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Photograph showing the Milltown Dam Power House.

Milltown Dam: Other Issues

Tax Issues

Some local residents have expressed concern that important property tax revenue would be lost if the dam is removed. Northwestern Energy paid taxes to the Bonner School in the amount of $85,811 in 2002. While this represented less than 4% of the school's budget, it is a significant issue in the local community.

The taxable value of the dam has been steadily declining over the past several years:

Table 1: Taxable Value of the Dam
Year Taxable Value
1999 $1,078,014
2000 $ 675,988
2001 $ 570,150
2002 $ 529,211

Similarly, tax payments to the school declined.

Total property taxes paid by Northwestern to Bonner School District:

Table 2: Total Property taxes Paid
Year Taxes Paid Property Taxes Paid
1999 $137,773
2000 $ 97,741
2001 $ 87,102
2002 $ 85,811

It would require a total of 161 homes at an average $100,000 market value to replace the property tax revenue generated by the Milltown Dam in 2001.

Missoula County believes that the cleanup will result in increased property tax revenue for the school. Cleanup contractors have paid business equipment tax on equipment used during the cleanup. The project will result in more than $100 million being spent in the local economy, which will inevitably result in increased property tax collection. The cleanup will restore clean water in the aquifer, where landowners are currently unable to develop water resources on their land. And it will result in a more attractive and desirable place to live, free of the stigma of a contaminated Superfund site. This will enable the community to pursue a more positive future.

Did the dam protect Missoula from floods?

No. Because the dam was a “run-of-the-river” dam, there was no storage capacity to protect downstream interests. Floods simply poured over the top of the dam. There was no flood storage in the Milltown reservoir. It was only an average of four to eight feet deep.

Did the dam prevent sediments from being washed down river?

No. The reservoir was simply a “rest stop” for contaminated sediments. During spring high flows, ice jams, and other natural, commonly recurring events, contaminated sediments were scoured from the reservoir and washed down river. The resulting pollution was much worse than if the dam had not been in place.

Should they have cleaned up the sediments but left the dam?

The cleanup alone may have cost about $75 million. Upgrading the dam for safety purposes would have cost another $30 to $50 million. No company could be expected to pay such a high cost for a dam that produced so little power (average 1.5 megawatts) and lost more than $200,000 per year. If the dam had been left in place, the companies would not have wanted the ongoing liability for continued cleanup and impacts to fisheries. If the dam had been left in place, groundwater would have continued to be polluted with arsenic, sediments would have been scoured out by ice jams, northern pike would have continued to breed, and fish still would have been unable to pass to spawning streams. The reservoir would have needed to be dredged out again in 10 to 20 years, costing another $100 million. For these reasons, EPA made it very clear that it would not consider an option that left the dam following sediment cleanup.

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