1l. Inspection Murray Hill Water Tower 1 " - ' / i •
CITY O -----
i . CHANHASSEN
i .. 690 COULTER DRIVE • P.O. BOX 147 • CHANHASSEN, MINNESOTA 55317
I . ' (612) 937-1900 • FAX (612) 937-5739
Action by Ctry Adrn#ith:7eso,
b1EhiORANDUI�i irdcrd U."' blal
ITO: Don Ashworth, City Manager Reiss �-��
I .,Date Sub n:Ted to .Km
FROM: Gary Warren, City Engineer
DATE: February 7, 1990 Date s r .y . �o cc:r
IISUBJ: Accept Inspection Report for Murray Hill Water Tower and
Authorize Preparation of Rehabilitation Plans and
Specifications, Improvement Project No. 89-24
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On November 8, 1989, the City's consultant, AEC, inspected our 200,000 gallon
I pedestal water storage tank located off of Murray Hill Road. Similar to the
downtown storage tank, an inspection report was completed and recommendations
made for upgrading and painting this storage tank. Attached are the summary and
II recommendations from this report for your information. The full report is
available for review in the Engineering Department. As noted therein, AEC has
estimated the total cost of repairs and painting to be approximately $100,300.
This does not include the cost of security fencing around the tower which the
I City would contract separately for. The tank was constructed in 1973 and has
not been painted or rehabilitated since.
1 This project was budgeted in the 1990 Water Expansion Capital Project Fund (No.
402) at $120,000 (see Attachment No. 2).
It is desirable to have the plans and specifications for the repairs and
painting prepared at this time such that bids can be taken in the near future.
The actual work, which is estimated to take five weeks, will be scheduled with
the low bidder for some time outside of the City's peak water consumption months
I since the tower obviously will be taken out of service for these repairs. Most
likely we will be looking at a September/October timeframe for the actual
repairs to be done unless the low bidder is able to complete this work before
II July.
It is therefore recamtended that the City accept the inspection report as pre-
pII ared by AEC Engineers & Designers and that AEC be authorized to prepared the
rehabilitation plans and specifications for the City.
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IAttachments: 1. Inspection Report summary and recommendations.
2. Fund 402 Capital Project Fund.
IIc: Jack Kollmer, AEC
Jerry Boucher, Utility Superintendent
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' INTERIOR AND EXTERIOR INSPECTION REPORT
200, 000 GALLON (200 MG) PEDESTAL SPHEROID
MURRAY HILL TOWER
CITY OF CHANHASSEN, MN
' AEC PROJECT NO. MN 901
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BY
AEC - ENGINEERS AND DESIGNERS
511 ELEVENTH AVENUE SOUTH
MINNEAPOLIS, MN 55415
TELEPHONE: 612-332-8905
CITY OF GHA DkSSEM
P i4
JAN 15 1999
ENGINEERING DEPT.
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AEC
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511 Eleventh Avenue South
AEC - ENGINEERS & DESIGNERS Minneapolis, Minnesota 55415
612/332-8905
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ELEVATED WATER TANK INSPECTION - No. MN 901
Client: City of Chanhassen
Contact Person: Jerry Boucher I
Telephone: 612/474-2086
Tank Description: 200 MG Pedestal Spheroid I
Tank Location: Behind Minnetonka Jr . H.S.
Type of Coatings: Interior: Zinc I
Exterior : Alkyd
Inspected by: Robert E. Kollmer
Date of Inspection: November 8, 1989 '
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1 .0 SUMMARY
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It appears that the tank was last coated in 1973. The coating
is in poor condition and is non-repairable. The tank requires
a complete new interior and exterior coating. II
Structurally, the tank is sound . However, various structural II modifications such as additional vents, manways and
miscellaneous repairs are recommended .
It is estimated that the complete recoating plus the
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recommended modifications and repairs will cost approximately
$100, 300.00 and take 5 weeks to complete .
These cost estimates represent the current pricing structure . I
If you plan to proceed with the coating of this tank, the
sooner the specifications are ready for bidding , the more
competitive the bids will be .
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The tank painting should be first inspected within the warranty
period, and every three years thereafter.
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In our opinion, if all the recommendations are followed and the
tank is inspected regularly, the new coating should last 15 to
I20 years with only minor repairs. With proper maintenance, the
tank will provide many years of service.
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Branch Office: 13807 Village Mill Drive • Midlothian,Virginia 23113 • 804/379-3944 1
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City of Chanhassen
AEC Project No. MN 901
I2 .0 RECOMMENDATIONS
I The photographs referred to in this section are in Appendix A.
