HomeMy WebLinkAboutItem 09 - Water Treatment Plant and Hilton Lift StationMEMO TO:
FROM:
MEETING DATE:
SUBJECT:
RECOMMENDATION:
HONORABLE MAYOR AND MEMBERS OF THE CITY COUNCIL
ROGER NELSON, CITY MANAGER
MARCH 15, 2005
WATER TREATMENT PLANT AND HILTON LIFT STATION
IMPROVEMENTS - CHANGE ORDER # 1
City Council to consider approving Change Order # 1 in the amount of ,$ 58,845.00 and
three additional working days to address scope changes requested by the City,
authorize the Staff to execute said change order, and take any necessary action.
FUNDING SOURCE:
09
Contingency
TOTAL
BACKGROUND:
Amount Award Percent
$ 352,450.00 12.0%
$ 2,440,845.00 $ 58,845.00 83.2%
$ - 0.0%
$ 141,155.00 4.8%
$ 2,934,450.00 $ 58,845.00 100.0%
The Water Treatment Plant and Hilton Lift Station require enlarged facilities to keep up
with demand created by growth in the Grapevine Utility System. The Water Treatment
Plant Expansion has begun construction of the 1.4 MG ground storage tank ring beam
foundation and yard piping and piping modifications for the new high service vertical
March 8, 2005 (3:30PM)
01 Utility Bonds
20048940 -534 -7 -000003 -SW
$ 160,000.00
5.5%
95 Utility Bonds
20048930 -534 -1 -000018 -WA
$ 194,750-00
6.6%
99 Utility Bonds
2OG48930-534-5-0"16-WA
$ 285,079.00
9.7%
01 Utility Bonds
200 -48930 -534 -7 -000009 -WA
$ 1,395,884-00
47.6%
01 Utility Bonds
20048930 -534 -7 -000010 -WA
$ 898,737-00 $
58,845-00 30.6%
09
Contingency
TOTAL
BACKGROUND:
Amount Award Percent
$ 352,450.00 12.0%
$ 2,440,845.00 $ 58,845.00 83.2%
$ - 0.0%
$ 141,155.00 4.8%
$ 2,934,450.00 $ 58,845.00 100.0%
The Water Treatment Plant and Hilton Lift Station require enlarged facilities to keep up
with demand created by growth in the Grapevine Utility System. The Water Treatment
Plant Expansion has begun construction of the 1.4 MG ground storage tank ring beam
foundation and yard piping and piping modifications for the new high service vertical
March 8, 2005 (3:30PM)
turbine pumps located outside and the high service horizontal centrifugal pumps located
in the filter gallery basement. Items addressed in Change Order #1 will both correct
problems encountered during construction and address urgent plant repairs that are
advantageous to pursue during the current construction activities. A brief description of
each item is listed below.
Item One
Modifications to existing 36" yard piping are needed for additional fittings. The plans
showed a "wye" fitting which was determined not to exist after the area around the fitting
was uncovered. A new fitting will be added to connect the existing yard piping to the
new yard piping for the new ground storage tank at a cost of $3,709.00. One additional
working day will be added to the contract time to install the extra fitting and yard piping.
Item Two
A new Caustic Soda Tank is proposed to replace the existing tank because of severe
cracking of the existing tank. Caustic soda is a highly corrosive chemical that requires
special handling and storage. The existing tank has already been refurbished once but
the repairs were inadequate to prevent further cracking and leakage. The existing tank
currently cannot be filled to its normal level without leaking. The new tank was not part
of the original scope of the construction contract. The replacement was added to the
scope of the change order to expedite the replacement before heavy water demand
creates operational problems with chemical storage. The total cost of replacing the tank
is $38,643.00. One additional working day will be added to the contract time to install the
new tank.
Item Three
Additional thrust blocks are proposed for the piping in the filter gallery basement to
provide an added factor of safety against a failure of the existing piping inside the
building. The additional thrust blocking will ensure that the existing piping will not fail
causing a flooding condition in the filter gallery basement with the potential to shutdown
the water plant. The total cost of this item is $1,148.00.
Item Four
A new 20" gate valve is proposed to replace a non -working 20" butterfly valve located on
the discharge header for the high service pumps. The existing 20" butterfly valve was
discovered to be non -working during a plant shutdown for new connections to the
existing discharge header. This condition caused other valves outside the plant to be
closed in order to isolate the 20" water main and resulted in a labor intensive and
lengthy operation to dewater and then pressure up the 20" water line. The total cost of
the valve replacement is $13,458.00. One additional working day will be added to the
contract time to install the new valve.
March 8, 2005 (3:16PM)
Item Five
The tank ring beam design will be modified from the original 5' beam depth to a revised
4' beam depth. The revised depth is acceptable since solid rock was encountered
providing an excellent foundation bearing capacity without additional excavation. The
total credit for this change in the design is <$709,00>.
Item Six
Additional fittings for the vertical turbine pump discharge line are needed to compensate
for an elevation difference between the plans and the actual elevation of the existing
discharge header. Because the header is buried this condition was not known until the
area around the discharge header was uncovered. The total cost for the additional
fittings is $2,596.00.
Staff recommends approval of Change Order #1
IM0.1
March 8, 2005 (3:15PM)
rion
FREESE - NICHOLS
CHANGE ORDER (4.43)
PROJECT: Grapevine Water Treatment Plant and Hilton Lift Station Improvements
PROJECT NUMBER
OWNER: City of Grapevine
GPV 04220
CONTRACTOR: Cooper General Contractors
ENGINEER: Freese and Nichols, Inc.
CHANGE ORDER NO.: One DATE:
4 -Mar -05
Make the following additions, modifications or deletions to the work described in the
Contract
Documents:
1) Modify 36" FW Line as described on attached PCM -001 -revised.
$ 3,709.00
2) Provide and install new Caustic Soda Tank as per attached PCM -002
$ 38,643.00
3) Provide thrust blocks on existing piping as per attached PCM -003
$ 1,148.00
4) Replace existing 20" BF Valve with new 20" GV as per attached PCM -004
$ 13,458.00
5) Modify ring beam for GST as per attached CMR -002
$ (709.00)
6) Provide elbows to align piping to new pumps as per attached CMR -004
$ 2,596.00
Total this change order
$ 58,845.00
The compensation agreed upon in this Change Order is full, complete and final payment for all costs the
Contractor may incur as a result of or relating to this change whether said costs are known, unknown,
foreseen or unforseen at this time, including without limitation, any cost for delay, extended overhead,
ripple or impact cost, or any other effect on changed or unchanged work as a result of this Change
Order.
Original Contract Amount $
2,382,000.00
Previously Approved Change Order Amount $
-
Adjusted Contract Amount $
2,382,000.00
Proposed Change Order Amount $
58,845.00
Revised Contract Amount $
2,440,845.00
Previous Contract Time
330 days
Previous Substantial Completion Date
N/A
Previous Final Completion Date
December 8, 2005
Net Change in Contract Time
3 days
Revised Contract Time
333 days
Revised Substantial Completion Date
N/A
Revised Final Completion Date
December 11, 2005
Recommended by Approved by
FREESE AND NICHOLS, INC. Cooper General Contractors
By Z�� 3 -{ o By
ate
Date
Approved by
City of Grapevine
By
Date