HomeMy WebLinkAboutCommittee of the Whole Minutes 09.05.19951 M
MINUTES
CITY COUNCIL COMMITTEE OF THE WHOLE
SEPTEMBER 5, 1995 6:30 P.M.
COUNCIL CHAMBERS
MEMBERS PRESENT: Chairman- Chuck Rodgers
Ron Marshall Chuck Dickerson
Albert Ehrlick Gay Easton
John Minch Donna Kilpatrick
Bob Graham Lonnie Kellogg
OTHERS PRESENT:
V. Joe Leckie
Jim Flisrand
Vicki Metzger
Don Hackmann
D.L. McGillen
Mike Atkinson
Dave Michael
Lonnie mentioned that a person in his ward had a complaint. He was
in a local bar on 2 different occasions the past couple of months
when a few firemen who had been in there drinking, answered a fire
call. This guy was rather disturbed and Lonnie told him that he
would mentioned it to the council. Chuck Rodgers responded by
saying that the firemen are volunteers and they were on their own
time.
Lonnie also mentioned that John Alden Life turned us down for
health coverage and that we have been re-instated by Mutual
(United) of Omaha.
We were not sure at the time if United of Omaha would re--instate us
so Lonnie contacted Mick Defronzo, an insurance consultant. It was
not necessary to hire him at this time, but Lonnie recommended that
we hire a consultant sometime in the near future when we go out for
bid.
The Police Department hands problems on a complaint basis and write
tickets when they see violations, but Lonnie feels that if you are
out driving around and see a violation, such as an abandoned car,
it should be reported.
Chuck Dickerson mentioned that the new flags at City Hall look
nice.
Discussion regarding 90 gallon garbage cans on First Avenue and on
West 9th.
Chuck asked about Fox Lumber and Joe reported that the trial which
was set for a week ago has been postponed for 2 weeks. More
information should be available by the next council meeting.
Albert had a question regarding the sewer line at the new Ford
garage building. He wanted to know if they were going to run their
storm sewer into our ditch.
Jim and Dave said that they will have a french drain system which
will drain into a holding pond. When that overflows it will drain
into a drainage easement that runs north of the Equipment Finders.
Donna expressed concern about Connie Lind marking cars downtown.
They are so few and far between, sometimes a block apart, and she
feels that it is a waste of time.
Discussion regarding the parking/animal control officer possibly
looking for abandoned cars around town.
Jim distributed and reviewed the DPW update of 9--5-95.
Joe mentioned that in your correspondence for tonight there is a
copy of a letter written to the Attorney General regarding the
O'Toole situation.
Mike reported that there is a Police Committee meeting Thursday,
September 7th at 5:00 p.m.
Discussion regarding trees and bushes obstructing the view at
intersections and about placing stop signs at strategic locations.
Jim will put together some information and bring it to the next
Street & Alley committee meeting.
Joe informed the Council that on the agenda tonight is an item for
their consideration regarding the amendment of minutes. The
minutes should reflect the Council's deliberations and the
transaction of business. He cautioned the Council to be careful
when they have people coming in and recommending that they make
certain amendments.
He doesn't think that the Council should consider someone else's
private agenda when considering what should be in the minutes.
It is Lonnie' s understanding that according to the Roberts Rules of
Order, minutes should only be amended if it is actually going to
change public record, such as consideration of an item, or the way
someone voted, or the schedule of an event. Joe said that was
right, except the minutes can reflect the Council's deliberations
to the extent that they want.
Discussion regarding the Merchant apartments. Ed Leuthold
contacted Joe last week and indicated that bids have been received
to tear it down. They are checking what procedures to use and
exactly what has to be done because of the asbestos siding.
Discussion regarding the Animal Control Officer/Parking Attendant
enforcing the delivery permit ordinance. Mike will take a look at
this.
The meeting was adjourned at 6:58 p.m.
Respectfully submitted,
Don Hackmann, City Clerk
FROM: Jim Flisrand, Director of Public Works
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TO: Mayor and City Council
DATE: September 5, 1995
SUBJECT: Public Works- UPDATE
STREET & ALLEY
1. Continuing our street maintenance programs including pothole
patching, sweeping.
2. Sign replacement.
3. Mowing public right-of-ways.
4. Painting crosswalks & stop bars.
5. Trimmed trees blocking view of street signs.
PARKS & CEMETERY
1. Equipment, building and ground maintenance continuing
throughout the parks, cemetery maintenance, as needed.
