HomeMy WebLinkAboutWater Task Force/Reservoir/Water Plant Minutes 03.04.1996•
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I ? MO RMSON
I
MAERLE, INC.
An Emplo,vee-Owned Company
March 4, 1996
Jim Flisrand
C;'y of Laurel
115 West 1st
Laurel, Montana 59044
Re: Zone 2 Reservoir Location
MMI #0703.007-040-0211
Dear Jim:
ENGINEERS
SCIENTISTS
SURVEYORS
PLANNERS
2020 GRAND AVENUE • BILLINGS, MT 59102 • 406-656-6000 • FAX: 406-656-3432
On Febr?:ary 29, you requested that we take a look at the impact of moving the Zone 2, 1.0
million gallon water storage reservoir, as proposed in the City's 1994 Water Treatment and
Distribution i"vlaster Plan. The Zone 2 tank was proposed to be 20 feet high with a bottom
elevaticni of 3520. To move the water tank to a new location which is approximately 20-30
feet lower than the elevation as proposed by HKM in the Water Treatment and Distribution
?;.aster Plan (Site 1), the impact will be minimal.
By locating the water tank at an adjacent lower elevation (Site 2) the northern boundary of
Zone 2, as define] in the HKM Master Plan, will move to the south a distance approximately
equal to that of the elevation change from Site 1 to Site 2. In this case, the elevation change
is 30 feet therefore, the northern boundary of Zone 2 will move from the 3440 contour to 4
3410. The area between the 3410 contour and the 3440 contour can no longer be served by
the proposed tank if it is located at Site 2.
Some of the elevation head that is lost by lowering the elevation of the storage tank can be
offset by installing a tank that is 30 feet high in leu of the 20 foot high tank that HKM based
their original proposals on. If this is done ten additional feet of elevation head can be gained
to help make up for the 30 feet of elevation lost. Installing a 30 foot tank will make the net
elevation change from Site 1 to Site 2 roughly 20 feet. The elevation of the northern
boundary of Zone 2 would then be located at the 3420 contour. The approximate location of
the 3420 contour has been highlighted on the attached map.
Because the topography in the area of the Cove Ditch is relatively steep the additional service
area that would be provided by locating the tank at Site 1 is not significant (see attached
drawing for land area estimate). Tile lower valley area will be served just as well with the
tank at either location.
1 9 4 5 H a If A C e n t u r y 0 f S e r v i c e 1 9 9 5
MORRiSON
MAIERLE, INC.
Jim Flisrand
City of Laurel
March 4, 1996
Page 2
It was proposed by HKM that a booster station be used to serve Zone 3. Moving the water
tank to Site 2 may increase the horsepower requirement of the booster pumps. Based on the
small amount of land area involved and only 15-20 additional feet of elevation head it is
anticipated that this increase would be minimal.
Please let us know if any further investigation of this subject will be required.
Sincerely,
MORRISON MAIERLE, INC.
David N. Mosser
Project Manager
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MMI #0703.007-040-0211
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March 4, 1946