restoring humboldt county's mattole canyon creek
Dave Brooksher -- reporter for The Redwood Times, Garberville, Calif.
It might be fair to argue that the secret ingredient in the Mattole Canyon Creek's restoration has been Gil Greggori and his family, who live a few miles downstream from the grow-site reportedly being investigated by the Humboldt County District Attorney's Office. Gregori's in property management, and owns businesses in the Bay Area. More than 30 years ago, Gil bought acreage in the Mattole Canyon Creek watershed, and since then the Greggori family has built a homestead near the mouth of the creek where it runs into the main stem of the Mattole.
Since then they've invested significant time, effort and money to rehabilitate the delta. It has been a massive project -- with Gil Greggori taking a few thousand willow cuttings by hand every year for the last three decades.
Ten years ago the Greggoris was awarded just over $3,000 from the California Department of Fish and Game's Fisheries Restoration Grant Program for the revegetation of Mattole Canyon Creek's delta. Since that, Gil says they've gotten other, larger grants.
"There's been a lot of work done. A lot of trees planted. Fifty or sixty thousand willows," Gil Greggori says. "We backed those up with black cottonwood, and backed those up with redwood."
Some of those redwoods are even starting to look established.
They also tried importing heavy rocks to line the stream bed, but due to the costs involved they felt that re vegetating the stream-bank gave them more bang for their buck.
The before and after pictures speak for themselves. Thirty years ago, the Mattole Canyon Creek's delta was a moonscape of sediment and rock. Today, the flood plain is a well vegetated riparian zone with trees, shrubberies, and lush grass. Neighbors have taken to using it as a community park, with a well manicured baseball diamond and a frisbee golf course.
The trick has been to create a primary stream channel.
Due to high volumes of sediment, the creek would fill itself in on a regular basis -- forcing water flowing through the creek to cut another path on it's way to the Mattole. As a result, this meandering creek bed would move from year to year, wandering over an area roughly 500 feet wide.
Over time, however, vegetation has stabilized the stream-banks. Water flow has been successfully directed into primary and secondary channels. Streambed scour has improved dramatically, digging down roughly 8 feet in one location and establishing a permanent path of travel through the flood plain. That path is also more narrow, helping the water to maximize the effects of it's kinetic energy and move excess sediment more efficiently downstream toward the Pacific.
"It's going to have to go all the way to the ocean in order to have a healthy system again," Greggori says.
It was largely an issue of finding a way to help the water dig down far enough to hit the boulders and larger sediment that reinforced the bottom of the creek's historical path through the flood plain, before the excess sediment produced by by the post-war logging boom of the 1950s and `60s.
With the dramatic reduction of canopy covering the ground, rainfall's impact on the terrain below increased. Rain hit the ground directly, dislodging soil and moving it downslope into the creek. Logging roads further exacerbated the problem.
"So the sediment up on top in the headwaters comes downhill and settles. When it settles it builds up in the creeks and the river and makes the gravel the wrong kind for all the creatures. The salmon can't make their reds, or their nests. It kills the fish, it kills everything," Gregori says. "All that gravel and dirt and vermiculite has to be taken out manually, which is impossible, or it has to go to the ocean."
It's hard to quantify the number of individual restoration projects that have taken place in Mattole Canyon Creek -- and it depends how you count them. Listing each culvert separately would result in a higher number than just counting the funding sources and successful grant proposals. Gregori estimates that more than 20 restoration projects have been executed in Mattole Canyon Creek over the years. More conservative estimates place that number at more than a dozen.
Restoring a decimated watershed takes a lot of work, money and time. It takes the support of state and federal agencies, local non-profits, and individual volunteers.
All of those things are necessities. But in this case, there was another factor at play. Someone with the material resources and sheer force of will required to reverse decades of environmental damage and neglect purchased the land and fixed it himself.
