7 Fire Risk in Tumalo Watershed and Water Treatment
Primarily, however, the filtration treatment method was selected as the best available technology to allow the City continued use of the surface water in the event of a fire in the watershed that contains a significant portion of dead trees as a result of beetle kill. {A-11, B-5}
Comments: Mr. Hickmann’s comments here, and on prior occasions, regarding the City’s plans for managing watershed fire risks contain inherent contradictions and reveal deficiencies in SWIP cost estimates. Fire in the watershed is a major risk for the City’s surface water system. According to the US Forest Service this is an issue of when – not if – such a fire will occur. Given this, the value engineering team commissioned by the City recommended completion of a system which would in fact be prepared to operate in the event of a forest fire in the watershed (Final Value Engineering Study report, March, 2011). The Public Works department rejected this recommendation, arguing that the City could operate on ground water only for the minimum of 3 to 4 months required for equipment procurement, (installation time not estimated) if a fire occurred (VE report, Appendix J, Item T-53). This seems inconsistent with the City’s argument regarding unreliability of the well system (addressed in Section 4).
The proposed membrane treatment plant, under the current SWIP proposal, will not be equipped with the necessary add-ons required to treat water after a watershed fire, and no cost estimates for these add-ons are available. In the fall of 2011 Mr. Hickmann stated at a meeting that equipment for fire consequences would entail a capital investment of greater than $3 million, but offered no comment on operating and maintenance expense increases that would follow; these in all likelihood will be substantial. One can conclude that expense estimates for the City’s commitment to a membrane treatment plant lack credibility.
Furthermore the fire scenario planning comes back to the water supply issue discussed above. If the City proposes to be able to operate for many months on ground water only while the treatment plant is upgraded after fire in the watershed, the ground water system surely must meet reliability and firm supply standards. Yet Mr. Hickmann argues that currently our well infrastructure does not have adequate reliable capacity to operate without surface water supplementation. He can’t have it both ways.
On top of this, the City has now proposed that if the EPA grants an LT2 rule compliance delay, the City could install the new pipe without a treatment plant. Again this can only be a rational plan if in fact well water infrastructure is sufficiently reliable to meet capacity demand after a fire.
