Date: July 11, 1995
                                                Dept. File No.4755-3

   TO:       Vancouver City Council

   FROM:     General Manager of Engineering Services

   SUBJECT:  Fraserview and Still Creek Sewer Inflow and 
   Infiltration Reduction Programs.


        A.   THAT Council authorize City staff to continue to 
   monitor the Fraserview sanitary sewer system and report          back on
   the need for resumption of an inflow and               infiltration
   reduction program if necessary.

        B.   THAT Council authorize the Mayor to write to Burnaby
             Council advising them of Vancouver's Still Creek 
   cleanup program and supporting continued Burnaby            efforts to
   cleanup Still Creek's headwaters in the           Metrotown area.


   Council has previously approved a number of recommendations concerning
   the reduction of pollution levels in the Fraser River, English Bay, and
   Burrard Inlet water bodies.


   This report provides Council with an overview of the results of the
   Fraserview Inflow and Infiltration (I&I) Reduction Program. It also
   requests Council authorization for continued monitoring of the
   Fraserview sanitary sewer system with staff to report back on the need
   for resumption of an I&I program if necessary.  This report also
   provides an update as to progress of the Still Creek I&I Reduction


   In August 1992, Council authorized a $300,000 sewer system I&I reduction
   program for the Fraserview area.  The objectives of this eighteen month
   program were to reduce sanitary sewage overflows to the Fraser River
   from the Elliot Street outfall and to eliminate sanitary sewage
   contamination of Vivian Creek.  A May 1994 Council report provided an
   update as to the progress of this program.

   The 1994-96 Sewers Capital Plan included a three year, $600,000 I&I
   reduction program for the Still Creek area based on the model
   successfully used for the Fraserview area.  This approach was approved
   by Council in the May 1994 report.  As this program obviated the
   immediate need for sewer upgrading to service the Collingwood Village
   Development, VLC Properties contributed $455,000 towards its costs.

   The objectives of the Still Creek I&I Program are to eliminate sanitary
   sewage contamination of Still Creek, to increase the available capacity
   in the sanitary trunk sewer to prevent future flooding, to reduce the
   likelihood and scale of any possible future trunk sewer upgrades needed
   for new developments in the area, and to provide some reduction in
   combined sewer overflows at the Clark Drive sewer outfall.


   Fraserview Program

   Inflow and infiltration are terms used to describe stormwater which
   improperly drains into a sanitary sewer system.  Stormwater can enter
   the sanitary system through leaky manholes, lids, and pipe joints in
   addition to incorrectly connected roof drains, drain tile, and catch
   basins.  I&I flows can sometimes exceed the capacity of the sanitary
   sewer system causing backups into homes or overflows to the environment.

   Measures to reduce I&I flows in Fraserview have included:

       Identifying and correcting connections for fourteen homes found to
        be draining sanitary sewage to storm sewers which drain to Vivian
        Creek.  Eight of these residences were also found to have storm
        connections to the sanitary sewer (reversed connections).

       Identifying and repairing thirty-nine homes with storm connections
        to the sanitary sewer.

       Installing lid sealing gaskets in sanitary manholes found to be
        intercepting significant amounts of street runoff.

   The last of this work was completed in the fall of 1994.  Subsequent
   monitoring of storm sewers which discharge to Vivian Creek has confirmed
   the elimination of any sanitary sewage contamination.

   In addition to these repairs, a short, undersized section of the
   sanitary trunk sewer was upgraded.

   Final flow monitoring of the sanitary sewer system was conducted in the
   spring of this year.  During the ten week monitoring period, thirteen
   significant rainfall events occurred.  Prior to undertaking this
   program, an estimated eleven of these events would have resulted in
   sanitary sewage overflows at the Elliot Street outfall.  This spring,
   however, no such incidents occurred.

   Based on these results, the Fraserview I&I Program has exceeded our
   expectations.  While a storm of considerable magnitude might still cause
   an overflow, the data would suggest that these occurrences have been
   virtually eliminated.  However, ongoing redevelopment of the Fraserview
   area will increase sanitary sewage flows requiring continued efforts to
   curtail I&I.

