HomeMy WebLinkAboutSewage Pumping PlantsJuly Ut 1957
V-LA,
REPORT ON SEWAGE PWING PLANTS
Of
THE CITY OF NEWPORT IWACHt CALIFORNIA
including
RECOMMATIONS FOR DIPROVEMENTS
and
ESTIMATED CONSTRUCTION COSTS
I
By: Joseph Kellogg Rice
Civil Engineer
:,
9AUT°ORIZATIO11 AND PURPOSE •
The City Council on June 10, 1957 authorized the employment of the writer
to make a survey and report on the City's sewage pumping plants, with recommenda-
tions.for improvements and estimated costs thereof.
The principal purposes of the survey were:
A. To de.- ermiae.means of eliminating undue detention
of sewage in wet wells as a part of the City's
efforts to prevent build up of sulfides in its
sewer lines and coincidentally reduce odor nuisance.
B. To make a preliminary estimate of costs involved.
However, progress of the survey indicated desirability of increasing the
scope of the proposed work to provide better access to the plants, safety
measures, and improved working conditions for maintenance forces.
RECOMMENDATIONS AND ESTIMATED. COSTS
The following tabulation gives a brief description of the major improve-
ments recommended to each plant together with a preliminary estimate of costs
involved on a contract basis.
Plant No. Name Proposed Improvements Estimated Cost
6 Bay Island* Minor Modifications by City Forces $ None
7 Lido Isle Variable speed, matched flow pump- $ 30,451
ing with wet well converted to
influent channels. Access by
stairways. New electrical control
room above ground.
10 Section 5 Variable speed, matched flow pump- $ 29,859
(Balboa Island) ing. Increase pump room size to
provide legal space for electrical
controls. Convert wet well to
influent channel. Stairway to
pump room.
11 Diamond St. Fixed speed, matched flow pumping: $ 13,729
Convert wet well to influent channel.
Stairway to Pump Room. Revise
electrical system.
i
12 Harbor Island Pneumatic Ejector. Convert wet $ 8,027
well to manhole. Stairway to
pump room. Replace electrical
equipment.
13 Carnation Ave. Pneumatic Ejector: Convert wet $ 7,908
well to manhole. Construct stair-
way.
-1-
3
• •
Plant No. Name Proposed Improvements Estimated Cost
14 China Cove Pneumatic Ejector. Replace existing $ 8,542
access shaft with 6 foot square
chamber to above ground level.
Provide hatch cover and ships ladder.
Abandon existing wet well and con-
struct new inlet manhole.
15 Buck Gulley Variable speed, matched flow pumping. $ 21)946
Convert wet well to influent channel.
Ships ladder and doorway access to
pump room. Extend motor room (above
ground) to provide legal space for
electrical controls.
16 Shore Cliffs Pneumatic Ejector. Convert wet well $ 7,231
to manhole.' Replace 2 foot access
manhole with 5' -6" square chamber
to sidewalk level including hatch
cover and ship's ladder. Replace
electrical equipment.
17 Balboa Blvd. Pneumatic Ejector. Eliminate wet 51962
well. Retain one pump as emergency
stand -by. Enlarge access hatch and
provide ship's ladder.
18 Main Beach* Retain existing pumps. Minimize $ 2,020
detention period in wet well.
Enlarge access hatch and provide
ship's ladder. Replace electrical
equipment.
19 Collins Island* Minor modification by City Forces None
Total Estimated Contract Cost for Proposed Improvements...$ 135,675
* See explanitory statement on Page 3 of this report.
A more detailed breakdown of proposed items of work and estimated costs
for each plant is provided in a book of pumping plant data which has been com-
piled and turned over to the Director of Public Works. The electrical item in
each estimate has been provided by the City and a copy of a report is attached
to the back cover of the book.
This data book also contains a record of the determination of present and
projected sewage flows, and the graphs and calculations necessary to determine
capacity of the major items of equipment recommended.
In addition, the Director of Public Works has been furnished a set of
prints of the existing plants, on which has been sketched in red pencil, the
major items of the proposed improvaments.
-2-
k.
EiiliAN AND =EENTS ON RECOMENDATIONS
(A) Plants No. 6 (Bay - Island) and No. 19 (Collins Island)
Plant No. 6 is too small to allow installation of an ejector as recommended
in other plants with very low sewage flows.- A satisfactory new plant would
involve costs in the order of $10,000.
Since the sulfide and odor conditions are not critical and access is good,
it is recommended that only the following work be done at present:
Reduce wet well detention by lowering the levels of "on" and "off"
controls as much as feasible and providing an air release opening in
the pump volute to prevent air binding.
