FREQUENTLY ASKED QUESTIONS
Department of Engineering
Infiltration/Inflow Service Area Investigations
The District is embarking on a program of infrastructure/capital improvements to protect the public health and safety as well as comply with regulatory requirements. One of the goals of this program is to prevent basement backups after storm events. Many of these basement backups are caused by aging sewers throughout the District’s 524-square-mile service area. One of the programs that will be conducted as part of the infrastructure / capital improvement program involves the field inspection of the condition of the sewers within the District’s system. These field investigations began in July 2003 and are expected to continue until at least July 2006.
Frequently Asked Questions
1. What work is being performed by the inspectors that I see working out of the inspection vans in my neighborhood?
2. Why is this field work being conducted?
3. How will I know when smoke testing will be conducted in my neighborhood?
4. What do I do if I detect smoke in my home during the testing?
5. Who can I contact for additional information?
1. What work is being performed by the inspectors that I see working out of the inspection vans in my neighborhood?
Manhole Inspections
Manhole inspections consist of visual evaluation of the condition of the manhole and the sewer pipes that enter the manhole. The field inspectors descend the manholes and collect various data that is then analyzed in the office. At no time should the field inspectors enter a resident's home during the inspection. Should a manhole be located in the backyard of a resident's home, the inspectors have been instructed to knock on the door to gain permission to enter the yard. All field personnel will be uniformed and carry identification badges at all times.
Smoke Testing
During this test, smoke blowers are placed on manholes and smoke is blown through the sewer system. Anywhere the smoke exits, there is potential for storm water to enter the sewer system. The smoke that you will see coming from the vent stacks on the roofs of homes or from holes in the ground has a slight odor but is non-toxic, harmless and creates no fire hazard. The smoke should not enter your home unless you have some type of defective plumbing or one or more of your drain traps have dried up. You should pour water in any infrequently used sinks or floor drains any time prior to the smoke testing to avoid the smoke entering your home through a dry trap.
If smoke does enter your home please contact the field inspectors out in the street or call 314.378.8011. An updated work schedule of smoke testing by area is available at www.rjn.com. Anyone with any questions or concerns are asked to contact Bob Januska at 314.588.9764 for further information. Field inspectors document the testing by taking pictures of the area and measuring distances so that the defect may be found at a later date and repaired. The inspectors also draw a sketch of the area to aid in location of the defect. During this phase of testing the inspectors may need to walk on the resident's property. At no time should the inspectors need to enter a resident’s home.
Dyed Water Flooding
During smoke testing defects located along the main sewer may be identified. These defects will be further tested using a procedure called dyed water flooding. The area where the defect was observed is "flooded" with non-toxic and harmless green dye from a large tank mounted on a trailer. If the dye water appears in the sewer system then the sewer line is flagged for internal television inspection to determine the exact location and source of the defect. All field personnel will be uniformed and carry identification badges at all times
Television Inspection
Television inspection can also be used to determine the condition of the sewer lines. The video camera inspection will identify the type and the severity of the sewer line defect. This information will be used to develop a repair plan for the sanitary sewer system. All field personnel will be uniformed and carry identification badges at all times. (back to top)
2. Why is this field work being conducted?
The field inspection work is being conducted to determine the condition of the sewers. This will help the District to plan and complete the necessary repairs and improvements to the sewers that are required to reduce or eliminate basement backups and sewer system overflows into the environment. (back to top)
3. How will I know when this Smoke testing will be conducted in my neighborhood?
Inspectors will place smoke notices on residents’ doors 48 hours in advance of smoke testing. The inspectors will have five business days after this to complete the smoke testing in your neighborhood before re-notification of the resident or business is conducted. This testing cannot be conducted during rainy periods, so it can sometimes be delayed after the first door hanger notice is placed. Some sewer lines are located in backyards and easements. The inspectors will need access to the backyards and easements in order to perform the smoke testing procedure. All field personnel will be uniformed and carry identification badges at all times. At no time should the inspectors need to enter a resident’s home. (back to top)
4. What do I do if I detect smoke in my home during the testing?
There is a potential for smoke to enter a business or residence. Smoke could be from drains that have not been used for an extended period (pour a gallon of water down the drain), shower drains, washing machine connections, drains with no p-trap installed, and defective seals around the base of toilets. If smoke does enter your home, open some windows immediately and it should dissipate quickly. In addition, please notify the inspectors in the street that are performing the testing. If smoke is seen from any of these sources a licensed plumber should be contacted to repair the defect. (back to top)
5. Who can I contact for additional information?
You may contact the RJN staff listed below with any comments or questions that may arise.
