A3
   ADMINISTRATIVE REPORT


                                           Date:  January 17, 1997
                                           Dept. File No. 1.40.97.01 
                                           C.C. File: 5809-1


   TO:       Vancouver City Council

   FROM:     General Manager of Engineering Services

   SUBJECT:  Watermain Flushing Program


   RECOMMENDATION

        A.   THAT   the  water  main   flushing  program  be  significantly
             increased with a goal of flushing all water mains of less than
             16 inch diameter annually.

        B.   THAT  the 1997  waterworks operations  budget be  increased by
             $210,000 to accommodate the new program and that an additional
             $24,000 be  allocated for equipment expenditures  in the first
             year, all of which will be funded through water rates.

        C.   THAT Council request to the GVWD Board that the City receive a
             credit for the water used in this program.

        D.   That  Engineering  Services  report  back   to  Council  after
             completion  of  the 1997  program  with  results and  proposed
             refinements. 

   COUNCIL POLICY

   In October 1990, Council  approved in principle the GVRD  Drinking Water
   Quality Improvement Plan.

   On  Sept 24,  1996, Council  approved the  1997-1999 Waterworks  Capital
   Plan,  which  includes  the  strategy that   Drinking  water  quality is
   addressed  through a combination of City and District programs, with the
   City  cooperating in  the  implementation  of  the  GVWD  Water  Quality
   Improvement Program .

                                     - 2 -


   PURPOSE

   This report proposes that the City increase its current flushing program
   to improve water quality by reducing bacterial regrowth, as part of City
   and Regional water quality improvement initiatives.

   BACKGROUND

   The  waterworks distribution system of the City of Vancouver operates on
   a  utility  basis,  with the  City  purchasing  water  from the  Greater
   Vancouver  Water District (GVWD)  supply system  and distributing  it to
   water consumers within the City on a cost-recovery basis, including debt
   charges.  Cost recovery is through metered and flat rate water fees.

   A  June  1996  consultant report  prepared  for  the  GVWD urges  member
   municipalities  to   give increased  funding  priority  to flushing  and
   cleaning of  the water mains on an annual basis to aid the effectiveness
   of secondary disinfection .

   Cleaning  watermains through flushing  is a  key element  to maintaining
   good water  quality in  the  distribution system.  Flushing consists  of
   isolating a  watermain from  the distribution  grid  and flushing  water
   through it by opening one or more fire hydrants.  By flushing the mains,
   most  sediment and  some tuberculation  (corrosion buildup)  is removed,
   removing  bacteria and reducing the surface  area where bacteria regrow.
   This allows  the disinfectant  (chlorine) to work  more effectively  and
   last longer, improving water quality.

   DISCUSSION

   The existing  City flushing  program sees  flushing  conducted in  areas
   where water quality becomes a concern.   These areas are identified each
   year through our  water quality  monitoring program.   Flushing is  also
   done in  response to dirty  water complaints, and  on dead-end  mains as
   crew time permits.  The 1996 annual flushing budget  was $110,600.  This
   program results in  approximately 2  percent of the  water system  being
   flushed annually.

   With  the implementation  of its Drinking  Water Treatment  Program, the
   District is now strongly  urging all member municipalities to  regularly
   flush  their entire water distribution systems.  The District feels that
   the success of their treatment improvements depends upon clean municipal
   distribution systems.  Without watermain cleaning, bacterial regrowth is
   expected to be an ongoing problem.
                                     - 3 -


   In Vancouver,  widespread watermain cleaning will  require a significant
   increase in the resources allocated to this task, adjustments in methods
   so  that larger  areas  can be  flushed  more quickly,  reallocation  of
   existing funding  from other  programs, and increased  overall operating
   budget funding.  
   In  an attempt to develop  a comprehensive proposal,  staff have carried
   out a  pilot program in the fall of 1996.   The proposed 1997 program is
   based  on our  knowledge and  experience gained  through the  fall pilot
   program.   We will report back  to Council after completion  of the 1997
   program with the results and any proposed refinements.

   The  flushing  program would  be conducted  at  night to  minimize water
   quality impacts as  well as  disruptions to neighbourhood  areas due  to
   large  volumes  of  water  in the  street.    Due  to  possible freezing
   temperatures  in the winter,  and water conservation  initiatives in the
   summer,  the  proposed annual  flushing  program would  be  conducted in
   March, April, May, October and November.

   The  flushing  program   will  include  all   watermains  in  the   City
   distribution  system 16 inches in diameter and smaller.  Larger diameter
   watermains  are not included  in this program  as the quantity  of water
   required  for  an effective  flush is  prohibitive.   These  mains would
   typically  be   pigged  (mechanically   cleaned),  although   much  less
   frequently.

   Six two person  crews would be  required to conduct  the program,  along
   with one  Foreman to organize  and supervise.   In addition, one  person
   chlorine crews would be  used to add chlorine  on a trial basis in  some
   areas of the City with little or no chlorine residual.

