Recommended Addition to a Request for Proposal for
Sanitary Sewer Cured-In-Place Pipe (CIPP) Acceptance & Certification
Insert and Re-Number as Appropriate
8.00 ELECTRO SCANNING INSPECTION
Reliable information on sewer pipe condition is needed to accurately estimate the remaining service life of wastewater collection system assets and to assess pre- and post-rehabilitation effectiveness. In general, sewer pipe condition assessment has been limited to visual inspection techniques. Used primarily during dry weather conditions, adhering to a variety of defect cataloging protocols, few if any condition assessment techniques have allowed asset owners to determine the location and measurement of added flows during wet weather conditions, which contribute to unexpected sanitary system overflows, sewer backup, and sewer pipe failures.
8.01 Scope
The purpose of mainline/lateral electro scanning inspection will be to identify all defects as accurately, efficiently, and as quickly as possible. In older pipes, defects such as groundwater infiltration from open joints, cracks, roots, corrosion, broken or collapsed pipes, and any other irregularities within the pipeline shall be identified and recorded. With new or post-rehabilitated pipes, the technology automatically locates and measures defects in cured in-place lined pipes (CIPP), epoxy resin or fiberglass reinforced lined pipes (FRP), high-density polyethylene (HDPE) pipe, plastic inserted pipes, spiral wound liners, traditional point repairs, and newly installed non-conductive pipes.
As a result, the Contractor will be responsible for identifying all defects, their location by footage, and magnitude of each defect as part of an electronic report to be transmitted to the cloud after each survey. The report shall include an estimate of the physical size of the defect (i.e. length, width, and area), and the potential infiltration of each defect in gallons per minute (GPM), gallons per day (GPD), and gallons per minute per inch diameter miles (GPD/IDM), with total pipe defect flow for each measurement.
The contractor shall provide all licensing for software and services to display all pre- and post-rehabilitation defects in the analytical asset management tool, InfoMaster, by Innovyze, including use of City-provided ESRI ArcGIS platform, capable of displaying both CCTV and Electro Scanning Inspection in a three dimensional representation showing defect locations and severity.
The contractor shall furnish all necessary labor, equipment, materials, services, and incidentals required to record inspection of designated gravity sewer line sections from manhole to manhole by means of Electro Scan Technology, including but not limited to, charts and graphs, and a final overall report.
This project consists of the pre- and post-CIPP survey using the electro scanning inspection.
8.1.a Pre- and Post- Cured-In-Place Pipe (CIPP) Testing & Certification
Acceptance testing and certification of all repairs, relining, and renewal, shall be performed using electro scanning inspection and shall be performed by an independent third-party contractor experienced in the use of the electro scanning system, in accordance with the MAINTENANCE AND OPERATION OF WASTEWATER COLLECTION SYSTEM, Volume 1, Seventh Edition, 2015, ISBN 978-1-59371-066-8 and ASTM F2550-13, Standard Practice for Locating Leaks in Sewer Pipes By Measuring the Variation of Electric Current Flow Through the Pipe Wall.
8.1.b. Electro Scanning Inspection Pipe Liner Test Method
The electro scanning inspection test shall be conducted on one hundred percent (100%) of the total linear footage of mainline pipe, including a Pre-CIPP and Post-CIPP survey, with all results available to the City immediately following the test completion.
Testing shall be performed on all non-conductive lined and host pipes and , including but not limited to, Asbestos Cement Pipe, Brick, Cement Mortar Lined Ductile Iron or Steel Pipe, Ceramic Epoxy, Clay, Concrete, Fiberglass Pipe, High-Density Polyethylene Pipe, Polyvinyl Chloride Pipe, Reinforced Concrete Pipe, Vitrified Clay Pipe, among others.
It shall be the responsibility of the CIPP contractor to accurately identify the host pipe material based on pre-installation TV or historical records.
The electro scanning inspection testing shall be conducted in accordance with the manufacturersrecommended practices.
The electro scanning inspection contractor shall be responsible for any damages topublic or private property resulting from electro scan testing activities.
8.1.c The following limits shall be used to determine the significance of detected defects.
- Anomalies below the “Small Threshold” (<100 mA) are considered acceptable, but may be eligible for investigation at no cost to City. This excludes anomalies detected at the beginning and end of pipe at manholes.
