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[Water_news] 3. DWR'S CALIFORNIA WATER NEWS: WATERSHEDS - 11/27/07

Department of Water Resources

California Water News

A daily compilation of significant news articles and comment

 

November 27, 2007

 

3. Watersheds

 

PROSPECT ISLAND:

California levee repair blamed for killing thousands of game fish - Associated Press

 

Putrid end for levee repairs; State crews clean up massive fish kill after Delta project - Sacramento Bee

 

Investigation into thousands of dead fish in delta - ABC Channel 7 (Bay Area)

 

Reclamation Bureau Won't Drain Prospect Island - News 10 (Sacramento)

 

Levee repairs leave fish high and dry - Fairfield Daily Republic

 

Delta island could be for sale - Fairfield Daily Republic

 

DELTA LEVEE ISSUES:

Rising sea could threaten region; Levee improvements needed by end of the century, experts say - Stockton Record

 

Editorial: A New Water Plan?; Taking the next step on the Delta - Vallejo Times Herald

 

INVASIVE SPECIES:

Snails pose threat via Lake Natoma trout hatchery; Tiny invasive species can travel inside fish, infest more waterways and destroy food source - Sacramento Bee

 

 

PROSPECT ISLAND:

California levee repair blamed for killing thousands of game fish

Associated Press – 11/26/07

By Juliet Williams, staff writer

 

SACRAMENTO—State and federal officials on Monday said they were investigating the death of thousands of game fish in the Sacramento-San Joaquin Delta after a federal agency drained the water around a protected island during a levee repair.

 

Masses of fish could be seen floating in shallow water on Prospect Island, a 1,253-acre plot next to Sacramento's Deep Water Ship Channel that is administered by the U.S. Bureau of Reclamation.

 

The bureau on Monday halted drainage of the remaining water behind the levee and started removing the fish carcasses, spokesman Jeff McCracken said. He said the agency would begin adding oxygen to the water in hopes of saving some of the remaining fish.

 

"When we realized how many fish were there, we quit pumping," he said. "By then, we certainly, apparently, had passed the point of causing some fish loss."

 

The bureau had no estimate on the number of fish killed. Bob McDarif, owner of Cliff's Marina near the delta town of Freeport, estimated the number in the tens of thousands.

 

"It's like a disaster out there," he said.

 

The California Department of Fish and Game launched its own investigation Monday, focusing on how and why the fish died.

 

Although the fish deaths were on federal land, the striped bass, salmon, carp, bluegill and other game fish are considered public trust assets for the state. The results will be sent to state Attorney General Jerry Brown.

 

The levee under repair is around Prospect Island, which sits along the shipping channel about 20 miles southwest of Sacramento. The channel is the same stretch of water that served as a conduit for a pair of humpback whales that made an unlikely journey inland from San Francisco Bay last spring.

 

In a project that began in early October, the Bureau of Reclamation plugged two breaks in the 15-foot-high levee and repaired about 600 additional feet. The breaches occurred in January 2006.

 

Pumping the remaining water from behind the levee was the final step.

 

McCracken said the bureau received clearance from the U.S. Fish and Wildlife Service to proceed with the repairs. Fisheries officials determined heavy vegetation would make it too hard to salvage the fish, but the contractor was advised to start pumping during the lowest tide of the month, which he did, McCracken said.

 

"To put nets or do things, they told us it wasn't plausible," he said. "We did instruct the contractor ... to move as many fish out of the way as possible."

 

The Fish and Wildlife Service studied the potential effects of the drainage project on the delta smelt, which is protected under the California Endangered Species Act. That study showed the levee repair was likely to have no effect on the fish.

 

State Fish and Game officials said they were notified about the die-off last Wednesday and were not involved in the levee project.

 

"We wish they would've consulted with us beforehand," department spokesman Steve Martarano said. "We could have maybe given them some ideas on things to do."

 

That could have included using sport fishing groups to help reduce the fish population before the water was drained or immediately rescue some fish. It also could have meant employing special water pumps that are less harmful to fish, he said.