   One of the remaining significant sources of I&I flows is leaking old
   sanitary service connections.  Fortunately, these pipes are replaced
   with new, more water-tight services upon property redevelopment. 
   Currently, about 2% of the older homes in Fraserview are replaced
   annually.  While extension of the I&I program would result in further
   reduction benefits, staff are not recommending it at this time.  We
   anticipate that I&I reductions gained through the redevelopment process
   will more than offset the increased flows resulting from new
   developments.  We therefore recommend that we continue to monitor the
   Fraserview system and report back on the need for resumption of an I&I
   program if necessary.

   Still Creek Program

   Like Fraserview, the Still Creek area has a sanitary sewer system with
   excessive I&I flows.  The GVRD's Collingwood Sanitary Trunk sewer, which
   drains Vancouver's Still Creek and Burnaby's Metrotown areas, is
   surcharging during wet weather.  In addition, sanitary sewage
   contamination has been found in Still Creek.  

   Experience gained in locating and correcting reversed connections in
   Fraserview is being applied successfully to the Still Creek area.  The
   first stage of this program has focussed on eliminating sources of

   sanitary sewage contamination in the creek.  To date, these efforts have
   located and corrected the following numbers of properties found with
   improper connections.

       Thirty-two properties with storm connections to the sanitary sewer

       Twenty-four of these same properties found to have sanitary sewage
        draining to storm sewers which discharge to Still Creek.

   A further eight properties have been identified with reversed
   connections and corrections to these are currently in progress.  

   The Still Creek drainage area, with 11,000 properties, is approximately
   five times the size of the Fraserview area and is also much older. 
   Approximately 30% of the area has been checked and cleared of faulty
   sewer connections to date.  The relatively large number of properties
   identified with plumbing system problems can be attributed to the fact
   that in some areas the private property sewage systems predate the
   City's sewer system.  Many properties were originally built with septic
   tanks.  When City sewer services became available years later, a few
   homes tied one or both of their sewer systems to the wrong pipe.

   Future activities for the City's Still Creek program will include 
   continued locating and correcting of properties with reversed
   connections, fecal coliform testing of the Still Creek storm sewer
   system, and video inspection of the sanitary sewer system to locate
   leaks.  The GVRD will also be flow monitoring their sanitary trunk sewer
   to identify the extent of surcharging.  This work will assist us in
   tracking the success of our I&I reduction efforts.  The GVRD also plans
   to assess the condition of their sewer through video inspection in the

   City staff are also cooperating with Burnaby on addressing Still Creek's
   I&I problems.  Through this process, Burnaby has recently determined
   that they have I&I problems in their sanitary sewer system upstream of
   Vancouver in their Metrotown area.  Burnaby system problems include wet
   weather sanitary sewer overflows to Still Creek just upstream of where
   it enters Vancouver and improper stormwater connections to the sanitary
   sewer.  City staff recommend that to promote continued consultation at
   all levels, the Mayor write to Burnaby Council advising them of
   Vancouver's program and supporting continued Burnaby efforts to cleanup
   Still Creek's headwaters in the Metrotown area.

   Based on the results obtained to date, sanitary sewage contamination of
   Still Creek from Vancouver sources should be eliminated by the program
   conclusion. In addition, the level of surcharging occurring in the
   Collingwood Sanitary trunk sewer during wet weather should be
   significantly reduced and, subsequently, the danger of flooding abated. 
   Some reduction in combined sewer overflows at Clark Drive should also

   Within two or three years, a decision is expected under the regional
   Liquid Waste Management Plan framework regarding any capital
   improvements necessitated by I&I flows.  City staff expect that the
   results of our I&I reduction program will greatly reduce the scale of
   improvements which may be needed in the Vancouver Sewerage Area.

                       *    *    *    *    *


   City Manager____________________   Report dated: July 10, 1995
   Date____________________________   Author: A. Grill Phone 7453
                                      IRTS Number___________________
   This report has been prepared in 
   consultation with the departments  Concurring Departments
   listed to the right, and they      ______________________________
   concur with its contents.          ______________________________
   Department Head_________________   ______________________________
   Date____________________________   ______________________________