A daily compilation of significant news articles and comment
July 2, 2008
3. Watersheds –
State to monitor Bay halibut
Contra Costa Times- 7/1/08
Hopes of finding water trove under Montara dry up
Contra Costa Times- 6/30/08
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State to monitor Bay halibut
Contra Costa Times- 7/1/08
The state Department of Fish and Game on Tuesday announced more monitoring and other efforts in the
The changes are due to the high number of the fish being caught this season, which some say is the best halibut season in more than a decade.
"Although there is no indication that the halibut fishery is not sustainable, additional scientific data will allow us to better assess how the species should be managed, particularly in booming population years," said department Director Donald Koch.
Paul Reilly, a senior marine biologist for the department, said the department usually does such work but that the time frame was moved up because of the large amount of halibut being caught.
The department, which normally tracks lengths, weights — and, when possible, ear bones that determine a fish's age — from commercial West Coast fishermen, had started those efforts with halibut in the San Francisco Bay area last year. It did not have anything to do with this season, but it will be increased in light of it, Reilly said.
Also, the department will increase its survey of fish caught by recreational anglers — which make up the majority of halibut caught locally. The effort, in which workers go to piers, boat launch ramps and other areas to collect information, did not have a big focus on halibut before this season. It will include going to places not surveyed before.
The department is also fishing for halibut on its own, recording where on the body they were hooked and then monitoring them alive at a local aquarium to see if different hooking methods make a difference in mortality. Halibut must be 22 inches long to keep, with undersized fish required to be thrown back.
Reilly said this effort was already planned, but the importance grew with the high number of halibut being caught this season.
Later this year the department will start a statewide assessment of the size of the halibut population — that move had already been planned before this season.
Reilly said this year's good season is likely due to favorable conditions four years ago, when the halibut now reaching legal size were born. He said it's not clear what those conditions were, but temperature is likely one. He said conditions under El Nino usually mean good seasons for newly hatched fish.
Halibut larvae may be transported to
In 2004, the National Oceanic and Atmospheric Administration declared a weakened state of El Nino, which is associated with changes in sea surface temperatures in the tropical
Reilly said halibut numbers for this season are not in and there is not a lot of data on the fish from previous years, making it hard to compare this season to the past. He said besides there being more halibut around, another reason more are being brought in is because of the salmon season closure. That has more fishermen in boats catching halibut who would normally be after salmon.
"We wouldn't have nearly as much effort on halibut if the salmon season wasn't closed," Reilly said.
Berkeley Charter Boats, which handles business for six charter boats out of the Berkeley Marina, had recently been reporting this season as the best in 10 to 15 years, with boats averaging two fish per person on all-day trips. The limit is three.#
http://www.contracostatimes.com/environment/ci_9759280?nclick_check=1
Hopes of finding water trove under Montara dry up
Contra Costa Times- 6/30/08
By Julia Scott
MONTARA —If just one word could be used to describe Devil's Slide in winter, it would be "wet."
When workers attempted to stitch the sagging road together by drilling metal cables into the mountainside in 2006 — the ninth repair in 70 years — they were doused with cannonballs of muddy water trapped between the rocks.
These facts gave the Montara Water and Sanitary District hope that, once the Devil's Slide bypass tunnel project got underway, tunnel workers might discover vast troves of water stored deep in the tunnel rock bed — usable water that could alleviate the water crisis the district has faced since the 1970s.
Unfortunately for the district, and particularly for a group of Montara and Moss Beach residents who have been drawing on unpredictable backyard wells for decades, the twin tunnels being bored straight into the granite heart of Montara Mountain have turned up less water — far less water — than anyone anticipated.
According to a recent assessment by Devil's Slide tunnel project manager Skip Sowko, the largest volume of water discovered so far at about a quarter of the way into the tunnels is 7.92 gallons per minute (or 30 liters per minute). A typical person in the shower uses six gallons of water per minute.
"It's a pleasant surprise because it would be difficult for us if it were on the higher end," Sowko said.
The state Department of Transportation pumps all the water it finds into storage tanks. The silt and clay must be removed before the water is discharged into the ocean.
It is still possible, and even likely, that work crews will discover a higher volume of water as they bore northward through the mountain toward Pacifica, where less-pervious rock surfaces may spill more water when cracked open, according to Sowko.
The North Coast County Water District, serving
These details came as news to Montara Water and Sanitary District General Manager Clemens Heldmaier.
He said his agency still considered the Devil's Slide tunnel a potential new source of water, along with exploring for new wells, adding a recycled water plant, or building a water desalination plant.
"At this point we are not in contact with Caltrans and we don't know whether there is any water," Heldmaier said. "If there is water available, of course, we would be interested in knowing about it."
The Montara water district had good reason to be hopeful back in 2005, when a report prepared by several Caltrans consultants predicted water flows as high as 118 gallons per minute based on test holes drilled near the future tunnels' south entrance.
The discrepancy is not that unusual, according to Sowko. Rock type and density can vary within a few feet, which means that the amount of water trapped inside is also extremely variable. Workers will bore through several rock "faults," or areas of rock variation, as they go from south to north.
The work area closest to Montara is composed entirely of quartz diorite, or granite, which contains more cracks that allow groundwater to flow westward and escape toward the ocean.
By contrast, the rock at the center of the mountain, composed of fine-grained sandstone and claystone, contains fewer cracks and therefore holds water back more easily. But those stores of water will taper off quickly as well once they are exposed, Sowko said.
When the whole Devil's Slide project is completed in 2010, he expects the average flow from both tunnels to even out at 13 gallons per minute.
"We know that there's higher flows on the north end from our exploration. We don't necessarily know how it's all connected. If you penetrate it and you hit a high zone where there's pressure, you can bleed those out."
The North Coast County Water District will wait until workers push another 500 feet into the mountain before conducting its own study to determine how much water is available, said district General Manager Kevin O'Connell.
Most importantly, officials will have to determine the costs and benefits of building a water treatment plant at
O'Connell reached out to the Montara water district with a proposal to split the cost of building a plant two years ago but was turned down.
North Coast County Water is working out the final details on a contract with Caltrans to ensure that the tunnels will have a reliable emergency water source, according to O'Connell.
He said the pipelines that would be extended into the mountain also could conceivably be used to transport excess groundwater back to the district someday.
"We need to know exactly what's in the water and we need to know exactly how much water we're going to have," O'Connell said. "If we have to do a lot of treating we don't know how much it would cost — it could be much more than we could afford."#
http://www.contracostatimes.com/environment/ci_9747980
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