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<br />demolition of the eXlstmg structures, bypass flows, mmlmum instream flows,
<br />transmigration of fish, temporary intake to the raw water transmission line during
<br />construction, sluicing of captured sediments, passing of flood waters and wintertime icing
<br />conditions. Recreational uses may also have to be considered,
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<br />Alternatives
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<br />In the process of reviewing the conditions, alternative actions were considered, Three alternative
<br />actions are available, They are: no action (delay), alternative supply point with new pipeline and
<br />reconstruction at the existing site,
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<br />1, No action, do nothing until complete failure, The advantages of delay is initial cost savings,
<br />avoidance of site disturbance and no interruption of current operations, Disadvantages of delay
<br />are: lack of reliability of continued service, increasing risk of water treatment violations, inability
<br />of the Town to control critical operations if unexpected failure occurs and probable higher future
<br />costs due to failure. In the face of increasing risk of violation of drinking water standards due to
<br />high turbidity or outright loss of water supply due to failure of the diversion system, delay of
<br />action to improve the diversion of raw water does not seem prudent. Failure will eventually
<br />occur, If attended to now, site disturbance and temporary interruption of raw water intake can
<br />be planned and controlled.
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<br />2, Delivery of raw water by new pipeline, At least two possible rout~ for a pipeline have been
<br />discussed, One is an established pipeline from a point of connection to Longmont's Button Rock
<br />Reservoir supply line, routed down through the North St. Vrain Creek canyon and emerging
<br />upstream of the present Lyons' diversion site, The pipeline, now in disrepair and reportedly
<br />unusable, was placed on this route in about 1972, Another possibility is a new, longer pipeline
<br />route from Longmont's supply line directly to the treatment plant. Either of these has several
<br />advantages: efficiency due to minimal river losses, increased water quality to the WTP through
<br />most of the year, and probable increased reliability in extreme weather conditions,
<br />Disadvantages, however, are numerous, First, cost of either of these pipelines exceeds $2,0
<br />million, For the canyon route, complete replacement would be required since it is reportedly 6
<br />inches diameter (too small) and in poor condition, Visual impacts and construction impacts of the
<br />canyon route may trigger an environmental assessment. The other route crosses federal land
<br />uphill from the WTP, This, also, will require impact assessment to acquire right of way permits
<br />on federal property, Another potential disadvantage is that a pipeline will reduce water in the
<br />creek, impacting fisheries, wildlife, water-based recreation activities, Expensive legal
<br />proceedings are also required to change the point of diversion of Lyons' water rights, if and when
<br />a joint pipeline operating agreement can be obtained with the City of Longmont.
<br />
<br />3, Reconstruct the facilities at the existing site, Advantages to this alternative are several:
<br />reliability of water supply operations is increased considerably, the long-term cost is probably
<br />lower than either of the other options, water quality to the WTP will be improved, instream flows
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