HomeMy WebLinkAboutStaff Report 3.G 11/07/2005CITY OF PETALUMA, CALIFORNIA
AGENDA BILL
3.G
November 7, 2005
Aeenda Title: Resolution Awarding a Construction Contract for the Meetine Date: November 7, 2005
2005 Oxidation Pond I Dike Repair Project
Meeting Time: ® 3:00 PM
❑ 7:00 PM
Cateeory (check one): ® Consent Calendar ❑ Public Hearing ❑ New Business
❑ Unfinished Business ❑ Presentation
Denartment: Director: Contact Person: Phone Number:
Water Resources & Michael Ban, P.E. Margaret Orr, P.E. 778-4304
Conservation
Cost of Prouosal: $373,000 r r Account Number:
8299-54151-C500405
Amount Budgeted: The amount budgeted is $638,000. Name of Fund: Wastewater Funds
Expenditures of $238,393.97 in FY 04-05 leave a remaining budget
of $403,606.03, which is above the cost of the project.
Attachments to Aeenda Packet Item:
Proposed Resolution Awarding the Construction Contract
Pictures Pond 1 Plant Growth (Exhibit A)
Location Map (Exhibit B)
Summary Statement: The oxidation ponds are an important unit operation providing secondary treatment
for wastewater flows greater than 4 million gallons per day. Portions of the dike surrounding Oxidation
Pond No. 1 have severely eroded since the oxidation ponds were originally constructed in 1972. This
project will repair and protect the dike. The City received seven (7) bids for the 2005 Oxidation Pond 1
Dike Repair Project ranging from $283,840 to $406,100 on September 29, 2005.
Recommended Citv Council Action/Sueeested Motion: City Management recommends that the City
Council adopt the resolution awarding the contract to the low bidder, Ghilotti Construction Company. The
work is scheduled to begin in December and is expected to be completed by the end o/fJury 2006.
.
Reviewed by Admin. Svc. Dir: Reviewed by�ity Attorney: Approved by Clty Manager:
D't) (d (SLS ) te: )((,,,V—Date: x'45
Todav's Date: Revision # and Date Revised: File Code: SAC.I.P. Folder\WASTEWATER
10/21/05 #1, 10/25/05 Folder\C500405 - 2005 Oxidation Pond Dike
Repair\Award Agenda Bill and CC Report II -7-05
(FINAL).doc
CITY OF PETALUMA, CALIFORNIA
NOVEMBER 7, 2005
FOR
RESOLUTION AWARDING A CONSTRUCTION CONTRACT FOR THE 2005
OXIDATION POND 1 DIKE REPAIR PROJECT
PROJECT NO. C500405
EXECUTIVE SUMMARY:
The oxidation ponds are an important unit operation providing secondary treatment for
wastewater flows greater than 4 million gallons per day. Portions of the dike surrounding
Oxidation Pond No. 1 have severely eroded since the oxidation ponds were originally
constructed in 1972. This project will repair and protect the dike. The City received seven (7)
bids for the 2005 Oxidation Pond 1 Dike Repair Project ranging from $283,840 to $406,100 on
September 29, 2005.
City Management recommends that the City Council adopt the resolution awarding the contract
to the low bidder, Ghilotti Construction Company. The work is scheduled to begin in December
and is expected to be completed by the end of January 2006.
2. BACKGROUND:
Treatment of Petaluma's wastewater occurs at two locations: 950 Hopper Street and at the
oxidation ponds. All wastewater in Petaluma is first pumped to the 950 Hopper Street
wastewater plant. The wastewater plant on Hopper Street provides primary treatment for up to 6
million gallons per day (mgd) of incoming wastewater and secondary treatment for 4 mgd of
wastewater. Because of diurnal flow changes, influent flows can exceed 6 mgd. When the flow
into the plant exceeds the capacity of the Hopper Street facility the remaining raw wastewater
and primary treated water is sent to the oxidation ponds for secondary treatment and disinfection
prior to reuse or disposal. At the oxidation ponds, during the wet season, the wastewater is
typically split between the aerated lagoon and Pond No. 1. During the dry season the wastewater
is sent to the aerated lagoon and then to Pond 1.