 

McDarif, the marina operator, was first to sound the alarm about the stranded fish and said he has been frustrated by the slow response.

 

He recruited more than 100 volunteers to try to move the dying fish to the river, but he said his efforts were thwarted by federal officials.

 

"If I saw some fish dying now, I would go and take them out and move them to the river," he said. "The thing is, there's all these politics, and there's no time for politics."

 

The Bureau of Reclamation bought the island about 12 years ago as part of a planned Army Corps of Engineers program to restore fisheries and wildlife in the delta. Funding stalled, however, and the area was never developed.

 

The bureau had planned to sell the property this winter. #
http://www.mercurynews.com/news/ci_7563531?nclick_check=1

 

 

Putrid end for levee repairs; State crews clean up massive fish kill after Delta project

Sacramento Bee – 11/27/07

By Matt Weiser, staff writer

 

PROSPECT ISLAND – Thousands of dead fish lay rotting in the fetid brown water of this island near Rio Vista, white bellies turned up to clouds of seagulls gathered for an easy meal.

 

The fish are victims of a levee repair project gone sour, and on Monday, officials worked to contain the casualties.

 

A team of four government men in chest waders used hand nets to gather the dead fish – mostly striped bass, carp and catfish, some up to 2 feet long.

 

The crews went to work Monday as part of a belated response by the owner of this 1,200-acre Delta island, the U.S. Bureau of Reclamation. The agency responded after fishermen discovered the deaths last week and touched off a public outcry.

 

The men weren't talking, and it was hard to blame them: The task of dumping fish in smelly piles was unpleasant, and it seemed futile. They were working just one edge of an estimated 260 acres of standing water, all of it freckled with dead fish.

 

At this rate, it could take weeks to collect all the dead fish.

 

Over the weekend, the bureau developed a plan, endorsed by the state Department of Fish and Game, to help the surviving fish.

 

First, dead fish will be removed from the water to keep their decaying carcasses from depleting oxygen. Today generators arrive to run aerators to boost oxygen in the water.

 

"Fish and Game has told us that's the appropriate thing to do," said Jeff McCracken, a spokesman for the bureau. "They believe this will allow the fish that remain to survive just fine. They're saying there is no need to take those fish off the island and put them in the river."

 

In effect, surviving fish will live out their days in the shallow lake that remains on the island, McCracken said.

 

Critics aren't pleased.

 

"I guarantee, when they get done, they won't save one fish," said Bob McDaris, owner of Cliff's Marina in Freeport, who led a citizen effort to save the fish. "How are they going to live out there in that water? You gotta be dumber than a post to leave those fish out there in that 8 inches of water."

 

McDaris had 32 volunteers at the marina on Monday, ready to rescue the fish. He had available donated helicopters, amphibious vehicles, airboats and pumps.

 

Government officials said they don't need volunteers.

 

"But we certainly are going to re-evaluate this as we go through this process, because we know it's important to them," McCracken said. "If there's some way they can help, we certainly would welcome that."

 

The incident began to unfold last month when the bureau hired a contractor to close two levee breaks that occurred during storms in January 2006.

 

The bureau felt obligated to repair the breaks because of liability concerns. Water washing out of the breaks with tidal action was eroding a neighbor's levee, and causing boats to capsize.

 

But amid the levee-repair work, no plans were made for fish that had found a home on the flooded island.

 

When construction crews began pumping water off the island two weeks ago, fish began to die by the score in declining water.

Many also were ground up by the pumps.

 

Rocklin resident Dave Martin was fishing on Miner Slough adjacent to the island on Saturday, Nov. 17, when he saw thousands of dead fish near the outlets discharging water from the island.

 

"There were a lot of fish in there, still alive with their tails cut off, but they couldn't go anywhere. They couldn't swim," he said.

 

"It was really sad. I got home and kept thinking about it and I thought, 'This just isn't right.' "

 

He called Fish and Game's crime tip hotline the next day to report what he saw.

 

Fish and Game last week launched a criminal investigation into the stranding of the Prospect Island fish. On Monday, spokesman Steve Martarano declined to reveal likely targets of the investigation or what charges they might face.