2. Repaired eight damaged sprinkler heads at Murray Park
(vandalism).
WATER & SEWER
1. Meter replacement and testing program, will begin again in
September, following summer construction.
2. Plants continuing with normal treatment and maintenance
activities.
3. Water Improvements Project continuing with preliminary
engineering and collection of field data.
SOLID WASTE
1. Proceeding with collection and container site operation as
required.
ADMINISTRATION
1. Building activity is typical of this time of year.
2. Working with the State Building Department to increase the
City's inspection area.
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At.
EXECUTTVE
SUMMARY
1.1 INTRODUCTION
Morrison-Maierle, Inc. was authorized to evaluate four preliminary design concepts prior to
initiating project design to upgrade the City of Laurel's Water Treatment Plant. This report
summarizes the evaluations performed and makes recommendations for improvements.
1.2 REPORT OBJECTIVES
The major tasks and objectives of this engineering report as summarized in the Engineering
Agreement are:
o Determine the clearwell volume and configuration needed to satisfy the plants
disinfection and filter backwash requirements. Examine the use of the 250,000
gallon steel reservoir in this process.
o Evaluate the concrete in the sedimentation and flocculation basins to determine
the need for structural repair.
o Evaluate the requirements to rehabilitate the existing 1.5 million gallon
concrete reservoir.
o Examine the feasibility of lining the interior of the 4.0 million gallon steel
reservoir versus painting.
11 RECOMMENDED IMPROVEMENTS
Each of the improvements examined are outlined in more detail in the appendix of this report.
The series of memos included in the Appendix present the background data behind each
improvement. A summary of the improvements along with a recommended coarse of action
is included in this Executive Summary.
MR-- CLEARYaLL
Two clearwell options were evaluated, each satisfying the plants disinfection and backwash
storage requirements. Each option included use of the 250,000 gallon steel storage tank
located on the plant site. Both options have been sized to provide storage for two filter cell
backwash cycles (420,000 gallons) and sufficient chlorine contact time (131,000) to meet the
requirement of the Surface Water Treatment Rule (SWTR) as seasonal peak flows reach 10
million gallons/day.
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Option 1
Option 1 utilizes the existing 250,000 gallon steel tank for backwash water supply storage
only. To properly backwash both filters requires approximately 420,000 gallons. A new,
fully baffled 350,000 gallon concrete tank would be constructed for the dual purpose of
providing additional backwash supply storage and to provide chlorine contact time. The
concrete tank and steel tank together comprise the plant clearwell.
Low lift pumps will be required to transport filtered water from the filters into the new
concrete clearwell. The plant's existing high service pumps will draw suction by gravity flow
from the new concrete tank The steel tank would be filled by the high service pumps,
eliminating the existing transfer pumps. Backwash supply pumps would be provided at the
new concrete clearwell.
Option 2
Option 2 utilizes the existing 250,000 gallon steel tank in a different role. Under Option 2 all
of the plant flow would be pumped into the tank, requiring the use of transfer pumps similar
to current practice. However, the steel tank would be retrofitted with baffles so that it would
be the primary source of chlorine contact time. The high service pumps would take suction
from the steel tank as in current practice. A new 350,000 gallon "unbaffled" concrete tank
would be constructed primarily for backwash storage and for a minor portion of the required
chlorine contact time. The need for low lift pumps and backwash supply pumps are the same
as in Option 1. Also as in Option 1, the new concrete tank and existing steel tank would
comprise the total plant clearwell.
Summary
Table 1 compares the differences in construction cost of the two clearwell options. Cost
items are those that are not common to both options. The cost shown are current as of
August 1995.
DESCRIPTION OPTION 1 OPTION 2
EXISTING TANK
MODIFICATIONS $20,000 $190,000
TRANSFER PUMP STATION N/A $50,000
NEW CLEARWELL 1$200,000 $180,000
TOTALS
CONTINGENCY @ 5%
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$220,000 $420,000
11000 21000
$231,000 $441,000
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Option 1 is substantially less costly to construct than Option 2 and it eliminates the operation
and maintenance costs associated with the existing transfer pumps. Option 1 is also less
complicated to operate because the chlorine contact time requirements are fully met in just
one chamber. There would be no need for the operations staff to calculate the combined CT
(mg/l - min) of two tanks during high flow or when direct filtration treatment is used.
Clear-well Option 1 is recommended based on the following:
o Lower construction cost.
o Reduced operations and maintenance due to the elimination of the transfer
pumps.
o Less complicated operation because the chlorine contact requirement is met
with one tank under anticipated conditions.