   Water  from each flush is disposed  of through the City s combined sewer
   system, which is generally  treated at the Iona Island  Sewage Treatment
   Plant.   In  those  areas  where  the  storm  sewers  drain  into  local
   waterways,  the  water will  be  either  dechlorinated before  disposal,
   trucked  to  areas where  the  storm  sewer  leads  to the  City  sewage
   treatment facility, or disposed through the sanitary sewer system.

   FINANCIAL IMPLICATIONS

   Equipment Costs

   One  time costs for the  acquisition of chlorine  equipment and metering
   kits, turbidity  kits,  hose  and appurtenances  for  this  program  are
   estimated at  $24,000.  These  costs are to  be recovered from  the 1997
   water operating budget. 
                                     - 4 -


   Program Annual Costs

   The total estimated cost of the proposed program is $402,000 for 1997.  
   The  General Manager  of Engineering  Services recommends  that  this be
   funded  through  a combination  of  existing  watermain flushing  funds,
   reallocating  portions of other existing waterworks operational funding,
   and some increased funding.

   Although the cost estimate is based  on the pilot program implemented in
   the fall of 1996, we have not previously carried out  a flushing program
   on  the scale  proposed.   Our ability  to complete  the program  at the
   estimated  cost will be dependent  on a number  of factors including the
   productivity we are  able to achieve on a program of  this size, and the
   need  for  chlorination and  dechlorination as  a  part of  the flushing
   process.  We will report on the success of this program and the need for
   any budget adjustments to meet the goals of the program after completion
   of the 1997 program.

   Many water main valves  and some fire hydrants  will be operated  during
   the flushing procedure.   The  City currently inspects  and repairs  all
   main  valves, and  fire  hydrants  regularly.    By  combining  the  two
   processes, inspecting and noting deficiencies on any hydrants and valves
   operated  while  flushing, some  efficiencies can  be  realized.   It is
   therefore proposed that the following  operating budgets be reduced  and
   the resulting available funds be added to the flushing program:

   Waterworks Budget Item                1996 Budget      Reduce By

   Repair and Maintenance Hydrants       299,800           20,000

   Valve Inspection Routine Maintenance  541,800           60,000

                       Total                               80,000

   In 1996, our watermain flushing budget was $110,600.  When combined with
   the above reallocations, the resulting net increase required in the 1997
   Waterworks Operations Budget would be $210,000.

   On November 26, 1996,  Council reviewed and approved the  proposed water
   rates for  1997.   These  rates included  an  allowance for  a  $200,000
   funding increase to accommodate increased watermain flushing, subject to
   Council s  review  of  today s  report.   The  slightly  higher proposed
   increase would not alter the 1997 water rates.

                                     - 5 -


   This  funding is  probably  not  adequate  to  flush  the  whole  system
   annually,  but  frequency  will  improve as  secondary  disinfection  is
   implemented throughout the  rest of  the City (decreasing  the need  for
   chlorination  during  flushing)  and  as  the  condition of  the  system
   improves with repeated cleaning and better source water treatment.

   RELATED ISSUES

   Water Cost

   In  addition to  the program  operating funds,  a significant  amount of
   water  will be  consumed  for  this  flushing  program,  which  must  be
   purchased from the GVWD.   The estimated water cost is $225,000  at 1997
   rates.  This cost  is not reflected in the estimated  program costs.  It
   will  be reflected in increased  water purchase billings  from the GVWD.
   It is  proposed that Council  request to  the GVWD Board  that the  City
   receive a  credit for the water used in this  program.  If the credit is
   not received, these water costs will be reflected  in an increased water
   purchase  from  the GVWD,  which  can be  funded  from  the Water  Rates
   Stabilization  Reserve  for 1997,  and from  the  water rates  in future
   years.

   The  GVWD is asking municipalities  to cooperate in  their Water Quality
   Improvement programs by increasing their flushing programs.  It would be
   reasonable  for them to support the efforts of those municipalities that
   participate in this effort by not charging for the water used.

   Sewage Treatment Costs

   Most  of  the flushed  water  will be  treated  at the  sewage treatment
   facility  at Iona  Island.   Because the flushing  program does  not run
   during  the driest  months  when the  lowest  sewage flows  are  usually
   recorded (the  City pays for sewage  treatment based on the  lowest 25th
   percentile of flows), there is little chance  of a significant impact on
   sewage treatment costs.

   ENVIRONMENTAL IMPLICATIONS

   Flushed water will be disposed of  via the existing street stormwater or
   sanitary sewer  system.  For the  vast majority of the  City, this water
   will be treated  at the Iona  Island Sewage Treatment  Plant.  In  those
   areas  where chlorinated  water would  be discharged directly  to marine
   habitat,  flushed  water  will  be  dechlorinated  before  entering  the
   stormwater  system, discharged to the  Sanitary Sewer, or  trucked to an
   area that receives  treatment.  There should  be no negative effects  on
   the environment.

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