 

The Reclamation Bureau consulted both the U.S. Fish and Wildlife Service and National Marine Fisheries Service before starting the levee repairs, to see if the fish required special accommodation. Both agencies said no, believing no endangered fish were affected.

 

Both McCracken and Martarano said the state Department of Fish and Game was not consulted specifically about the fish before levee repairs began. The agency enforces the state Endangered Species Act and state Fish and Game Code, which prohibits the "wanton waste" of sport fish.

 

Fish and Game did, however, consult with the Reclamation Bureau about whether a streambed alteration permit was required, both men said. Again, the answer was no.

 

For most property owners, Martarano said, such a permit includes provisions for managing fish affected by the project, and restoration work afterward.

 

But Martarano said rules are different when dealing with the federal government.

 

"There's a lot of legal complexities there," he said. "We have an ongoing investigation, so we're really not able to comment any further than that."

 

Since at least 1994, Prospect Island has been targeted for restoration to help Delta fish, which have been declining for years.

 

The plan was to intentionally breach the levees to create shallow fish habitat. But Congress never appropriated money for restoration, and the island has lain fallow ever since. #

http://www.sacbee.com/101/story/522934.html

 

 

Investigation into thousands of dead fish in delta

ABC Channel 7 (Bay Area) – 11/26/07

By Noel Cisneros

 

- The State Department of Fish and Game has ordered an investigation into a federal levee project that killed thousands of fish.

 

The federal government acquired Prospect Island in 1994 to turn it into an official wild life refuge, but their plan never materialized. Instead, the 1,200 acre marsh became a sanctuary to birds and wildlife on its own.

 

Earlier this month, feds moved to repair a broken levee and "dewater the island".

 

The aftermath of their project was tens of thousands of fish, suffocated in 18-inch deep water. The idea was to leave some water and accept a certain level of dead fish as collateral damage.

 

The Bureau of Reclamation say they got approvals from The State Water Resources Board and The Regional Water Board. They also said that they consulted with The Department of Fish and Game. Ten days into their project, they realized they had a problem.

 

"There was a failure here by a number of different groups to assess what the results of this could have been," says Jeff McCrackin, Bureau Of Reclamation.

 

That failure is now being scrutinized by the California Department of Fish and Game.

 

Carsten Gorritzen is a fisherman. He used to pull dozens of fish out of the water in an hour. Today he caught one -- and threw it back.

 

"When I first came to California four years ago, there were fish everywhere. Now, I hardly find any."

 

The Department of Fish and Game was on Prospect Island to scoop out the dead fish and make way for the survivors.

 

"I'm just here to help clean out the dead fish carcasses and give the live ones a better chance of survival," says Jason Dubois, Department of Fish and Game.

 

The idea with the current repairs is to restore the island to a natural state. They want it to have less water and eventually sell it.

 

It could become a hunting club, a refuge, or even a farm at some point in the future. #

http://abclocal.go.com/kgo/story?section=news/local&id=5785985

 

 

Reclamation Bureau Won't Drain Prospect Island

News 10 (Sacramento) – 11/26/07

By C. Johnson, Internet News Producer

 

The federal agency responsible for managing flood water on Prospect Island in the Delta has revised its plan after pumping the water out killed thousands of fish.

A levee break flooded the island in January 2006, and in the last 22 months, the island had become a fishing paradise. The breach was repaired and the U.S. Bureau of Reclamation had begun operating pumps to drain the island. However, thousands of fish from minnows to large striped bass were left stranded. The bureau stopped the pumps last Wednesday.

Since then, there's been a scramble to remove all of the dead fish and determine how to best proceed. Bureau spokesman Jeff McCracken told News10 on Monday that after consulting with the California Department of Fish and Game, a decision has been made to hire a contractor to remove the dead fish.

