Wilson, NC 27894 Box 10 P.O. Reclamation Facility Water City of Wilson Wastewater Collection and Treatment System Report System CollectionTreatment and Wastewater City of Wilson Fiscal Year 2018-2019 Year Fiscal The Issues of Inflow and Infiltration Inflow and infiltration (I/I) are terms describing ways that stormwater runoff and groundwater make their way into wastewater collection pipes and eventually get treated, un- necessarily, at wastewater treatment plants. Roof Drain Connection Uncapped Cleanout Inflow is when clear water enters the wastewater system (Inflow) (Inflow) Root Intrusion into Sewer Pipe through rain leaders, sump pumps, or foundation drains that (Infiltration) Storm Cross-Connection are illegally connected to sewer lines. Inflow is greatest during (Inflow) Broken Faulty Lateral major storm events. Sewer Pipe Connection (Infiltration) (Infiltration) Infiltration is when groundwater seeps into cracked or broken Storm Sewer wastewater pipes. Infiltration is a steady contributor to the Faulty Manhole problem, especially when the ground stays saturated due to Cover or Frame Cracked or (Inflow) Broken Pipe (Infiltration) steady rainfall. Infiltration quantities often exhibit seasonal Sanitary Sewer Main Deteriorated Manhole variation in response to groundwater levels. Storm events can (Infiltration) trigger a rise in groundwater levels and increase infiltration flows. The highest infiltration flows are observed follow- What can homeowners do about I/I? How does the City of Wilson minimize I/I? ing significant storm events or following prolonged periods • Familiarize yourself with your house plumbing system. A full time I/I Technician inspects the collection system daily of precipitation. If you have roof downspouts that are piped under- for leaks and other problems. The city utilizes a closed circuit I/I can also be costly to communities. Once clear water gets ground, a sump pump that has no identifiable discharge TV (CCTV) truck that uses a video camera and recording equip- point, or foundation drains that don’t discharge to the ment to document leaky joints, breaks in pipes, etc. The city mixed in with wastewater, it must be treated and that results road side ditch or other low point on the lot, you may be also has a crew that rehabs manholes to eliminate leaks. in additional expenses that can increase rates for all users. contributing to the problem. The City has an ongoing Capital Improvements Program (CIP) Increased inflow during heavy rains can cause problems • Disconnect unlawful connections to the sewer system. planned in 5 and 10-year segments to maintain, replace and Contact Water Resources to help you find reasonable expand segments of the wastewater collection system to Inflow is the biggest problem because during major rain events alternatives. meet increasing demands. it quickly consumes pipe capacity needed for future growth. In • Locate clean-outs on your property and verify that they Collection System Maintenance and Projects completed: more extreme rain events, inflow can cause sewage backups are intact. Broken or loose clean-out caps contribute to into homes and businesses. Inflow and infiltration reduce the inflow. Tighten or replace cap. Contact a plumbing • 49 miles of pipe cleaned (about 14% of the entire ability of sanitary sewer systems and treatment facilities to professional if needed. 359-mile system – 10% required) transport and treat domestic and industrial wastewater. As • Do not open clean-out plugs to drain your yard, or pull • 5,500 feet of pipe replaced a result, wastewater treatment processes can be disrupted manhole covers to drain flooded streets or intersections. • 95 sewer services replaced and may allow poorly treated wastewater to be discharged to Let these areas drain naturally. Contact Water Resources • 26 grease blockages cleared from sewer mains the environment. if you observe abnormal flooding. Wilson, NC 27894 Box 10 P.O. Reclamation Facility Water City of Wilson Wastewater Collection and Treatment System Report System CollectionTreatment and Wastewater City of Wilson Fiscal Year 2018-2019 Year Fiscal The Issues of Inflow and Infiltration Inflow and infiltration (I/I) are terms describing ways that stormwater runoff and groundwater make their way into wastewater collection pipes and eventually get treated, un- necessarily, at wastewater treatment plants. Roof Drain Connection Uncapped Cleanout Inflow is when clear water enters the wastewater system (Inflow) (Inflow) Root Intrusion into Sewer Pipe through rain leaders, sump pumps, or foundation drains that (Infiltration) Storm Cross-Connection are illegally connected to sewer lines. Inflow is greatest during (Inflow) Broken Faulty Lateral major storm events. Sewer Pipe Connection (Infiltration) (Infiltration) Infiltration is when groundwater seeps into cracked or broken Storm Sewer wastewater pipes. Infiltration is a steady contributor to the Faulty Manhole problem, especially when the ground stays saturated due to Cover or Frame Cracked or (Inflow) Broken Pipe (Infiltration) steady rainfall. Infiltration quantities often exhibit seasonal Sanitary Sewer Main Deteriorated Manhole variation in response to groundwater levels. Storm events can (Infiltration) trigger a rise in groundwater levels and increase infiltration flows. The highest infiltration flows are observed follow- What can homeowners do about I/I? How does the City of Wilson minimize I/I? ing significant storm events or following prolonged periods • Familiarize yourself with your house plumbing system. A full time I/I Technician inspects the collection system daily of precipitation. If you have roof downspouts that are piped under- for leaks and other problems. The city utilizes a closed circuit I/I can also be costly to communities. Once clear water gets ground, a sump pump that has no identifiable discharge TV (CCTV) truck that uses a video camera and recording equip- point, or foundation drains that don’t discharge to the ment to document leaky joints, breaks in pipes, etc. The city mixed in with wastewater, it must be treated and that results road side ditch or other low point on the lot, you may be also has a crew that rehabs manholes to eliminate leaks. in additional expenses that can increase rates for all users. contributing to the problem. The City has an ongoing Capital Improvements Program (CIP) Increased inflow during heavy rains can cause problems • Disconnect unlawful connections to the sewer system. planned in 5 and 10-year segments to maintain, replace and Contact Water Resources to help you find reasonable expand segments of the wastewater collection system to Inflow is the biggest problem because during major rain events alternatives. meet increasing demands. it quickly consumes pipe capacity needed for future growth. In • Locate clean-outs on your property and verify that they Collection System Maintenance and Projects completed: more extreme rain events, inflow can cause sewage backups are intact. Broken or loose clean-out caps contribute to into homes and businesses. Inflow and infiltration reduce the inflow. Tighten or replace cap. Contact a plumbing • 49 miles of pipe cleaned (about 14% of the entire ability of sanitary sewer systems and treatment facilities to professional if needed. 359-mile system – 10% required) transport and treat domestic and industrial wastewater. As • Do not open clean-out plugs to drain your yard, or pull • 5,500 feet of pipe replaced a result, wastewater treatment processes can be disrupted manhole covers to drain flooded streets or intersections. • 95 sewer services replaced and may allow poorly treated wastewater to be discharged to Let these areas drain naturally. Contact Water Resources • 26 grease blockages cleared from sewer mains the environment. if you observe abnormal flooding. Our Mission is to “Protect our Environment and Water Quality, through Teamwork and Excellent Service, now and for future generations.” This report provides information concerning the City of Wilson’s wastewater collection and treatment system performance for July 1, 2018 to June 30, 2019 as required in the North Carolina Clean Water Act of 1999 (House Bill 1160). Sanitary Sewer Overflows (SSOs) HOMINY CREEK WATER Once at the WRF, the treatment process begins. The Returning the Water to Nature or Reusing RECLAMATION FACILITY (WRF) treatment plant is designed to treat 14 MGD. The plant the Water Most of this clean water – now called effluent – is dis- currently averages treating 10 MGD. The following de- charged into Contentnea Creek but some of the effluent scribes the treatment process: is sent to the City’s reclaimed water system (beneficial Physical Methods - Primary Treatment reuse) to be used for irrigation or industrial process • Bar Screens – catch and remove large material water and cooling water. (wood, rocks, etc) as they flow past. • Grit Chamber – removes heavy particles that What’s Left Behind Infiltration/inflow (I/I) is unwanted water that enters settle rapidly like gravel, sand, seeds and coffee Now, what about the material that has been removed the sewer collection system through deteriorating old- grounds. As the water enters the chamber, from the water? These solids are called residuals; heavy er pipes, leaking manholes, illegal connections such as gravity causes the grit to settle to the bottom. matter that must be treated in order to safely return to roof drains, etc. During heavy rains pipes can become • Sedimentation (settling) Tanks – as water the environment. flows into the tanks, heavy organic