May 10, 1999
WOODINVILLE--The City Council has approved installation of a radio telemetry interconnection system for NE 175th, as proposed by United Signal Control, Inc. The system will coordinate timing of the five signal lights on NE 175th between 131st NE and 140th NE, improving vehicle travel.
United Signal offered the city a 90-day guarantee, instead of their usual one of 15 days, said City Director of Public Works Mick Monken.
"I will make sure that 90 days does not start until the whole system is up and running," said Monken. The agreement also gives the City 45 days to test the equipment before paying for it.
The new system will replace a plan for a hardwire system, approved by the Council in February. That system would have required a four-week traffic disruption by trenching the length of 175th. The telemetry system will avoid trenching and allow easier and cheaper installation and expansion of the interconnection system.
"Although the hardwire system is a proven technology, compared to the telemetry system, it has a significantly higher cost and offers no flexibility for future expansion without installing more conduits," said Monken. "The radio telemetry system offers the potential of the same deliverable service, easy expansion, and lower cost for implementation."
Radio telemetry systems have been used successfully by the military since the 1940s. The units are also Y2K-proof.
"The cost of the controller units are the same as those for the hardwire units, but the telemetry units have built-in traffic counters with a history-gram for future reference. Those counters, which cost $5,000 if bought separately, can be a great demographic feature," said Monken.
The estimated cost for the telemetry system is $16,000 for the hardware and $12,500 for installation and monitoring. The hardwire system would have cost the City $70,000 for King County's installation charge, $12,500 for installation, and almost $40,000 for engineering design and specifications.
"We do risk a loss of $12,500 if the telemetry does not satisfy our needs, but success means a savings of about $80,000," said Monken.
King County traffic signal operations staff performed a bench test on the telemetry system and supported the technology. The County will now perform additional bench tests on the units the City will receive before installation.