Once that is complete, McCracken said oxygen will be pumped into the remaining water in an effort to save any living fish. There will be no more flood water removal. About 260 acres of Prospect Island remain under water, according to McCracken.

http://www.news10.net/display_story.aspx?storyid=35609

 

 

Levee repairs leave fish high and dry

Fairfield Daily Republic – 11/26/07

By Barry Eberling, staff writer

 

FAIRFIELD - A U.S. Bureau of Reclamation effort to repair levees at remote Prospect Island in eastern Solano County has put hundreds of fish at risk, prompting an eleventh-hour plan to save at least some of them.

The U.S. Bureau of Reclamation in recent weeks has been repairing a breached levee at a cost of $2.5 million because of several boating accidents, bureau spokesman Jeffrey McCracken said. Boats flipped over as people tried to go through the breach and onto the flooded Sacramento-San Joaquin Delta island to fish.

'That was a liability to us,' McCracken said.

Once the breach was closed, water was trapped on the island. The bureau began pumping out the water, leaving fish some say hundreds, others say thousands to die. The bureau owns about 1,200 acres of the 1,600-acre island.

Complaints by fishing groups brought the issue into the spotlight. Now the bureau has talked to the state Department of Fish and Game about taking a new approach.

About 260 acres of the island is still flooded with water several feet high, McCracken said Monday. That water will remain for the surviving fish. Fish and Game has determined it can be fish habitat, he said.

The bureau is removing dead fish from the island to preserve oxygen, he said, and will aerate the remaining water.

'Just like a pump on an aquarium, only on a large scale,' McCracken said. 'That will clean the water up.'

Fish and Game is investigating the incident, agency spokesman Steve Martarano said Monday. It will forward the results to the state Attorney General's office, he added.

Bureau officials knew before the pumping began that the island had some fish because people fished there, McCracken said. He has heard that many of the fish are carp and perhaps striped bass, he said.

The agency consulted with the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration before doing the levee repairs, McCracken said. It approached Fish and Game to determine whether it needed a permit, he said.

'There was no practical way to salvage fish there,' McCracken said last week after the pumping began.

The levee breaks being repaired happened in January 2006, McCracken said.

http://www.dailyrepublic.com/story.php?id=101.7

 

 

Delta island could be for sale

Fairfield Daily Republic – 11/26/07

By Barry Eberling, staff writer

 

FAIRFIELD - Anyone who has a few million dollars to spend and wants to own a Sacramento-San Joaquin Delta island may soon get the chance.

The U.S. Bureau of Reclamation wants to get rid of the 1,253 acres it owns on 1,600-acre Prospect Island in eastern Solano County. If no other federal agency wants the land, it could hit the open market.

Bureau spokesman Jeffrey McCracken expressed uncertainty on how long all of this might take.

'We've never been in the selling-island business,' McCracken said. 'I wish I could answer. We'd try to get it on the market by early next year.'

The rich soil on the island makes it good for farming. A duck hunting club might locate there. Several Delta reports mention the land as a prime candidate for habitat restoration.

But be warned: Owning a Delta island can be expensive, as the bureau has found out. It bought the land in 1994 for $2.8 million.

 

According to Cal-Fed memos, it had spent more than $3.2 million by 2005 on levees repairs. A new round of levee repairs has cost another $2.5 million.

The bureau never meant to own Prospect Island for 13 years. It purchased the land at the direction of Congress as a stop-gap measure. Prospect Island was to be restored as wildlife habitat and become part of a North Delta National Wildlife Refuge run by the U.S. Fish and Wildlife Service.

But a restoration project spearheaded by the U.S. Army Corps of Engineers and state Department of Water Resources never happened. Neither did the refuge. The bureau in 2003 looked at selling the island but held onto it a little longer to see if a federal or state agency might still step forward. None has to date.

A memorandum by Lee Laurence of the bureau said the state Department of Water Resources, the Port of Sacramento and several groups and individuals have expressed interest. The Port of Sacramento already owns part of the island adjacent to the deep water shipping channel that leads to West Sacramento.


Solano County Supervisor Mike Reagan can envision the Solano County Water Agency using the island as a reservoir to store Delta water for local cities, but that idea has yet to generate widespread local support.

'We don't have a pressing need for the water now,' Reagan said. 'Fifteen or 20 years in the future, we will have.'