Since utilization of the ponds began in 1976, biosolids have grown in the aerated lagoon and
Pond No. 1 to degrade the incoming wastewater that was not fully treated at Hopper Street. Last
summer the Department of Water Resources surveyed the biosolids in the aerated lagoon and
Pond No. 1, and determined the aerated lagoon and Pond 1 were nearly full of biosolids.
Biosolids were also stored on the dikes between Pond 1 and Pond 4. The biosolids stored on the
dike were removed last fall in the Phase I Biosolids Removal Project. The presence of such a
great volume of biosolids in Pond 1 diminished the treatment capacity and made it impossible to
pull down the water level in the Pond 1 for dike repairs. If the water level was lowered with the
volume of biosolids present in Pond 1, severe odors could have resulted. Hence, the removal of
' Petaluma's NPDES discharge permit recognizes that treatment occurs in this manner. In the early 1970s the City
was prohibited by the Regional Water Quality Control Board from expanding the treatment capacity of the Hopper
Street plant. Instead, the oxidation ponds were constructed.
the biosolids from Pond 1 began in August of 2005 and is scheduled to be complete by
November 19, 2005 (Phase II Biosolids Removal Project). The biosolids are being removed with
a water cap in place to keep odors under control. The presence of biosolids on the dike caused
excessive plant growth in some areas of the dike and pond bottom (Exhibit A). These plants
must be removed in order to maintain the treatment capacity of the ponds, to repair the dike
walls, and to allow placement of aeration equipment anticipated this winter as part of the Ellis
Creek Water Recycling Facility Project. The new Ellis Creek aeration equipment requires
rip/rap placement below and around the devices to maintain the integrity of the pond in the area
where substantial mixing intensity is imparted. The Regional Water Quality Control Board may
grant the City some new capacity when these aerators are placed which will help the City to meet
capacity needs while the new plant is being constructed.
To effect treatment during the biosolids removal project in Pond 1, several aerators from Pond 1
were moved to Pond 4. Aerators were purchased as part of the Aeration Project this past spring.
The new aerators from that project will be placed in Pond 1 by the Ellis Creek General
Contractor. The Ellis Creek General Contractor will add electrical conduit and associated gear to
allow all the aeration equipment to be functional at the oxidation ponds by May 1, 2005. The use
of all the aeration equipment to supply oxygen to microbes that eat the waste in the water as food
will allow the Regional Water Quality Control Board the ability to grant an increase in Average
Dry Weather Flow Capacity as in interim increase step until the new Ellis Creek Water
Recycling Facility comes on-line in early 2009. Long-term the aerators will be used during high
flow events.
Portions of the dikes surrounding the oxidation ponds were originally constructed without any
erosion protection (rip/rap). The Department of Water Resources and Conservation began a
systematic program to repair and protect the dikes in 1997. Since that time, dikes surrounding
Oxidation Pond Nos. 2,3,4,5,6,8,9 have been repaired or partially protected. Oxidation Pond
No. 1 requires repair to the dike due to excessive plant growth due to the biosolids storage on the
levy and erosion. The project involves removing plant material, placing and compacting eroded
dike material, and adding riprap for erosion protection from wind and aeration equipment around
Oxidation Pond No. 1 and under the location of the aerators (see Exhibit B for location map).
The Department of Water Resources and Conservation prepared the plans and specifications for
this project. The Notice Inviting Bids was issued on August 29, 2005. Bids were received and
opened on September 29, 2005. The following is a summary of the bids received:
NAME OF BIDDER
Ghilotti Construction Company, Santa Rosa, CA
Goebel Paving, Grading & Underground, Inc., Petaluma, CA
Ghilotti Brothers, Inc., San Rafael, CA
North Bay Construction Inc., Petaluma, CA
Maggiora & Ghilotti Inc., San Rafael, CA
Granite Construction Co., Healdsburg, CA
HRS Inc., Santa Clara, CA
The engineer's estimate for construction is $289,000.