The same comments apply to the Collins Island Plant (only one house served
at present), except that the access is not satisfactory and that the air
release must be piped back to the wet well. Also, periodic flushing with
fresh water is recommended.
(B) Plants No. 11 (Diamond St.). No. 7 (Lido Isle) and No. 15 (Buck Gulley)
Plant No. 11 is the only location where "Fixed Speed, Matched Flow" pumping
is recommended. This system is much less expensive and simpler than the variable
speed drive, which is the commonly accepted solution for matched flow pumping.
To the writer's knowledge it has been done only with "Torque Flow" pumps and,
only as test operations. However, the conditions of low head and not extreme
variation between high and low flows at this location are favorable for use of
this system.
A similar installation is presently being made by Orange County Sanitation
Districts and one is being designed by Los Angeles County Sanitation Districts.
Also, the pump manufacturer is making a series of tests which should provide
definite data on this system of operation.
Should further favorable experience with this system of pumping be available
in time, it could be used in the final design of Plants 7 and 15 instead of the
variable speed drives recommended.
(C) Plant No. 10 (Section 5)
The recommendation for variable speed drive in Plant No. 10 is firm, since
the flow is large enough to justify a conventional centrifugal pump and the use
of a Torque Flow flow pump would require the use of 30 H.P. motors as against
15 H.P. for the conventional pump.
(D) Plant No. 18 (Main Beach)
.Plant No. 18 has a wide range from high to low flow and the head is too
high for practical use of an ejector as it would require a 30 H.P. compressor.
Also, 'a variable speed drive would not be economically justified by the small
flows involved.
—3—
'�L
• 0
Further, a reasonable projection of future flows cannot be made until the
nature of the future beach development is decided.
For the above reasons no change in pumping is recommended at present in
connection with the work proposed.
VENTILATION
It is recommended that all dry wells be provided with continuous ventila-
tion at a rate of about 10 changes of air per hour.
ACKNOWLEDGEMNT
The writer wishes to express thanks for the excellent cooperation and
assistance extended by the Director of Public 'Works and his staff in obtaining
the data necessary for the preparation of this report.
Respectfully submitted,
Jo ph Kellogg e
vil Engineer
July 11, 1957
JKRsps
F M
July 11, 1957
REPORT ON SEWAGE PUMPING PLANTS
THE CITY OF NEWPORT BEACH, CALIFORNIA
including
RECOMMENDATIONS FOR IMPROVEMENTS
and
ESTIMATED CONSTRUCTION COSTS
C�
By: Joseph Kellogg Rice
Civil Engineer
C.
0UTTEORIZ ATION AND PURPOSE •
The City Council on June 10, 1957 authorized the employment of the writer
to make a survey and report on the City's sewage pumping plants, with recommends-
tions for improvements and estimated costs thereof.
The principal purposes of the survey were:
A. To de-..ermine means of eliminating undue detention
of sewage in wet wells as a part of the City's
efforts to prevent build up of sulfides in its
sewer lines and coincidentally reduce odor nuisance.
B. To make a preliminary estimate of costs involved.
However, progress of the survey indicated desirability of increasing the
scope of the proposed work to provide better access to the plants, safety
measures, and improved working conditions for maintenance forces.
RECOMMENDATIONS AND ESTIMATED COSTS
The following tabulation gives a brief description of the major improve=
ments recommended to each plant together with a preliminary estimate of costs
involved on a contract basis.
Plant No. Name Proposed Improvements Estimated Cost
6 Bay Island* Minor Modifications by City Forces $ None
7 Lido Isle Variable speed, matched flow pump- $ 30,451
ing with wet well converted to
influent channels. Access by
stairways. New electrical control
room above ground.
10 Section 5 Variable speed, matched flow pump- $ 29,859
(Balboa Isla_id) ing. Increase pump room size to
provide legal space for electrical
controls. Convert wet well to
influent channel. Stairway to
pump room.
11 Diamond St. Fixed speed, matched flow pumping. $ 13,729
Convert wet well to influent channel.
Stairway to Pump Room. Revise
electrical system.
12 Harbor.Island Pneumatic Ejector. Convert wet 8,027
well to manhole. Stairway to
pump room. Replace electrical
equipment.
13 Carnation Ave. Pneumatic Ejector. Convert wet 7,908
well to manhole. Construct stair-
way..