Otherwise, Reagan said he would like to see the land back in private ownership, with active management.

How much Prospect Island might cost remains to be seen. The federal government will have an appraisal done to determine the fair market value.

Prospect Island is near Liberty Island, which was also to be part of a North Delta Wildlife Refuge, and Ryer Island, an area in eastern Solano County that is used for farming.

The area in pioneer days was still swampy wetlands. In the early 1900s, levees were built to create dry land so that crops such as corn, safflower, sugar beets and wheat could be grown.

But the dried-out soils subsided as time went by, leaving parts of Prospect Island about 5 feet below sea level. The island has flooded several times over the years because of levee breaches, including in 1980, 1982, 1983, 1986, 1995 and 2006.

The Delta Protection Commission will get an update on Prospect Island when it meets at 6:30 p.m. Thursday at the Walnut Grove Public Library, 14177 Market St. in Walnut Grove. #

http://www.dailyrepublic.com/story.php?id=101.8

 

 

DELTA LEVEE ISSUES:

Rising sea could threaten region; Levee improvements needed by end of the century, experts say

Stockton Record – 11/27/07

By Alex Breitler, staff writer

 

A predicted sea level rise of greater than 3 feet could inundate the Delta and flood portions of west Stockton by the end of the century unless levees protecting the city are strengthened, experts say.

 

In the latest in a series of reports, an international team of scientists said this month that average sea level is rising faster today than it did in the mid-20th century and that evidence of climate change is "unequivocal."

 

Closer to home, CALFED scientists believe sea levels this century will likely rise anywhere from 2 feet, 3 inches to 3 feet, 3 inches. If ice caps melt faster than expected, a 61/2 foot rise is possible.

 

These surging seas could overwhelm 1,100 miles of Delta levees.

 

Ron Baldwin, director of the San Joaquin County Office of Emergency Services, said some levees protecting Stockton are not capable of withstanding a more-than-3-foot rise in sea levels. The good news, he said, is that there are decades to do something about it.

 

"It's kind of hard to believe that over 100 years we would sit here with the same levees and just watch the water come creeping up," he said.

 

Levee improvements will have to be made continuously for decades to keep up with the changing environment, he said.

 

Stockton engineering services manager Roger Churchwell said the city has not specifically studied the effects of sea level change. "In the future, we're going to have to look at that," he said.

 

Sea level projection maps issued by the University of Arizona suggest an increase of a little more than 3 feet has potential to flood most of the Delta and parts of northwest Stockton as far east as Interstate 5. But these maps might not consider flood-control barriers such as levees and their ability to hold back higher flows.

 

Higher sea levels mean longer, more frequent and more intense flooding throughout the Delta, scientists say. Even with a modest rise of 12 inches, high flows that to this point have been "exceptionally rare" could occur for the equivalent of two dozen days each year.

 

"It is these events that pose the greatest risk to Delta levees, infrastructure and private property," Mike Healey, CALFED lead scientist, said in a paper this past summer.

 

Sea level rise has two primary causes. Higher temperatures cause seawater to expand at the surface, and, indeed, 11 of the past 12 years have been among the warmest worldwide since 1850, the Intergovernmental Panel on Climate Change said in its recent report.

 

The melting of glaciers, snowfields and ice sheets adds even more water to the oceans. Satellite data since 1978 show Arctic sea ice has shrunk by 2.7 percent each decade.

 

Although well inland, the Delta is not immune. Scientists in October said a sea level rise at the Golden Gate Bridge would be about the same in the central Delta, although areas farther inland, including Stockton, could see proportionately smaller increases.

 

Delta islands have sunk as far as 28 feet below sea level due to farming. So as sea levels rise and the land drops, the pressure on the water side of the levees grows.

 

"(The Delta) is a very large hole in the ground," said Jeff Mount, a University of California, Davis, geologist and Delta expert. "The only thing keeping us from disaster is these levees."

 

Levees guarding urban areas such as Stockton and Lathrop are generally stronger.

 

However, "just to maintain status quo, all those levees are going to have to be raised, probably in increments," said Les Harder, a deputy director for the state Department of Water Resources.