BID AMOUNT
$283,840.00
$292,545.00
$317,420.00
$333,220.00
$350,660.00
$353,800.00
$406,100.00
With a bid of $283,840, the apparent low bidder is Ghilotti Construction Company. This bid
amount is below the engineer's estimate of $289,000. Ghilotti Construction Company
satisfactorily completed two projects for the City's Public Works Department and two projects
for the City of Novato within the last two years. Staff verified that Ghilotti possesses a valid
Class A California Contractor's license, license number 644515, expiration date May 31, 2006,
that qualifies Ghilotti to perform the work.
ALTERNATIVES:
1. Award the contract to the low bidder.
2. Reject all bids and re -advertise.
3. Take no action
4. FINANCIAL IMPACTS:
The total remaining budget for this project is $403,606.03 as shown in Table 1.
Table 1
Project Budget
Item
Cost
FY 04-05 Appropriation
$404,000
FY 05-06 Appropriation
238,000
Total Appropriation through FY 05-06
$642,000.00
FY 04-05 Expenditures
($238,393.97)
Remaining Budget
$403,606.03
As shown in Table 2, the total estimated costs for the project, including General Fund, are
$373,000. This amount is below the remaining budget of $403,606.03.
Table 2
Estimated Construction Costs
Item Cost
Construction Contract (low bid) 283,840
Administration/Inspection/Testing 20,000
Project Contingency 51,000
Subtotal 354,840
General Fund
Total
CONCLUSION:
17,742
$372,582, Say $373,000
Following the award, the contractor will enter a contract with the City and submit the required
contract documents, bonds and insurance.
4
6. OUTCOMES OR PERFORMANCE MEASUREMENTS THAT WILL IDENTIFY SUCCESS OR
COMPLETION:
Completion of the construction.
RECOMMENDATION:
City Management recommends that the City Council adopt the resolution awarding the contract
to the low bidder, Ghilotti Construction Company. The work is scheduled to begin in December
and is expected to be completed by the end of January 2006.
1
3 AWARDING A CONSTRUCTION CONTRACT FOR THE 2005 OXIDATION POND 1
4 D1I(E REPAIR PROJECT
5 PROJECT NO. C500405
6
7 WHEREAS, the dike at oxidation Pond 1 requires repair due to erosion and plant removal due
8 to biosolids;
9
10 WHEREAS, in accordance with the City of Petaluma Charter and Municipal Code, California
11 Public Contract Code Section 20162 and other applicable law, the City of Petaluma solicited bids
12 for the Project; and
13
14 WHERAS, the engineer's estimate for the Project is $289,000; and
15
16 WHEREAS, seven (7) bids for the Project were received on September 29, 2005, and opened in
17 accordance with California Public Contract Code Section 4105.5 and other applicable law; and
18
19 WHEREAS, the apparent low bid for the Project was submitted by Ghilotti Construction
20 Company, in the amount of $283,840; and
21
22 WHEREAS, the City staff has verified that Ghilotti possesses a valid California Contractor's
23 license, Class A, license number 644515, expiration date May 31, 2006, that qualifies Ghilotti to
24 perform the Project; and
25
26 BE IT RESOLVED by the Petaluma City Council that:
27 1. The low bid is accepted.
28 2. The contract is hereby awarded to Ghilotti Construction Company, 246 Ghilotti Avenue,
29 CA 95407, the low bidder.
30 3. This resolution shall become effective immediately.
31 4. The City Manager is hereby authorized and directed to sign the Project Agreement on
32 behalf of the City of Petaluma.
3
1
2 5. The Director of Water Resources and Conservation is hereby delegated authority to
3 execute Project changes up to the contingency amount of $51,000.
4 6. All portions of this Resolution are severable. Should any individual component of this
5 Resolution be adjudged to be invalid and unenforceable by a body of competent
6 jurisdiction, then the remaining Resolution portions shall be and continue in full force
7 and effect, except as to those Resolution portions that have been adjudged invalid. The
8 City Council of the City of Petaluma hereby declares that it would have adopted this
9 Resolution and each section, subsection, clause, sentence, phrase and other portion
10 hereof, irrespective of the fact that one or more section subsection, clause sentence,
11 phrase or other portion may be held invalid or unconstitutional.
12
13
14
15
16
7
EXHIBIT A
PICTURES OF EXCESSIVE PLANT GROWTH
AT OXIDATION POND 1
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EXHIBIT B
LOCATION MAP
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