Res 151-2008 10/21/2008 RESOLUTION NO. J� - O
RESOLUTION OF THE CITY COUNCIL OF THE CITY OF WICHITA
FALLS, TEXAS, TO APPROVE CHANGE ORDER NO. 1 FOR THE
NORTH BASIN SANITARY SEWER INTERCEPTOR PROJECT (CWF
08-560-10) IN THE AMOUNT OF $174,681.0044-06; FINDING AND
DETERMINING THAT THE MEETING AT WHICH THE RESOLUTION
WAS PASSED WAS OPEN TO THE PUBLIC AS REQUIRED BY LAW.
WHEREAS, the City of Wichita Falls entered a unit price contract with Wright
Construction with the estimated total of $951,193.00; and
WHEREAS, Change Order No. 1 would add $174,681.00 to the contract for a
revised cost of $1,125,874.00 with no increase the contract calendar days as detailed in
the commentary; and
WHEREAS, the City staff has reviewed all aspects of Change Order No. 1, and
recommends its approval.
NOW THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY
OF WICHITA FALLS, TEXAS, THAT:
SECTION 1. Change Order No. 1 for the North Basin Sanitary Sewer Interceptor
Project, CWF 08-560-10 is hereby approved and the City Manager is authorized to
execute Change Order No. 1.
SECTION 2. It is hereby officially found and determined that the meeting at
which this resolution was passed was open to the public as required by law.
PASSED AND APPROVED this, the 21st day of October, 2008.
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M PRO TEM
TTEST:
City Clerk
CORNERSTONE
E N G I N E E R I N G
2406 Kell Boulevard
Wichita Falls, Texas 76309
Voice: 940.322.6450 Fax: 940.723.6006
October 9, 2008
Mr. Russell Schreiber, P.E.
Director of Public Works
City of Wichita Falls
1300 Seventh Street
Wichita Falls, Texas 76301
Re: CWF560-08-10 North Basin Sewer Interceptor Project
Verification of prices related to a proposed change in pipe type
Dear Mr. Schreiber:
In connection with bids received on September 25, 2008, I am recommending that we initiate a
change order to install a stronger sewer pipe on this Project. The pipe allowed by the Project
specifications carries a pipe stiffness rating ("PS") of 46. This is a somewhat flexible pipe which
is dependent upon adjoining soil conditions and upon proper placement and embedment
materials to support the overburden loads. For a shallower pipe installation there would be no
concern with this pipe, but our Project has depths of cut as deep as twenty feet. At those
depths, the more flexible pipe leaves little margin for unforeseen conditions in the excavation or
for any inconsistencies with the pipe installation. Additionally, City Detail No. 3030, Non-Load
Bearing Embedment Detail, which was used in the Project Documents appears to permit a
choice of pipe embedment materials and in the case of the PS 46 pipe, the embedment must
be an open graded aggregate. My recommendation therefore is to install a more rigid pipe SDR
26 pipe which has a PS 115 rating. I feel that it is the best interest of the City to use the more
substantial pipe. This will provide for a longer service life and it will significantly reduce the
potential for future maintenance issues.
I regret that I didn't come to this conclusion in sufficient time to issue an addendum prior to the
bid date. The Project would then have been bid with the stiffer pipe and a change order for a
change in pipe material would be unnecessary. However, the bidding process did establish an
acceptable low bidder, Wright Construction Co., Inc. ("Wright") of Grapevine. While I have not
had first hand experience with this contractor, I did receive positive references from three
different sources as to Wright's reputation and past performance.
I requested that Wright obtain and provide to us the cost involved to upgrade to the more
substantial SDR 26 pipe. Wright has provided us with the increase in cost to change to the
stronger pipe along with their supplier's quotes to justify their cost differential. The requested
change order amount is an increase of $174,681.00. This amount is stated to include the
differential in pipe cost, a markup of 4.48% for overhead and profit, and the cost of the
corresponding increase in cost for the payment and maintenance bond required for the Project.
I called several contractors and suppliers in an effort to verify that the increase requested by
Wright was reasonably related to the increase in pipe cost. I discovered that there are
considerable variations in the prices quoted by different suppliers. PVC pipe is a petroleum
based product and some of the price variation could certainly be related to current economic
events and market uncertainty. Prices could have even changed since earlier this week given
the stock market's performance over the last several days. It also stands to reason that prices
would vary by supplier based on current inventories.
The pipe sizes to be installed on this Project range from 18 inches to 30 inches in diameter. As
to the PS 46 pipe which was originally bid, I obtained three different pipe quotes that ranged
from a low of $97,198.53 to a high of $139,645.44. Wright stated that a pipe price of
$107,221.01 was used for their original bid. This is in the lower end of the range of the quotes I
received.
For the stronger SDR 26 pipe, yesterday a local supplier gave me a price of $251, 427.93. A
manufacturer's representative in the Metroplex, gave me prices that were lower for the smaller
diameters involved but higher for the 30 inch diameter pipe. Wright's total for this pipe is
$271,237.98 which is 7.9% higher than the price I obtained.
Given this information, it seems that while the change order amount requested by Wright
Construction may not reflect the absolute lowest pipe price available, Wright's requested
amount is reasonable and has been documented. Therefore, it is my recommendation that
along with the bid award to Wright Construction Co. Inc. we also accept an initial change order
in the amount of $174,681.00 to install SDR 26 PVC pipe on the Project.
Please call with any questions or comments. Thank you for the opportunity to work with the City
on this Project!
Sincerely,
PROVEN CORNERSTONE ENGINEERING, PLLC
dba Cornerstone Engineering
By:Original signed by Martin I,itteken, Jr.
Martin Litteken, Jr., P.E., President
MFL/me
xc: Teresa Rose, P.E., Project Manager
WO File 070037
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Martin Litteken, P.E.
2406 Keil Bivd.
Wichita Falts,Tx. 76309
RE: NORTH BASIN SANITARY SEWER INTERCEPTOR
PROJEC7 NO. CWF08-560-10
Mr. Litteken,
This letter is to inform you of the price increase to change the sanitary sewer pipe stiffness, from a
minimum of 4b to a minimum of 115, on the 1S", 21", 24" and 30"pipe. The totaf increase wilE be
$174,681.00. This is inclusive of the additional bond cost.
Please mntact me if any additionai information is needed.
Sincerely,
�
�_ N.,,�,�..�
Greg Spears
Project Manager
Wright C:onstruction Co., inc.
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