- Anomalies above the “Small Threshold” >100 mA, will be initially considered “unacceptable.” Defects need to be further investigated and reviewed. If deemed unacceptable, the pipe will be failed.
- Anomalies that occur at the beginning and end of a lined pipe, where the probe is exiting or entering a manhole, will not be the responsibility of the contractor and will be accepted by City.
- If no lateral connection rehabilitation will take place, contractor will not be held liable for any anomalies detected at lateral reinstatements. However, lateral reinstatements must be performed to City specification.
- City will have full access to all automatically recorded testing conditions via a cloud-based portal and will be verifying all tests are being performed within the manufacturer’s recommended parameters. All scans must be performed within the following testing parameters:
- Pipe must be fully surcharged with water at the location of the probe to ensure a full 360-degree inspection of the pipe. This can be achieved in whatever way the contractor chooses, but City and manufacturer recommend using a Sliding Funnel plug, in conjunction with a hydraulic jet truck. If chosen, probe must remain a minimum of three (3) feet from funnel plug.
- Total Current readings must be a MINIMUM of 2800mA when probe is in a concrete manhole when starting the scan, and must not drop below 1000 mA after entering the lined pipe.
- Speed must not exceed 40 feet per minute.
8.1.d. CIPP installations shall be considered acceptable when no anomalies are detected.
8.1.e. All pipes with Defects above the “Small Threshold” shall be retested after Contractor has addressed the defect at no additional cost to City.
8.1.f. The Electro Scan contractor shall provide same day fully analyzed results to both the Contractor and City representative within 1hour of testing each section of pipe via uploading each scan to the City’s licensed viewing platform. NOTE: Contractor will not have any access to the City’s viewing platform to maintain independent testing and certification of all tests.
8.2Equipment
The electro scan technology system used for the survey shall be specifically designed and constructed for such inspection. This equipment shall be in full compliance with ASTM F2550-13 with capabilities as outlined in this Standard. These capabilities and proprietary algorithms shall include the following:
-City and State
-Date of Inspection
-Location of Inspection
-Pipeline size, type, and overall length
-Graph showing:
- Defect start / end and overall length (ft.)
- Possible GPM infiltration
- Possible GPM Defect Area (ft.)
- Defect Threshold:
- Small
- Medium
- Large
- Overall chart indicating Defect Flow Summary in detail
- Minor flow and percentage of total flow
- Moderate flow and percentage of total flow
- Severe flow and percentage of total flow
- Total GPM
- Total GPD
- Total GPD/IDM
8.3Performance
The electro scanning inspection shall be performed on one sewer line section (i.e. manhole to manhole) at a time. Flow within the section is irrelevant except within the area of the inspection probe, which will be one hundred percent (100%) flooded or surcharged within three (3) feet of the probe in both directions.
The probe shall be pulled through the line at a uniform rate by a connected water jet truck, in compliance with operator discretion. The rate of inspection should not be greater than 40 feet per minute, and the rate should not exceed the capability of encapsulating the probe with water.
8.4Sewer Main Assessments
For each pre- and post-rehabilitation mainline sewer survey, execution of the electro scanning inspection test will begin with a light flushing of the sewer line, generally to transport the hydraulic jet hose from downstream to upstream manholes, and then using the hydraulic jet hose and reel to pull the electro scan probe through the pipe.
Once the hydraulic jet hose arrives at the upstream manhole, retrieved, and brought to the surface, the jet nozzle will be removed from the hydraulic jet hose at the upstream manhole and a sliding funnel plug will be attached to the hose. Once the funnel plug is connected to the jet house, the electro scan probe will be attached to the plug.
Once lowered into the upstream manhole and positioned towards the downstream manhole, with jet hose retracted to eliminate any excess hose, the electro scan operator will verify all low voltage electric current readings and initiate the electro scan data capture system.
Once the scan has been approved and ready to begin the scan, the hydraulically powered jet truck will then pull the probe through the pipeline while simultaneously providing the water necessary for the probe to electrically examine the pipe walls. Should a pipe segment be surcharged to the point where flushing is not appropriate, other techniques and equipment will be used, including, but not limited to, float lines, parachutes, and immediate-area flow restriction.
During the scanning process, all data will be fed back to the PC via the standard coaxial cable, displaying all critical readings, including but not limited to, footage, speed of travel, total current, and defect current.