-1-
0 0
.Plant No. Name Proposed Improvements Estimated Cost
14 China Cove Pneumatic Ejector. Replace existing $ 8,542
access shaft with 6 foot square
chamber to above ground level.
Provide hatch cover and ships ladder.
Abandon existing wet well and con-
struct new inlet manhole.
15 Buck Gulley Variable speed, matched flow pumping. $ 21 946
Convert wet well to influent channel.
Ship's ladder and doorway access to
pump room. Extend motor room (above
ground) to provide legal space for
electrical controls.
16 Shore Cliffs Pneumatic Ejector. Convert wet well $ 72231
to manhole. Replace 2 foot access
manhole with 5' -6" square chamber
to sidewalk level including hatch
cover and ship's ladder. Replace
electrical equipment.
17 Balboa Blvd. Pneumatic Ejector. Eliminate wet S 52962
well. Retain one pump as emergency
stand -by. Enlarge access hatch and
provide ship's ladder.
18 Main Beach* Retain existing pumps. Minimize S 22020
detention period in wet well.
Enlarge access hatch and provide
ship's ladder. Replace electrical
equipment
19 Collins Island* Minor modification by City Forces None
Total Estimated Contract Cost for Proposed Improvements ... $ 135,675
* See explanitory statement on Page 3 of this report.
A more detailed breakdown of proposed items of work and estimated costs
for each plant is provided in a book of pumping plant data which has been com-
piled and turned over to the Director of Public Works. The electrical item in
each estimate has been provided by the City and a copy of a report is attached
to the back cover of the book.
This data book also contains a record of the determinm tion of present and
projected sewage flows, and the graphs and calculations necessary to determine
capacity of the major items of equipment recommended.
In addition) the Director of Public Works has been %furnished a set of
prints of the existing plants, on which has been sketched in red pencil, the
major items of the proposed improvements.
-2-
EXPWAON AND CONIMNTS ON RECONMENDATOS
(A) Plants No 6 (Bay Island) and No 19 (Collins Island)
Plant No. 6 is too small to allow installation of an ejector as recommended
in other plants with very low sewage flows. A satisfactory new plant would
involve costs in the order of $10,000.
Since the sulfide and odor conditions are not critical and access is good,
it is recommended that only the following work be done at present:
Reduce wet well detention by lowering the levels of "one' and "off"
controls as much as feasible and providing an air release opening in
the pump volute to prevent air binding.
The same comments apply to the Collins Island Plant (only one house served
at present), except that the access is not satisfactory and that the air
release must be piped back to the wet well. Also, periodic flushing with
fresh water is recommended.
(B) Plants No 11 (Diamond St) No. 7 (Lido Isle) and No. 15 (Buck Gulley)
Plant No..11 is the only location where "Fixed Speed, Matched Flow" pumping
is recommended'. This system is much less expensive and simpler than the variable
speed drive, which is the commonly accepted solution for matched flow pumping:
To the writer's knowledge it has been done only with "Torque Flow" pumps and,
only as test operations. However, the conditions of low head and not extreme
variation between high and low flows at this location are favorable for use of
this system.
A similar installation is presently being made by Orange County Sanitation
Districts and one is being designed by Los Angeles County Sanitation Districts..
Also, the pump manufacturer is making a series of tests which should provide
definite data on this system of operation.
Should further favorable experience with this system of pumping be available
in time, it could be used in the final design of Plants 7 and 15 instead of the
variable speed drives recommended.
(C) Plant No. 10 (Section 5)
The recommendation for variable speed drive in Plant No. 10 is firm, since
the flow is large enough to justify a conventional centrifugal pump and the use
of a Torque Flow flow pump would require the use of 30 H.P. motors as against
15 H.P. for the conventional pump.
(D) Plant No. 18 (Main Beach)
Plant No. 18 has a wide range from high to low flow and the head is too
high for practical use of an ejector as it would require a 30 H.P. compressor.
Also, a variable speed drive would not be economically justified by the small
flows involved.
—3—
0 0
Further, a reasonable projection of future flows cannot be made until the
nature of the future beach development is decided.
For the above reasons no change in pumping is recommended at present in
connection with the work proposed.
VENTILATION
It is recommended that all dry wells be provided with continuous ventila-
tion at a rate of about 10 changes of air per hour.
ACKNOWLEDGEMENT
The writer wishes to express thanks for the excellent cooperation and
assistance extended by the Director of Public Works and his staff in obtaining
the data necessary for the preparation of this report.
JKR:ps
Respectfully submitted,
Jo eph Kellog �ce
Civil Engineer
July ll, 1957