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Historic Preservation - Technical Procedures

Spectitle:

Clearing Blocked Internal Storm Drains

Procedure code:

0764101R

Source:

Internet

Division:

Thermal And Moisture Protection

Section:

Iron Roof Drain

Last Modified:

02/24/2012

Details:

Clearing Blocked Internal Storm Drains



CLEARING BLOCKED INTERNAL STORM DRAINS


PART 1---GENERAL

1.01 SUMMARY

    A.   This procedure includes guidance on inspecting for and
         clearing out blocked internal storm drains.  Prevention
         of potentially blocking debris from entering the drains
         via the roof is an important factor in preventing blocked
         drains.  See 3.01 A.1. and A.2. below for preventive
         maintenance guidance.

    B.   See 01100-07-S for general project guidelines to be
         reviewed along with this procedure. These guidelines
         cover the following sections:

         1.   Safety Precautions

         2.   Historic Structures Precautions

         3.   Submittals

         4.   Quality Assurance

         5.   Delivery, Storage and Handling

         6.   Project/Site Conditions

         7.   Sequencing and Scheduling

         8.   General Protection (Surface and Surrounding)

         These guidelines should be reviewed prior to performing
         this procedure and should be followed, when applicable,
         along with recommendations from the Regional Historic
         Preservation Officer (RHPO).  


PART 2---PRODUCTS

2.01 MANUFACTURERS

    A.   RIDGID/Kollmann
         Ridge Tool Company
         400 Clark Street
         Elyria, OH 44036
         216/323-5581

2.02 EQUIPMENT

    A.   Diagnostic Equipment: High performance durable
         camera/transmitter system equipped with small black and
         white camera head and pipe location transmitter; able to
         negotiate multiple 90 degree bends in 2" to 10", such as
         "SeeSnake Diagnostic Tools" (RIDGID/Kollmann), or
         approved equal.

         Note: Complete system includes camera, push cable, 3" &
         6" centering guides, cable drum and dolly, interconnect
         cable, 9" high resolution B&W monitor with integrated
         power supply, light dimmer and sunshade, operator's
         manual, RCA to RCA video cable, BNC to RCA adapter.

    B.   Drain cleaning equipment such as an auger and/or saw
         tooth cutter (Ridgid/Kollmann), or approved equal, as
         required for the specific blockage type.


PART 3---EXECUTION

3.01 EXAMINATION

    A.   Examine the foundation and exterior of the building by
         walking around the building during a heavy rain storm.
         Look for blocked or broken storm drains, leaking or
         overflowing gutters or perforated downspouts.  Notice
         where water is ponding on the ground around the building.

         1.   Clean gutters and downspouts twice a year - in late
              spring and in late fall.

         2.   Provide screen barriers at gutter outlets to
              prevent debris from entering into the downspout and
              storm drain system.

    B.   Examine interior walls where internal roof drains run
         vertically, to identify staining, failed paint, failed
         plaster or other signs of water damage near the drains.

3.02 ERECTION, INSTALLATION, APPLICATION

    CAUTION: DO NOT ATTEMPT TO FLUSH DRAINS WITH WATER TO REMOVE
    DEBRIS.  EXCESSIVE PRESSURE CAN CREATE INTERNAL LEAKS, CAUSING
    STAINING AND DAMAGE TO ADJACENT BUILDING MATERIALS.  INSPECT
    ANNUALLY; OPEN AND CLEAN-OUT ACCESSIBLE POINTS PERIODICALLY.

    A.   When there is apparent blockage and signs of water damage
         inside the building, use "low-tech" attempts such as
         routers to clear the drain.  If these attempts are not
         successful, it is possible to identify the problem via
         new video tools.

    B.   Identify the problem through video inspection and
         determine the fault location as accurately as possible
         using a high-performance camera/transmitter system.

         1.   Plug in the system and turn on the monitor.

         2.   Push the camera head into the line and continue to
              slowly feed it through.  Follow manufacturer's
              instructions.

         3.   Blockages will be evident on the video monitor as
              viewed by the camera.  

         4.   Once the blockage has been identified, use the
              location transmitter to accurately identify its
              location.  Follow manufacturer's instructions.

    B.   Remove blockages using a mechanical auger or tooth cutter
         as required for the type of blockage.  Follow
         manufacturer's instructions.  If necessary, excavate the
         section of drain line in question and replace any cracked
         or broken pipe.

    C.   Test drain lines between catch basin and municipal storm
         drainage system.

    D.   Replace any missing drain covers to match existing.

                         END OF SECTION