Data will be collected for the duration of the scan.
When the probe reached the downstream manhole, the hydraulic jet truck operator will communicate with the electro scan operator and the scan will be completed.
Once the probe data is collected and stored on the field laptop computer, data shall be immediately uploaded to a cloud-based application portal where it will be instantly processed and available for city/engineer/contractor review. Contractor will not be able to access, change, modify, or otherwise re-state any results from the scanning survey as the cloud-based application portal shall be a secure site and only accessible by owner code and pathway security.
All mainline sewers as identified in this contract shall be inspected with the use of an approved supplier of the electro scan technology equipment that meets ASTM 2550-13 standard.
ONLY those licensed and pre-approved by the equipment manufacturer and Owner will be allowed to participate in this contract. Contractors with sub-contractors that have such prior licensing, training, and manufacturers approvable will be allowed to participate but only after having written documentation and certification. Training and certification of the electro scan system usage will only be from the electro scan equipment manufacturer or the local representative of electro scan.
The equipment manufacturer’s custom and proprietary algorithms shall be used to grade the size and type of each leak, structural defects, or other possible defects, and graphically display the defect grade size, corrosion, type and frequency for each manhole-to-manhole pipeline section. In addition, the manufacturer’s software will provide an estimated GPM, GPD, and GPD/IDM for each defect and for the entire pipe segment, in accordance with ASTM 2550-13 reporting standards.
Within thirty (30) days contractor shall provide all vendor recommended data files from CCTV and Electro Scanning Inspection for use in displaying both CCTV and Electro Scanning in a licensed copy of the Innovyze InfoMaster system software program, able to display both CCTV and Electro Scan in the City’s ArcGIS and a three-dimensional pipe viewer.
All tasks as listed aboveshall be provided in the report for each line segment and for the overall project report.
QUOTATION
ITEM No. 1TRAFFIC CONTROL
Item / Unit / Description / Total Price1.1 / Lump Sum / Providing Traffic Control
1.2 / HR / Providing Uniformed / Off-duty Police Officers for
ITEM No. 2CLEAN GRAVITY SEWER LINES AND MANHOLES
Item / Unit / Description / Unit Price / Extended Total Price2.1 / LF / Cleaning and flushing of 6-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.2 / LF / Cleaning and flushing of 8-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.3 / LF / Cleaning and flushing of 10-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.4 / LF / Cleaning and flushing of 12-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.5 / LF / Cleaning and flushing of 15-inch Diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.6 / LF / Cleaning and flushing of 16-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.7 / LF / Cleaning and flushing of 18-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.8 / LF / Cleaning and flushing of 20-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.9 / LF / Cleaning and flushing of 21-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.10 / LF / Cleaning and flushing of 24-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
2.11 / LF / For supplement payment for heavy cleaning, independent of pipe diameter and length (heavy cleaning is defined as more than three passes where ordered by the Engineer), the price per each segment of pipe of: / $ / $
ITEM No. 3 PRE- AND POST-CIPP ELECTRO SCANNING INSPECTION
Item / Unit / Description / Unit Price / Extended Total Price3.1 / LF / Water jetting service to support surcharging to surround the electro scanning inspection probe for assessing sanitary sewer gravity lines, price per linear foot. / $ / $
3.2 / LF / Electro Scanning Inspection of 6-inch diameter sanitary sewer gravity lines,price per linear foot. / $ / $
3.3 / LF / Electro Scanning Inspection of 8-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
3.4 / LF / Electro Scanning Inspection of 10-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
3.5 / LF / Electro Scanning Inspection of 15-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
3.6 / LF / Electro Scanning Inspection of 16-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
3.7 / LF / Electro Scanning Inspection of 20-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
3.8 / LF / Electro Scanning Inspection of 21-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
3.9 / LF / Electro Scanning Inspection of 24-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
3.10 / LF / For supplement payment for access to difficult access manholes, e.g. backyard or back easements. / $ / $
3.11 / LF / $ / $
ITEM No. 4 PRE- AND POST-CIPP CLOSED-CIRCUIT TELEVISION (CCTV) INSPECTION
