High and muddy waters, filled with sediment, ash and debris, flow through the Poudre River below the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Megan Sears, a field technician with the United States Forest Service, collects a water sample from a tributary to the Poudre River inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

The Cameron Peak fire burn scar is pictured above the Poudre River west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

The Cameron Peak fire burn scar is pictured above the Poudre River west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Katie Willi, left, and Megan Sears, right, both with the United States Forest Service, collect a water sample from a tributary to the Poudre River inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021.

A burnt log sits inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Burnt paneling and windows are seen on the side of an outhouse at a campground along the Poudre River inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

The Cameron Peak fire burn scar reaches the shoreline of Chambers Lake, at the headwaters of the Cache la Poudre River, west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Burnt trees stand inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Debris, sediment and ash floats down a tributary of the Poudre River inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

The Cameron Peak fire burn scar is pictured above the Poudre River west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Megan Sears, in river, and Katie Willi, behind shrubs, both with the United States Forest Service, collect data and water samples along a tributary to the Poudre River inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Workers with the Larimer County Conservation Corps load sod logs, used for erosion control, into the back of a work truck near the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Two boats makes their way across Horsetooth Reservoir, the main supply of drinking water for the city of Fort Collins, west of Fort Collins, Colorado, U.S., June 4, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

A boat makes its way across Horsetooth Reservoir, the main supply of drinking water for the city of Fort Collins, west of Fort Collins, Colorado, U.S., June 4, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

A surfer floats down the Poudre River while riding at the Poudre River Whitewater Park in Fort Collins, Colorado, U.S., June 4, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

The high water mark and the remains of burnt trees and pine needles are pictured along a tributary to the Poudre River inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

New vegetation, barren soil and burnt trees are pictured inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Ian Lilya, a field technician with the United States Forest Service, prepares to collect a water sample along a tributary to the Poudre River inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

The Cameron Peak fire burn scar meets the Poudre River west of Fort Collins, Colorado, U.S., June 3, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Megan Sears, Katie Willi, and Ian Lilya, all with the United States Forest Service, walk past a section of the Cameron Peak fire burn scar near the Poudre River west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

A bicyclist is reflected in a broken glass mural, shaped like the nearby Poudre River, while riding through Fort Collins, Colorado, U.S., June 4, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

A burnt tree lays across a tributary to the Poudre River inside the Cameron Peak fire burn scar while Katie Willi, Megan Sears and Ian Lilya, all with the United States Forest Service, collect water quality data west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.

Katie Willi, Megan Sears and Ian Lilya, all with the United States Forest Service, collect water quality data along a tributary to the Poudre River inside the Cameron Peak fire burn scar west of Fort Collins, Colorado, U.S., June 29, 2021. Huge forest fires last year denuded vast areas of Colorado’s mountains and left them covered in ash – ash that with sediment has since been washed by rains into the Cache la Poudre River.