 

The problem is compounded, he said, by reduced snowpack in the Sierra Nevada. That could mean more rainstorms washing down the mountains and overwhelming reservoirs, flooding downstream areas.

 

The Federal Emergency Management Agency is working on new maps showing which portions of San Joaquin County are in the 100-year flood plain, meaning a flood would have no more than a 1 percent chance of occurring each year. But FEMA is not considering sea level rise in its evaluations, spokesman Frank Mansell said. State officials have pushed for a higher standard of flood protection, calling FEMA's inadequate.

 

Stockton historically has not flooded from the Delta as often as from the Calaveras River or other streams draining from the east, Baldwin said.

 

"It's a risk we take living here," he said. #

http://www.recordnet.com/apps/pbcs.dll/article?AID=/20071127/A_NEWS/711270325

 

 

Editorial: A New Water Plan?; Taking the next step on the Delta

Vallejo Times Herald – 11/27/07

 

The latest proposal to save the Delta ecosystem and deliver dependable supplies of fresh water to users offers some promising ideas on the control and financing of water. It also has the advantage of tentative support of large water users and biologists. But it also appears to be missing a major essential element - storage.

 

The Bay Delta Conservation Plan would change the way much of California's water is managed. It would set ground rules for how water will be delivered and how the Delta environment would be protected for the next half century.

 

The conservation plan seeks to replace the current permit system. Water users would pay for new infrastructure, wetlands restoration and other related projects in return for guaranteed stable water supplies.

 

Certainly users should pay the full price for water supplies and delivery systems. However, part of the infrastructure called for by the conservation plan is a controversial aqueduct around the Delta.

 

This is a smaller version of the Peripheral Canal, which was defeated by voters in 1982. But unlike the 1982 canal, this one would be controlled in conjunction with the existing federal and state intakes near Tracy.

 

A canal by itself is not workable because it would not be able to take more water without violating environmental standards in the Delta.

 

However, with two intakes, a new one in the Sacramento River and the existing pumps in Tracy, there would be more flexibility in transferring water.

 

By using two spigots instead of one, water supplies could increase temporarily and fish could be more easily protected by using a second intake if fish congregated at the first one.

 

Biologists like the idea of being able to pump water from the Sacramento River because it would spare the huge numbers of fish that are killed each year at the south Delta Pumps.

 

With a coordinated control of the aqueduct pumps on the Sacramento River and the current pumps in the south Delta, water could be more efficiently directed toward users and the Delta.

 

So far so good, as far as water control and payment are concerned. But having two sources of intake using water from the same Sacramento-San Joaquin system does not create dependable new supplies in dry periods, when it is most needed. Only a significant increase in storage capacity can accomplish that.

 

It has been nearly three decades since a major new reservoir was built. In the meantime, California has grown by 15 million people.

 

More efficient use of water and less water-intensive agriculture have served the state well. But there are limits to such measures, especially if we experience another drought and add a half million people a year to the states population.

 

If sufficient water supplies are to be guaranteed for agriculture, urban users and the Delta environment, at least one major new reservoir will be needed. Without new storage, farmers are not likely to have sufficient supplies in dry years.

 

Also, higher salinity levels in the Delta could adversely affect the water quality for the 500,000 people in the Contra Costa Water District.

 

The Bay Delta Conservation Plan should be seen as a major first step in reforming the way water is allotted, delivered and financed.

 

There is good reason to move ahead with it, particularly if major water users, biologists and environmentalists concur.

 

However, there has to be a second step, one that also should advance as soon as possible, and that is construction of a reservoir large enough to provide sufficient volumes of fresh water to keep the Delta healthy and adequately supply all users in dry months and droughts. #

http://www.timesheraldonline.com//ci_7570637?IADID=Search-www.timesheraldonline.com-www.timesheraldonline.com

 

 

INVASIVE SPECIES:

Snails pose threat via Lake Natoma trout hatchery; Tiny invasive species can travel inside fish, infest more waterways and destroy food source

Sacramento Bee – 11/27/07

By Matt Weiser, staff writer

 

A tiny but tough and very hungry foreign snail has invaded the American River, prompting concern that waters throughout the state could become infested if it gains a foothold in the river's trout hatchery.