Item / Unit / Description / Unit Price / Extended Total Price4.1 / LF / CCTV Inspection of 6-inch diameter sanitary sewer gravity lines,price per linear foot. / $ / $
4.2 / LF / CCTV Inspection of 8-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
4.3 / LF / CCTV Inspection of 10-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
4.4 / LF / CCTV Inspection of 15-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
4.5 / LF / CCTV Inspection of 16-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
4.6 / LF / CCTV Inspection of 20-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
4.7 / LF / CCTV Inspection of 21-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
4.8 / LF / CCTV Inspection of 24-inch diameter sanitary sewer gravity lines, price per linear foot. / $ / $
4.9 / LF / For supplement payment for access to difficult access manholes, e.g. backyard or back easements. / $ / $
4.10 / LF / $ / $
ITEM No. 5 DATA COLLECTION, PROCESSING, AND REPORTING
Item / Unit / Description / Unit Price / Extended Total Price5.1 / 1 EA / Licensing for one (1) seat of CriticalSewers® Cloud Application from Electro Scan Inc. for twelve (12) month period. / $ / $
5.2 / 1 EA / Licensing for one (1) seat of InfoMaster sewer analytic tool from Innovyze for twelve (12) month period. / $ / $
5.3 / 1 EA / Data entry and data collection of Electro Scanning Inspection. / $ / $
5.4 / 1 EA / Data entry and data collection of CCTV Inspection, in NASSCO PACP format, including standard electronic file format for all data and video (mp4 format). / $ / $
5.5 / 1 LF / Report Preparation of all Pre- and Post-CIPP Inspection, including CCTV, Electro Scanning Inspection comparisons. / $ / $
SUBTOTALS THE TOTAL OF ITEMS 1 TO 5, THE SUM OF$______
Terminology
Amplitude / As related to an Electro Scan electric trace, the height of the signal for a wave of electric current.ASTM / American Society of Testing and Materials. Former name of ASTM International, a globally recognized leader in the development and delivery of international voluntary consensus standards. Today, some 12,000 ASTM standards are used around the world to improve product quality, enhance safety, facilitate market access and trade and build consumer confidence.
Calcification / A buildup of calcium deposits on the wall of a pipe. Over time, heavy calcification can significantly restrict flow.
CIPP / Cured-in-Place Pipe (CIPP) is a trenchless pipe rehabilitation method that uses a resin-saturated felt material to line the walls of an existing pipe
CCTV / Closed circuit television inspection. A subjective technique to view the inside of sanitary sewer pipes that relies on visual observation and judgment to visually identify and manually record defects. A variety of independent organizations maintain different standards with no generally accepted international standard.
Electric Current
Flow / A flow of electric charge through a medium typically carried by moving electrons in a conductingmaterial such as water.. As it pertains to electro scan technology, electric current refers to the charge from a focused electrode in an electrically nonconductive pipe traveling along the inside of the pipe before reaching a ground electrode.
Electrode / A conductor that emits an electric current.
Encrustation / Layers of salt deposits, or other sediments, that adheres to the pipe wall.
Exfiltration / Fluid exiting a pipe through defects in the pipe wall.
Fernco Coupling / A type of coupling used to connect two pipe segments together.
Focused Current / The electrical current flowing through a center electrode of the probe. Relative completeness of a focused current will depend on the electrical resistivity of the pipe wall within the area of the band around the circumference of the pipe.
Ground Electrode / A reference point in an electrical circuit from which other voltages are measured, or is a common return path for electric current or a direct physical connection to the Earth.
Infiltration / Water entering a pipe through defects in the pipe wall. Similar, but opposite, of exfiltration.
Interceptor / Typically a large diameter pipe that acts as a main “trunk” of a sewer system. The interceptor is fed from sewer mains, which are fed by sewer laterals.
Lateral / Typically a small diameter pipe that connects to a main sewer line. For example, the sewer pipe connecting a residential home to the main sewer line is a lateral. Also referred to as a service lateral.
Probe / An electro scan electrode placed in a pipe that typically provides a three-electrode array to scan the inside of a sewer pipe.
Scan / Variations of the electric current over distance is recorded and displayed as a plot. This plot is called a scan.
Surface Electrode / Refers to an electrical device that connects from the earth to the electro scan system, via an earth cable.
Total Current / A system to measure the sum total of the electrical current flowing through electro scan’s three electrodes.
Supplying Electro Scanning Inspection Services for CIPP CertificationPage 1