All drawings are found in Appendix B. The surface preparation
requirements for all repairs or new welding are described in
IAppendix C.
2.1 Interior Structural
I2 .1.1 Weld the unwelded interior seams on the two roof
manways . See photo 2 .
I2 .1.2 Weld the interior seam on the 3 x 3 ft. square, roof
erection patch plate . See photo 3.
I2 .1.3 Weld the eight (8) partially unwelded vertical butt
seams on the top 2 feet of the shell torus section.
This area is above the High Water Level (HWL) and
Iadjacent to the roof . See photo 4.
2 .1.4 Remove the eight (8) shell erection angles by air arc
II gouging or cutting torch. Repair surface by welding
or grinding in accordance with Appendix C. See
photos 5 and 6.
I2 .1.5 Seal weld the intermittently welded stiffner rings on
the dry well tube. There are four (4) such stiffners
located below the High Water Level (HWL) . Refer to
Iphoto 7.
2 .1.6 Remove all erection bracket scab marks below the High
I Water Level (HWL) by air arc gouging , cutting torch,
or grinding. There are approximately 100 erection
bracket scab marks. Repair the tank surface by
Iwelding or grinding in accordance with Appendix C.
2 .1. 7 Remove the existing interior reservoir ladder , on the
dry well tube . See photos 2 and 8.
I2 .1 .8 Replace the 18 inch round manhole gasket in the tank
bowl. See photo 14.
I2 .1.9 Add a "T" handle wrench to the drain plug in the tank
bowl. This will facilitate opening the drain when
Icleaning the tank. See photos 8 and 9.
I AEC
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City of Chanhassen
AEC Project No. MN 901
2.1.10 Photo No. 8 indicates that the top of the drywall I
tube is not connected to the top of the tank. This
is not the normal practice as it introduces high II stresses in the base of the tube. We recommend that
the tower manufacturer be contacted and methods of
attaching the tube to the tank roof be discussed .
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2.2 Interior Wet Coating
2.2.1 After all structural repairs are completed, the I
entire tank surface should be abrasive blasted and
coated with a light colored polymide epoxy system, II similar to Tnemec Series 20 Pota-Pox Epoxy .
2.2.2 For examples of current conditions and coating
failures see photos 2 through 11.
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2.2.3 Interior Dry Coating
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2.2.4 The interior dry coating is in poor condition.
Because of the age, and lack of intercoat adhesion, II the coating is non-repairable and needs complete
replacement with an epoxy coating system. See photos
12, 13 and 14.
2.3 Exterior Structural
2.3 .1 Install one (1) 24-inch round, AWWA hinged I
ventilation roof manway, approximately 180 degrees
from the existing manway. This manway will provide
additional ventilation during the interior surface
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preparation and coating . For a typical manway, see
AEC Standard Drawing .
2.3.2 Replace the tank vent/finial with a removable top '
mushroom vent, similar to the AEC Standard Drawing in
Appendix B. The new vent and vent screen design
should meet AWWA D100 and local Health Department II Regulations. The removable top will improve
ventilation and allow access to the tank interior
during reconditioning . The existing vent does not
Imeet tight roof. See photo 15.
2 .3 .3 Replace the overflow pipe screens to prevent birds
and insects from entering the reservoir . Use a
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corrosion resistant, heavy-gauge screen with a mesh
size no smaller than 1/4 inch square opening . See
photo 16.
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AEC
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City of Chanhassen
AEC Project No. MN 901
2 .3.4 Install a concrete splash pad under the existing
overflow pipe. See photo 16.
2.3.5 To prevent tower base plate corrosion from trapped
soil moisture, lower the existing ground grade around
the water tower so that the foundation is at least 4
' to 6 inches above grade level. See photos 17, 18 and
20.
2.3.6 Repair damaged anchor bolt chair by welding. See
photo 18.
2 .3 .7 Install a 8-12 foot high chain link fence with
anti-climb device, around the reservoir to prevent
access and vandalism by unauthorized personnel. See
photo 17.
' 2 .3.8 Remove insulation on inlet piping and abrasive blast
and epoxy coat exterior of piping from valve pit to
' the reservoir bowl. Reinstall insulation. See
photos 21 through 24.
' 2 .4 Exterior Coating
2.4.1 Due to age, chalking, deterioration, lack of
' intercoat adhesion, and lack of resistance to
mechanical damage (rocks) and graffiti , the entire
exterior coating should be removed and replaced with
' an epoxy/urethane coating system, similar to those
manufactured by the Tnemec company. See photos 15
through 20.
