The need to reduce the flow of surface water runoff and groundwater into sanitary sewage collection systems is becoming an increasing priority for wastewater agencies across the United States. Although many people believe that it is beneficial to introduce "clean water" into a sanitary sewer system, the fact is that this additional flow can cause many operational problems, and ultimately increase costs to you, the customer.
Problems caused by excessive flows, commonly called "infiltration and inflow" or "I&I" often include uncontrolled sewer system overflows - causing a sewage discharge to the stream, basement backups, or potential damage to personal property, and impacts to the community sewage treatment facilities - resulting in costly capital improvements.
In addition to making good economic sense, this corrective program is timely, as the US-EPA is now requiring required sewer operators to aggressively implement program geared to eliminating sanitary sewer overflows. This includes all ways that runoff and ground water enter the municipal sewer system from public or private property, including manholes and pipes, as well as downspouts, sump pumps, yard drains, or other means. Most of these connections are violations of the local plumbing codes as well.
In summary, sanitary sewer systems are simply not designed to handle storm water or sump pump waters. This extra water quickly overloads the system’s capacity causing overflows. And when the remaining waters do reach the sewage plant, it causes additional problems by overloading the plant and disrupting the chemical balance needed for proper treatment. Electric, chemical, and other maintenance costs skyrocket.
For example, suppose roof drains on a house are connected to the sanitary sewer, and we have a one-inch rainfall. A 1,200 square foot roof would produce nearly 750 gallons of runoff in a short period. The same rainfall producing groundwater would likely cause a standard sump pump connected to our sanitary system to remove nearly 1,000 gallons of groundwater over a period of six hours. Compare that to the fact that a typical household of 4 discharges only about 300 gallons of wastewater each day.
Even if only a small percentage of the roof drains or sump drains in the community are attached to the sanitary sewer system, on days that it rained only an inch, the sewage treatment plant would have to process nearly one million gallons of additional water!
For the past several years we have been working to locate and repair various sources of water infiltration into our sanitary sewer system throughout the North Wales community. Our efforts have focused upon correcting problems in street manholes and sewer mains within the public roadways. This mostly addresses infiltration and has been the first phase of our I&I program. Click here to view a map that shows which areas of the Borough have the highest rates of infiltration.
We are now prepared to move into the second phase of the program, which involves locating and correcting what is commonly referred to as the "inflow" part of the problem. Despite the success of our infiltration repairs, inflow remains a problem in the community, especially after heavy rainfall, snow melting, and/or during seasonal high water table periods. Click here to view a map that shows which areas of the Borough are most affected by inflow.
Typically, inflow comes from improperly connected sump pumps, downspouts, parking lot drains, yard drains, and sometimes even cross connections with detention or retention basin drain pipes. The property owner can usually correct these issues in a relatively short period, and without the disruption experienced with the recently completed street excavations and repairs - however this work can be nearly as effective in reducing excessive flows.
NWWA has developed a plan that will allow us to implement the inflow portion of our corrective action program in a cooperative manner with you, including both voluntary inspection and correction incentives. We plan to begin this program this summer, and to complete, most, if not all inspections by fall, 2013. Please note that these inspections will be of sump pumps, downspouts, drains, etc. and will NOT include your sewer service line.
As we begin working through the community we will be handing out informational materials door-to-door. It is important to remember all NWWA employees will have PHOTO ID with them during every visit. Please do not hesitate to ask for their ID and call our office immediately at 216-699-4836 if you are suspicious.
Finally, NWWA employees will never ask for payment for any labor, materials and/or supplies needed to perform repairs.