More than anything else, this work seems to take patience. Greggori says that after thirty years of environmental degradation and thirty years of restoration efforts, Mattole Canyon Creek is just getting back on it's feet. But it's not done yet.
One can still see a high level of fine sediment filling in the space between larger chunks of gravel in the streambed, despite recent Steelhead sightings that suggest the fish are coming back.
It remains to be seen how the increasing number of large-scale marijuana grows observed in recent years will affect the ongoing recovery of fish populations. Gil Greggori likens their impacts to those seen in the coal mining industry. Due to the use of heavy logging and excavation to clear space for larger grow-sites, he calls the mega-grows a kind of mountaintop removal.
Greggori was critical of recent news coverage, but helpful in researching this article.
"There isn't much to say about it because you don't know what's going to happen yet," he says. "It's a great start, but where is it going to end up?"
"It's a big picture in the paper -- that's great," Greggori says. "But is Fish and Wildlife going to do something? They weren't able to do anything about the logging or anything else that's happened, so why would they be able to do anything about this?"
Since then they've invested significant time, effort and money to rehabilitate the delta. It has been a massive project -- with Gil Greggori taking a few thousand willow cuttings by hand every year for the last three decades.
Ten years ago the Greggoris was awarded just over $3,000 from the California Department of Fish and Game's Fisheries Restoration Grant Program for the revegetation of Mattole Canyon Creek's delta. Since that, Gil says they've gotten other, larger grants.
"There's been a lot of work done. A lot of trees planted. Fifty or sixty thousand willows," Gil Greggori says. "We backed those up with black cottonwood, and backed those up with redwood."
Some of those redwoods are even starting to look established.
They also tried importing heavy rocks to line the stream bed, but due to the costs involved they felt that re vegetating the stream-bank gave them more bang for their buck.
The before and after pictures speak for themselves. Thirty years ago, the Mattole Canyon Creek's delta was a moonscape of sediment and rock. Today, the flood plain is a well vegetated riparian zone with trees, shrubberies, and lush grass. Neighbors have taken to using it as a community park, with a well manicured baseball diamond and a frisbee golf course.
The trick has been to create a primary stream channel.
Due to high volumes of sediment, the creek would fill itself in on a regular basis -- forcing water flowing through the creek to cut another path on it's way to the Mattole. As a result, this meandering creek bed would move from year to year, wandering over an area roughly 500 feet wide.
Over time, however, vegetation has stabilized the stream-banks. Water flow has been successfully directed into primary and secondary channels. Streambed scour has improved dramatically, digging down roughly 8 feet in one location and establishing a permanent path of travel through the flood plain. That path is also more narrow, helping the water to maximize the effects of it's kinetic energy and move excess sediment more efficiently downstream toward the Pacific.
"It's going to have to go all the way to the ocean in order to have a healthy system again," Greggori says.
It was largely an issue of finding a way to help the water dig down far enough to hit the boulders and larger sediment that reinforced the bottom of the creek's historical path through the flood plain, before the excess sediment produced by by the post-war logging boom of the 1950s and `60s.
With the dramatic reduction of canopy covering the ground, rainfall's impact on the terrain below increased. Rain hit the ground directly, dislodging soil and moving it downslope into the creek. Logging roads further exacerbated the problem.
"So the sediment up on top in the headwaters comes downhill and settles. When it settles it builds up in the creeks and the river and makes the gravel the wrong kind for all the creatures. The salmon can't make their reds, or their nests. It kills the fish, it kills everything," Gregori says. "All that gravel and dirt and vermiculite has to be taken out manually, which is impossible, or it has to go to the ocean."
It's hard to quantify the number of individual restoration projects that have taken place in Mattole Canyon Creek -- and it depends how you count them. Listing each culvert separately would result in a higher number than just counting the funding sources and successful grant proposals. Gregori estimates that more than 20 restoration projects have been executed in Mattole Canyon Creek over the years. More conservative estimates place that number at more than a dozen.
