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The jury-rigged system we have working now has a sensor on the water line in the booster <br />station. We have determined that we are about 5 feet off from sensing the correct water tower <br />level in the morning and up to two feet off in the afternoon. Based on this and a search for a <br />different sensor we have determined that there are no sensor controls that can be installed in the <br />water lines at the booster station that can sense the water levels in the tower accurately enough to <br />meet our needs. <br />We tested and determined that a 900 Mhz radio system between the water tower and the booster <br />station can provide the needed reliable communications needed. A 900 Mhz radio system does <br />not require a license and also, does not require a clear line of site (no trees in the way) between <br />the antennas to function properly. <br />Based on the above, staff requested proposals from two contractors who know our control <br />system. The proposals are for both a (one -way) unidirectional system that will enable the water <br />tower to send signals to the booster station and a (two -way) bi- directional system that will enable <br />city crews to view tank level, alarms, and set -point controls at either location. The advantage of <br />the bi- directional system is that City crews can respond to problems at either site, instead of have <br />to go to the booster station first and if needed go to the water tower as required with the <br />unidirectional system. Both proposals also include needed uninterruptible power supplies and <br />the installation an antenna tower. They are: <br />Company Unidirectional Bi- directional <br />Duane Nielsen Co. $7,600.00 $10,700.00 <br />Connelly Industrial Electronics $8,099.19 $9,656.06 <br />Staff would have to purchase and install a tower at the booster station to support an antenna at an <br />estimated additional cost of$1250. <br />During the Planning Commission meeting, staff was asked if it was possible to have a tower <br />installed by one of the cellular companies and we mount our antenna on it. Staff contacted <br />American Tower Company who installs and leases antenna tower space to cellular companies. <br />They indicated that the cellular companies already have the area by the booster station fully <br />covered and there would be no need for another antenna in this area. He further indicated that <br />there is sufficient existing tower space in the area to meet any needs for increased capacity. In <br />addition, based on the low elevation of this site, if a future need was identified, the tower would <br />have to be at least 150 to 175 feet tall. The cost to install a tower to this height would result in a <br />high cost antenna space, which would negatively impact payback. Based on this staff is not <br />recommending constructing a commercial tower at this location. <br />This project is listed in the 2004 Water and Sewer Capital Budget for $8,000. However, we were <br />not going to pursue this project until we determined if the City of Little Canada was to keep the <br />water system or the communication system failed. <br />Based on the total annual cost of $1,944 per year for our existing unreliable system we could pay <br />off of the unidirectional radio system in about 4.5 years and a bi- directional radio system in just <br />HL \GregS \Water \Booster Station Antenna Tower 1.doc <br />