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AEC
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City of Chanhassen
AEC Project No. MN 901
3.0 ENGINEERING COST ESTIMATES
3.1 Interior structural repairs $ 8, 300.00
3.2 Interior coatings wet and dry
Type of coating - epoxy system $ 33, 250.00 '
3.3 Exterior structural repairs $ 10, 650.00
(excludes grading and fence)
3.4 Exterior coating
Type of coating - epoxy/urethane
system $ 30, 500.00 '
3.5 Logo and Lettering $ 3, 600.00
3.6 Engineering specifications and '
inspection fee $ 14, 000.00
3.7 Estimated Total Cost $ 100, 300.00 '
3.8 Estimated job duration: Five weeks.
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Report submitted :y
AEC - ENGINEERS AND DESIGNERS '
t/0'4
John R. Buzek, P.E.
President
� . I/info
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Enclosures - Field Inspection Report
Appendix A
Appendix B
Appendix C
1546M
AEC
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I AEC - ENGINEERS & DESIGNERS 511 Eleventh Avenue South
Minneapolis, Minnesota 55415
ELEVATED WATER TANK INSPECTION REPORT 612/332-8905
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SECTION I--DESCRIPTION
IPROJECT NO. MN901
DATE OF INSPECTION November 8, 1989
IAEC INSPECTORS 1) R. Kollmer 2) S. Mulhern
' TANK OWNER City of Chanhassen
OWNER'S CONTACT Jerry Boucher, Utility Sup.
ITANK LOCATION: Street/City/State Behind Minnetonka Jr. High Sch
TANK DESIGNATION Murray Hill
ITYPE OF TANK Spheroid - single pedestal
IMANUFACTURER AND CONTRACT NO. P.D.M. No. 22703
CONSTRUCTION DRAWINGS AVAILABLE No
IYEAR BUILT 1973
CAPACITY 200,000 gallon (200 MG. )
ITYPE OF CONSTRUCTION: Welded Yes Riveted
INUMBER OF SUPPORT COLUMNS One - dry riser
RESERVOIR DIAMETER 40 ft .
IHEIGHT: Overall 137 '+/- Balcony N/A
HEIGHT TO: H.W.L. 132 ft . L.W.L . 102 ft
' TYPE OF ACCESS TO TANK INTERIOR Ladder in dry riser
IEXISTING COATING INFORMATION
INTERIOR EXTERIOR
IDATE LAST COATED 1973 1973
COATING CONTRACTOR Unknown Unknown
ISURFACE PREPARATION Unknown Unknown
PAINT SYSTEM Zinc Alkyd
IPAINT MANUFACTURER Unknown Unknown
1 Branch Office: 13807 Village Mill Drive • Midlothian,Virginia 23113 • 804/379-3944
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' ` FUND: 402 WATER EXPANSION
FUNCTION: CAPITAL PROJECT FUND I
1990 BUDGET
. Mary I
This fund derives its money from water hook-up charges and is dedicated to pay
Ioversizing and other general benefit costs associated with the water utility
system. Revenue into this fund fluctuates greatly in that collections are
based on development in areas where trunk costs were not assessed as part of
the construction II project.
FIVE YEAR CAPITAL IMPROVEMENT PROGRAM
FOR THE O-W4+ASSEN WATER SYSTEM
ESTIMATED II
YEAR DESCRIPTION COST
1989 Painting and general repair of West 76th Street
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water tower 75,000
Remove pumps and liner at well #4 and
overhaul/repair as necessary 25,000 II
Construct Lake Lucy Road Trunk Watermain 100,000*
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Modify Well #3 to increase capacity 50,000
General Repairs 10.000 I
260,000
1990 County Road 17 Watermain 60,000 I
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Blower & grates for chlorine rooms 15,000
Auxiliary Pump for Booster Station 20,000 I
Painting and general repair of Murray Hill 411114---------11*. Water tower 120,000 '
Consumption telemetry sump system to monitor all
, operations of wells & reservoirs. 30,000
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General Repairs 30.000
275,000
1991 Remove pumps and liner at well #2 and 11
overhaul/repair as
pa necessary 30,000
Debt retirement, Bonds of 1990 70,000 II
General Repairs 15,000 II' 115,000
1992 General Repairs 15,000
15,000
1993 General Repairs 30,000 II
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30,000
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