Restoring a decimated watershed takes a lot of work, money and time. It takes the support of state and federal agencies, local non-profits, and individual volunteers.
All of those things are necessities. But in this case, there was another factor at play. Someone with the material resources and sheer force of will required to reverse decades of environmental damage and neglect purchased the land and fixed it himself.
More than anything else, this work seems to take patience. Greggori says that after thirty years of environmental degradation and thirty years of restoration efforts, Mattole Canyon Creek is just getting back on it's feet. But it's not done yet.
One can still see a high level of fine sediment filling in the space between larger chunks of gravel in the streambed, despite recent Steelhead sightings that suggest the fish are coming back.
It remains to be seen how the increasing number of large-scale marijuana grows observed in recent years will affect the ongoing recovery of fish populations. Gil Greggori likens their impacts to those seen in the coal mining industry. Due to the use of heavy logging and excavation to clear space for larger grow-sites, he calls the mega-grows a kind of mountaintop removal.
Greggori was critical of recent news coverage, but helpful in researching this article.
"There isn't much to say about it because you don't know what's going to happen yet," he says. "It's a great start, but where is it going to end up?"
"It's a big picture in the paper -- that's great," Greggori says. "But is Fish and Wildlife going to do something? They weren't able to do anything about the logging or anything else that's happened, so why would they be able to do anything about this?"
Gil Greggori
After decades of restoration work, Mattole Canyon Creek is showing signs of improvement. In the early 1990s, the Mattole Restoration Council undertook a massive project excavating the creek bed, deepening it's channel, reconfiguring bends in the stream, installing tree-trunks along the banks, and planting willows to stabilize the soil along a mile and a half of the waterway. Revegetation projects have established a healthy riparian zone where the reintroduction of plant and root systems have stabilized sediment along the channel, improving stream-bed scour and the efficiency with which the water moves fine sediment out toward the ocean. Crumbling bridges built with chemically treated lumber were replaced by concrete structures rated to withstand a 100 year flood.
Mattole Canyon Creek had a very good year in 1996. Records show that coho-salmon, king salmon and steelhead were all observed that year. Surveys in 1994 and 1995 showed no salmonid presence, as did another survey in 1997. Steelhead were observed again in 1999, 2001 and 2002 but the coho and king salmon had not come back.
Another series of four surveys in 2008 and 2009 indicate that coho and king salmon were still absent from Mattole Canyon Creek. Steelhead were observed, but they were not the focus of the surveys.
"There's no funding for a steelhead recovery plan in the Mattole because their recovery status is more secure than the coho," said Amy Hoss, with the Mattole Salmon Group.
The Mattole Salmon Group's records for Mattole Canyon Creek go back to 1994 -- nearly 20 years -- and it's been almost that long since salmon were last sighted.
Excess sedimentation is still a concern. For many years, the constant introduction of sediment into the creek made it shallow and wide, warming the water as slowed down over an increased surface area. as is water temperature. The Mattole Salmon Group's monitoring indicates that Mattole Canyon Creek's temperatures are currently above the threshold for coho. As a result, Amy Baier says there are no plans to survey it this year. It doesn't meet the criteria necessary to justify allocating funding for dive-surveys -- so we can't expect new data on the creek's recovery any time soon. It will remain difficult to assess progress in the creek's recovery -- as it always has been.
"Measuring the impact of the restoration projects upon the water quality and salmon is sketchy at best because the accumulated impacts of human activities and weather will take years to repair and heal. 'It has taken 30 or 40 years to put the watershed in this condition, and it's going to take more than a few years to fix it, if we can,'" Jim Hopelain, then an employee of the Department of Fish and Game, told Biodiversity News in Vol. 1 no. 5 of their newsletter in 1994.
Mattole Canyon Creek had a very good year in 1996. Records show that coho-salmon, king salmon and steelhead were all observed that year. Surveys in 1994 and 1995 showed no salmonid presence, as did another survey in 1997. Steelhead were observed again in 1999, 2001 and 2002 but the coho and king salmon had not come back.