 

The New Zealand mudsnail has been confirmed in two locations on the river this month, both below Lake Natoma. On other rivers, the snail has been known to carpet the river bottom at more than 500,000 per square meter, and it could devour food available to native fish in the river.

 

But officials are equally concerned about preventing the snail from being transported by human activity above Nimbus Dam and into Lake Natoma, the water supply for the state's American River Trout Hatchery.

 

The tiny snail – less than 5 millimeters long – can survive in the stomachs of fish for up to three days and be excreted alive into new waters. So the millions of trout transplanted from the hatchery each year to lakes throughout the state could spread the snail far and wide.

 

"It's our top priority to ensure that does not occur," said James Navicky, an environmental scientist with the state Department of Fish and Game.

 

"It could be a relatively simple thing to move the snail above Nimbus. We're going to have to really step up what takes place here."

 

Fish and Game officials last week held an emergency meeting to discuss the problem, Navicky said, and immediately adopted new monitoring procedures to detect the snail at the hatchery.

 

The snail is primarily transported by attaching itself to people and their equipment, and officials urge the public to help prevent its spread.

 

Fishing waders, boats and other aquatic gear should be frozen overnight or vigorously cleaned and dried before moving between the lower American River and Lake Natoma or any other water body.

 

The snail can survive out of the water for up to a month on a boot sole or a boat's hull. So the cleaning must be thorough.

 

Gary Eblen, owner of American Fly Fishing Co. in Sacramento, said this will be an uphill battle because of the "unbelievably heavy" human traffic in the American River Parkway. It is probably the most heavily populated place infested by the mudsnail in California, if not nationwide.

 

Signs have been posted along the river for years to warn anglers about transporting mudsnails. Yet they arrived anyway.

 

"You've got everybody and their uncle out there fishing. Some of them care. Some of them don't," said Eblen. "Stopping it is going to be a massive and difficult effort."

 

The New Zealand mudsnail was discovered in the United States in the late 1980s in the Rocky Mountains. Its first California appearance came in 2000 in the Owens River, east of the Sierra Nevada.

 

The snail leaped the range three years later with an appearance in Putah Creek in Yolo County, and is now found in eight locations west of the Sierra.

 

In the American River, it was found Nov. 12 about a half-mile below Sunrise Bridge by Ken Davis, an independent aquatic biologist based in Sacramento; then on Nov. 14 at San Juan Rapids by Mike Healey, a fisheries biologist at the Department of Fish and Game.

 

"They are reproducing," said Davis. "Everything is there for them to prosper."

 

Navicky said the effect on the river's primary native fish – salmon and steelhead – might not be severe. That's because these fish are migratory, spend most of their time in other places, and don't feed much when they return to spawn.

 

But the snails have the potential to upset the entire food chain in the river.

 

"It's suspected they can have severe ecological impacts in the waters where they're found, but that's an area where we need more research – in the U.S. in general, not just in California," said Denise Walther, assistant aquatic invasive species coordinator at the U.S. Fish and Wildlife Service office in Stockton.

 

The snails are prolific and can spread quickly in a watershed. On Putah Creek, they were first found just below Monticello Dam at Lake Berryessa in October 2003, and are now throughout the creek as far downstream as Pedrick Road, a distance of more than 12 miles. Some spots now host more than 100,000 snails per square meter.

 

There is no practical way to eliminate the snail once it becomes established. Evidence suggests, however, that they don't like fast water, which may help limit their spread in the American River.

 

If the snails enter Lake Natoma, research from other locations indicates they could be controlled by water filtering systems or new water treatment steps.

 

This would add expense and time to the hatchery process.

 

"It's going to have an impact one way or another. It's not good," said Davis. "At this point, rather than try and guess what's going to happen, we emphasize that people clean their equipment no matter what river they're in." #

http://www.sacbee.com/101/story/523061.html

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