee Metropolitan Sewage District).

   

What is the Difference Between the Sanitary Sewer and Storm Sewer Systems?

The storm sewer system consists of catch basins, inlets, and conveyance pipes that collect and transfer stormwater from rainfall and snow melt from streets, yards, buildings, and parking lots and then discharges it to local streams and rivers.  Sanitary sewers collect wastewater from toilets, sinks, and washing machines through a property owner’s sanitary sewer lateral. A sanitary sewer lateral is the underground pipe that connects a residence or business to the City’s sanitary sewer line. The sanitary sewer transports wastewater to the wastewater treatment facility where it is treated to remove pollutants before being returned to the environment.

Sanitary Sewer Manhole	Stormwater Inlet

                        

Impacts of Clear Water in the Sanitary Sewer System

Sanitary sewer systems are designed to handle sanitary flows. Excess flows from improper connections, infiltration, or inflow of groundwater to the sanitary sewer system reduces the capacity of the sewer and can overload it. The cost of infiltration and inflow from Clear Water sources, when not corrected, impacts the public directly. Communities should be concerned about Clear Water because it:

• Causes back-ups of sewers into streets and private properties which requires costly repairs and cleanup.
• Causes sanitary sewer overflows (SSOs) that can result in a release of untreated wastewater into waterbodies, directly impacting public health, aquatic life, and ecosystems.
• Increases operation and treatment costs for the collections system and wastewater treatment plant to essentially clean Clear Water which incurs greater costs towards energy, maintenance, and repairs.
• Leads to the installation of larger pipes and wastewater treatment systems, which result in expensive capital projects.

City Activities:

To reduce the amount of excess water entering the system, the sources need to be identified. Identification of the issues will allow the City to develop a plan to fix the problem areas. At this time, Franklin Department of Public Works (DPW) has completed, or is in the process of completing, the following:

• Manhole rehabilitation to remove Clear Water sources.
• Coordination with customers to remove Clear Water sources.
• Conducting smoke testing, a method used to discover improper connections. Non-toxic smoke is injected into the sewer line and emerges from Clear Water sources to the sanitary sewer system that can be identified for correction.
• Conducting manhole inspections, a method used to identify and record inflow from defective manhole covers, structures and joints through visual inspection.
• Sewer televising where remotely guided cameras televise sewer lines to identify Clear Water sources, roots, and structural issues in the pipes.
• Cured-in-place-pipe (CIPP) lining of pipes. CIPP is a method used to repair existing pipes without having to perform excavation.

What Do I Need to Do as a Homeowner or Business Owner?

The City is currently performing public education on inflow and infiltration and improper connections of Clear Water sources to the sanitary sewer. The City is requesting customers evaluate their property for improper Clear Water connections and disconnect them if possible. Typically, the most common improper connections are found at a property owner’s sanitary sewer lateral. Disconnecting downspouts is usually easy.  Refer to the instructional videos below on how to disconnect a downspout or how to connect a rain barrel to a downspout.

 

 

Why Do I Need to Do This?

Per the City of Franklin’s Sewer Use Ordinance, discharges of Clear Water through improper connections to the sanitary sewer are not allowed. These connections decrease sanitary sewer capacity and could lead to increases in utility fees and treatment costs. As a reminder, the operation and maintenance of a sewer lateral is the responsibility of the property owner 

 

ADDITIONAL INFORMATION

City of Franklin – Clear Water Reduction Program Brochure

City of Franklin – Clear Water Reduction Program Brief

USEPA – Combined Sewer Overflow Technology Fact Sheet

EDUCATIONAL VIDEOS

Private Property Inflow and Infiltration - YouTube

Toronto Downspout Disconnect Instructional Video - Bing video

Rain Barrel Installation - Bing video