Another series of four surveys in 2008 and 2009 indicate that coho and king salmon were still absent from Mattole Canyon Creek. Steelhead were observed, but they were not the focus of the surveys.
"There's no funding for a steelhead recovery plan in the Mattole because their recovery status is more secure than the coho," said Amy Hoss, with the Mattole Salmon Group.
The Mattole Salmon Group's records for Mattole Canyon Creek go back to 1994 -- nearly 20 years -- and it's been almost that long since salmon were last sighted.
Excess sedimentation is still a concern. For many years, the constant introduction of sediment into the creek made it shallow and wide, warming the water as slowed down over an increased surface area. as is water temperature. The Mattole Salmon Group's monitoring indicates that Mattole Canyon Creek's temperatures are currently above the threshold for coho. As a result, Amy Baier says there are no plans to survey it this year. It doesn't meet the criteria necessary to justify allocating funding for dive-surveys -- so we can't expect new data on the creek's recovery any time soon. It will remain difficult to assess progress in the creek's recovery -- as it always has been.
"Measuring the impact of the restoration projects upon the water quality and salmon is sketchy at best because the accumulated impacts of human activities and weather will take years to repair and heal. 'It has taken 30 or 40 years to put the watershed in this condition, and it's going to take more than a few years to fix it, if we can,'" Jim Hopelain, then an employee of the Department of Fish and Game, told Biodiversity News in Vol. 1 no. 5 of their newsletter in 1994.
“Geologic material in this area is relatively soft and highly fractured sandstone and loosely structured shale decomposing to clay. Sandstone slopes over 50% are prone to sliding and slumping. Slopes of clay and decomposing shale over 25% are prone to rotational slumping when saturated with water. Gradients adjacent to streams in this section range up to 90% and are extremely unstable... As a result, some of the creeks in this region, such as Mattole Canyon Creek, have experienced massive erosion... Each winter, the water would carve out a new channel, fill it up with sediment, and move again, never re-establishing a permanent channel with riparian vegetation. The creek would form numerous small channels near its mouth, braiding their ways down to the Mattole River."
Mattole Canyon Creek has history. It was badly impacted during the timber boom after World War II. Clearcuts and logging roads led to frequent sediment blowouts in the creek. Impacts from logging roads were exacerbated by numerous water-crossings, and bridges made with chemically treated lumber that introduced creosote and other contaminants into the watershed.
More recently, it's been subject to similar impacts on a smaller scale due to illegal water-diversions, unpermitted roads and excavation associated with clearing space for large marijuana grows. In some cases, growers have cut down trees to allow more sunlight into their gardens. One such operation was highlighted on the front page of the Redwood Times, on Tuesday, March 26th.
It's difficult to clearly differentiate the human impacts on Mattole Canyon from the ones created by the watershed's natural topography. Steep slopes and unstable grounds are subject to landslides. Significant and constant erosion frequently impacts the streambed's path of travel to the main stem of the Mattole.
The Mattole Restoration Council explained how this process is at work in Mattole Canyon Creek in a 2006 "Sediment Assessment Report: Blueslide to Grindstone" :
More recently, it's been subject to similar impacts on a smaller scale due to illegal water-diversions, unpermitted roads and excavation associated with clearing space for large marijuana grows. In some cases, growers have cut down trees to allow more sunlight into their gardens. One such operation was highlighted on the front page of the Redwood Times, on Tuesday, March 26th.
It's difficult to clearly differentiate the human impacts on Mattole Canyon from the ones created by the watershed's natural topography. Steep slopes and unstable grounds are subject to landslides. Significant and constant erosion frequently impacts the streambed's path of travel to the main stem of the Mattole.
The Mattole Restoration Council explained how this process is at work in Mattole Canyon Creek in a 2006 "Sediment Assessment Report: Blueslide to Grindstone" :