WTP - SEDIMENTATION AND FLOCCULATION BASINS
The existing concrete located in the sedimentation and flocculation basins have been both
visually inspected and photographed, and cored by Braun Intertec, to aid in determining the
extent of the required repairs. Based on this we have found the existing concrete to be
cracked, spalling, deteriorated and poorly sloped. Failing joints and delamination between
original concrete and later overlays is also evident from the coring.
Suggested repairs to the flocculation and settling basin structure have been prioritized and the
reconstruction cost estimated for each item of work as follows;
1. Settling Basin - Reinforce common wall between open & closed basins
$42,130
2. Flocc Basin - Re-build outflow
$10,620
3. Flocc Basin / Settling Basin - repair top of common wall
$28,280
4. Settling Basin - Resurface sloped walls
$24,980
5. Settling Basin - Resurface floor slab
$34,480
6. Flocc Basin - Remove and replace slimmer baffles
$10,000
7. Flocc Basin - Resurface floor slab
$19,940
8. Flocc Basin - Repair concrete wall at slide gates
$4,260
9. Flocc Basin / Settling Basin - Resurface common separation wall
$11,500
10. Settling Basin - Stabilize existing baffle walls
$9,420
11. Remove and Replace Hydraulic Devices
$20,000
TOTAL $215,610
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A more detailed itemization of these preliminary estimated costs is available in the technical
memo included in the Appendix.
Flocculation Basins
Because of the manner in which the walls have been restored and the degree of delaznination
or lack of bond between the new and the old concrete, another coating of concrete or
elastomeric material is not considered to be an economical method of repair since its service
life is expected to be short. The costs of repairs to the floc basins is $84,600, to remove the
basins and install new ones the cost would be approximately $131,000. Therefore, rather than
incur a relatively large cost of repair for a very limited "life" it may be better economically to
perform rather limited "spot" repairs until sufficient funds are available or to commit funds
now to totally replace the floc basins.
Unless complete replacement is completed, it is recommended that the skimmer baffles be
replaced and the outflow be rebuilt. The rest of the flocculation basin repair work should be
accomplished by spot repair. We feel that an overlay will be nothing more than a temporary
fix and the City of Laurel will be faced with the same problems that are evident now in a
relatively short period of time. The spot repairs should last long enough to allow for
replacement funding to become available. Total cost is estimated to be $25,400.
Sedimentation Basins
Methods of renovating and repairing the concrete surfaces of the sedimentation basins would
include (1) a cast-in-place concrete overlayment, (2) a pneumatically applied concrete
overlayment (shat-crete), or (3) a proprietary type elastomeric coating placed over the
existing slab after the existing cracks have been filled or repaired.
The following improvements to the sedimentation basins are recommended:
o Repair common wall between open and closed basins
o Resurface the floor slab.
o Resurface sloped walls.
o Repair top of common wall sed/floc.
The total cost of these proposed recommendations is $104,000.
CONCRETE RESERVOIR SUMMARY
The existing 1.5 million gallon reservoir is needed to accommodate the current needs of the
City for two reasons. The first is so the interior of the 4.0 million gallon steel storage tank
can be maintained both now and in the future. The second is to increase the water storage
capacity for the City of Laurel.
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Reservoir Interior
Three different methods of sealing the tank were evaluated. These methods include 1)
Applying shotcrete to the existing surface, 2) Installation of a hypolon liner, and 3) Applying
a Tnemec Series 264 coating to the existing surface. For more information on the specifics
of these three option please refer to the technical memorandum located in the Appendix of
this report.
The use of a liner material is a cost effective method of sealing off the reservoir from all
seepage. A liner material is an ideal solution for sealing off any cracks in the existing
concrete. Maintenance however can become costly, especially in colder climates. The cost of
this option is about $72,000.
As an alternative, shotcrete can be sprayed onto the existing surface of the reservoir thus
filling all of the existing voids and placing a new layer of concrete over the existing one. A
disadvantage to this method is that cracks may reappear and periodic maintenance of that
situation is required. The cost of using shotcrete to seal the reservoir will be approximately
$69,000.
A third alternative is to use a elastomeric coating called Tnemec Series 264, over the existing
concrete. The coating can be spayed on in 40-100 mill thicknesses and is ideal for use on
existing concrete where cracking and settling has become a problem. The cost of this work is
estimated to be $60,000, for a 50 mill layer.
