Last evening the layers of mountain valleys to the west and north were filled with smoke from the High Park fire west of Ft Collins, Colorado. The valleys full of haze reminded me of the Smokey Mountains of Kentucky in the evening.

The fire is 25 miles as the crow flies from my house. The prevailing winds have been highly variable, but the recent front that passed through caused the smoke to blow towards my home town over the weekend. The air is usually clear enough to see Pikes Peak 100 miles to the south. But of late the visibility and air quality has been quite poor.

Colorado has seen waves of growth over the years, much of it along the I-25 corridor and the major east/west routes through the mountains. A common aspiration here is to have a home in the mountains. The housing boom of the last 20 years lead to the spread of MacMansions perched on mountain tops and slopes. Buyers with enough wealth or credit were able to pay the high expense of building a dream home in a remote location and pay for drilling a well in hard rock and running a long powerline up to the site.

What we are seeing is the negative side of having a home in the forest- crown fires that burst through the forest at speeds that surprise everyone. The thermal emissivity of a stand of flaming pine trees is quite high, first dessicating adjoining trees then heating the pine resins to the ignition point either by radiant energy, flame impingement, or by the spread of embers.

A major worry for the High Park fire in particular is the effect on rivers and municipal drinking water reservoirs by rain and snow runoff from the burned ground.  A smokey flavor is desirable for a barbeque sauce but not for tapwater.

This fire seems to be headed for the number one forest fire in Colorado history. Time will tell.