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Fire report focuses on watersheds

Charles Levinson, Sierra Sun

The group of experts assembled to assess the damage caused by the Martis Fire sent off their recommendations to the U.S. Forest Service regional office in Ogden, Utah, and are awaiting approval.

According to members of the team, the task was complicated by the fire’s proximity to sensitive watersheds.

Both Bronco and Gray creek feed the Truckee River, which in turn provides Reno with 60 percent of its drinking water. Both Bronco and Gray Creek are steep watersheds that have historically been considered vulnerable to erosion and sedimentation.

They were also two of the most heavily impacted areas in the Martis Fire, which is only exacerbating the problem.

The Burned Area Emergency Rehabilitation Team devoted significant energies to those watersheds because of the fact that Reno is dependent on the water and because the Lahontan Cutthroat, an almost endangered species, calls the Truckee River home.

Of highest concern for the BAER team are the areas that experienced high intensity burning. Only 6 percent of the burned area around the Bronco Creek watershed and less than 1 percent of the burned area around Gray Creek burned at high intensity.

The Martis Fire was hailed in its early days as the fastest spreading blaze in years. Two thousand acres per hour was the oft-cited statistic. One fortunate consequence of a fire that actually spread like wildfire was that it did not burn in place for extended periods of time.

“The fire burned really fast and because of that it didn’t sit in on place and burn down deep into the soils,” said Genny Wilson, a Humboldt-Toiyabe wildlife biologist and BAER team member. “That’s one of the reasons we didn’t see a lot of high intensity burning. The fire just sort of blew over those areas.”

A high intensity burn means that the brush burned all the way down. The only remnants of former shrubs are burnt stubs in the ground. There are no needles on the trees, and all the ground cover has been burnt away. In a high intensity burn all the absorbent material in soil has been burnt away. Water will not be soaked into the ground. Erosion becomes a bigger issue.

Erosion can be slowed through the felling of dead trees horizontally across the slopes, straw wattles, reseeding efforts and loose rock dams in the creeks themselves.

However even before the Martis Fire, erosion had been an issue in the Bronco and Gray creek watersheds. According to Wilson, Forest Service documents going back to the 1960s show erosion issues here. This is in part due to natural causes – the terrain is steep and rocky with soiled areas interspersed throughout.

“A lot of [the erosion issues] is from natural terrain and a lot of it is from past activities and people in the area; it’s kind of both,” Wilson said.

As far back as the Comstock mining era these hillsides were logged. And as recently as the 1970s there was still cable logging in the area.

Fortunately, both Bronco and Gray creek appear thus far to be faring well in the fire’s aftermath. A creek’s health is often measured by the number of aquatic vertebrates living in the water. A lot of bugs means a healthy, well-oxygenated river. Wilson said that they found both creeks to have a high oxygen content and a lot of aquatic invertebrates.

This was before Monday’s thunderstorms, however, which reportedly caused mudslides and high sedimentation into the river. As long as such storms are relatively isolated events, Wilson said the fish and the river’s health should be okay.

While fish and drinking water may be adversely affected by post-inferno erosion issues, the BAER team’s number one concern, human life and property, is not threatened by landslides. Wilson said both Floriston and Interstate 80, the two heavily populated areas potentially threatened, have been deemed to be in no greater danger than they were before the fire.

One of the final concerns for the BAER team is noxious weeds, or non-native, invasive plants, replacing the burnt off flora.

“It’s a big deal,” said Wilson of noxious weeds.

With the forest’s protective duff reduced to ash, seeds from invasive plants can be dropped off from bulldozers, fire engines and other vehicles in the area to fight the fire.

These non-native plants do not act the same as native plants do. Their roots do not go as deep, thus they don’t absorb as much as water and act as a stabilizing force on the hillside. Local wildlife does not thrive on them the same as native plants. Wilson said as many as 4,600 acres per day are being converted to non-native species in the Western United States. She calls it the slow-moving wildfire, and warns that the impact will be long term.

To combat invasive, noxious weeds, teams will be monitoring the burned area for three years, and removing by hand any invasive plants found to be sprouting.

The final approval for funding of the BAER team’s recommendations is expected sometime next week and implementation will begin immediately.

The BAER team consisted of 10 people, including a botanist, hydrologist, a wildlife biologist, a fisheries biologists, a wilderness ranger, an engineer and an archaeologist.


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