MW recommends the Tnemec Series 264 coating be used to upgrade the interior of the
concrete reservoir. The construction cost of the three options are comparable. The advantage
that the Tnemec has over shotcrete is that the potential for cracks to surface is less likely
because of its elastic properties that allow it to move with the structure, without being
damaged. If the Tnemec 264 does develop a leak it is easily patched. A liner material is
more susceptible to damage caused by expansion and contraction during cold weather than the
Tnemec 264 is. The Tnemic 264 costs less than the other two options and is less likely to
require extensive maintenance, thus making it the best option for the modifications to the
reservoir interior.
Reservoir Roof
A cover is needed to keep direct sunlight from breaking down the chlorine, needed to keep
the water free from algae, and also to protect the reservoir from any animals or debris that
MaY enter it. Six different types of covers for the existing concrete reservoir have been
evaluated. Each is summarized below. A more detailed evaluation of each is provided in
the Appendix.
' It is estimated that a structural steel roof frame (painted steel open-web joist
girders and roof joists) and painted steel deck (zincalum, for added service
life) will cost about $105,000. This cost is assuming that the structural
integrity of the reservoir is such that it will support a steel roof. Costs may
increase if pilasters have to be installed to support the roof. An itemization
of the estimated preliminary is included in the Appendix. The service life of
a steel roof system before major repairs are needed, is 20 to 25 years.
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Concrete -
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High Density
Polyethylene -
Floating Ridge
Panels -
Fiberglass -
Aluminum
Framed -
A concrete roof system will provide a longer service life (say 40 to 50
years) before major repairs re necessary. However, its initial 'cost is
estimated to be about $150,000, and it is not likely that the existing concrete
in the reservoir will be able to support a heavy concrete roof system.
A third alternative is to install a single piece HDPE floating flexible liner to
cover the reservoir. This can be done for approximately $45,000 to $50,000,
but maintenance costs on this type of a cover will be significantly higher
and the cover may only last 15 years.
For a cost higher than that of a floating cover, $75,000 to $80,000 dollars, a
flexible rigid cover can be installed. This roofing is constructed of a number
of rigid panels and will raise and lower as the level in the tank changes.
This type of cover is relatively new and untested in this part of the country.
A fiberglass roof was also examined. The cost of a fiberglass roof is
$220,000, thus this option was not perused.
The installation of an aluminum framed roof with a fabric cover can be
installed at an initial cost of about $125,000. This system is easily installed
and even though it is light weight it possesses all of the necessary loading
characteristics that will be required. The material is guaranteed to last 12
years but can be expected to last about 18. The aluminum frame is
guaranteed for 25 years and can be expected to last much longer.
MMI recommends that an aluminum roof with a fabric encasement material be placed over
the concrete reservoir. This type of roof will allow periodic inspections of the interior. A
floating cover will not provide for that ability without removing and then reinstalling the
cover. Another consideration is that if the tank is drained during the winter months the
floating covers would have to support a snow load without any support from the bottom.
This could cause damage to the cover and frequent maintenance, or replacement is possible.
The steel roof has an initial installation cost lower than that of the aluminum framed roof.
However, looking at the extended life cost in the Appendix, the aluminum structure will be
less expensive over time. Another advantage to the aluminum structure is its light weight.
The steel and concrete roof structure will place significant weight on the existing reservoir.
This could become a problem due to the present deteriorated condition of the concrete.
STEEL RESERVOIR INTERIOR SUMMARY
Painting the interior of the steel reservoir is an activity that must take place due to the
deteriorated condition of the existing surface. The new surface can be expected to last 15-25
years before it needs to be resurfaced. This can be done at a cost of about $200,000.
If a liner is placed in the tank it will cost an additional $175,000 to $185,000, for an 80 mil
HPC liner, as a one-time painting of the tank interior should still be completed prior to liner
installation. An advantage to placing a liner inside a tank is that it will virtually eliminate all
future painting requirements, along with eliminating the chance for the tank to develop a leak.
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One disadvantage to a liner in a steel tank in a cold climate is that there is potential for ice
buildup to damage the liner extensively. This can lead to high maintenance costs.
When the up front cost of the installation of the liner is considered along with the colder
climate, and the potential for ice to damage the liner, it is not felt feasible for the City of
Laurel to install a liner in the water tank at this time.
NM also recommends that before the tank is painted, it is emptied and inspected by all
bidding contractors prior to the bid opening. Because the condition of the interior of the tank
is not known at this time the contractor must have the opportunity to bid on the actual
condition of the tank, to avoid any future cost disputes.
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