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rivrrts429
04-22-2007, 04:01 PM
The Press-Enterprise
When you're trying to stay fresh as rain while being undermined by algae and carp, a breath of fresh air could be just the recipe for keeping the green water and the swampy stink at bay.
That's the plan behind a $2.4 million network of air compressors and underwater pipelines being installed at Lake Elsinore, where the infusion of oxygen will control the growth of algae and stunt environmental chain reactions that affect everything from the color of the water, to the type of fish that thrive there, to the amount of plankton that fish eat.
This "diffused aeration system" will go into operation late next month. To mark the occasion, the Lake Elsinore & San Jacinto Watersheds Authority will hold a dedication ceremony on May 31 at the city marina.
Silvia Flores / The Press-Enterprise
Leo Solorzano, the city of Lake Elsinore's lake and aquatic resources supervisor, looks over Lake Elsinore from one of two buildings that each house two air compressors that will pump air into the lake through pipelines. The purpose is to control algae growth in the lake.
"This is ... just like the diffuser in your aquarium," said Mark Norton, administrator of the Lake Elsinore & San Jacinto Watersheds Authority.
"It's not going to be like a Jacuzzi," added Pat Kilroy, the city's director of lake and aquatic resources. The aeration system will create "gently rolling bubbles coming up from the bottom of the lake," he said. "This will probably be one of the largest lake aeration systems in the U.S."
Four air compressors, each with a 200-horsepower engine, will pump air into the lake through 4,000-foot-long pipelines that fan out from the machines like fingers.
Two air compressors are housed together on the north side of the lake, near Lakeshore Drive, and the other pair is being installed on the south side of the lake, near Grand Avenue. Each compressor can pump 1,000 cubic feet of air per minute into the lake. The 12 pipelines, made of polyvinyl chloride -- commonly known as PVC -- are perforated for the last 2,500 feet, so the air will be injected into the water in a long stream, not just at the mouth of the pipeline, Norton said.
"We really want to get the air toward the deepest parts of the lake," said Kilroy, noting the water is about 27 feet at its deepest point.
The amount of oxygen in the water is vital to the aquatic health of Lake Elsinore because it affects the delicate balance of the lake's plant and marine life.
"The oxygen wasn't getting down to the deeper levels where the fish are," Norton said.
Every spring, the authority removes carp, a nonnative fish, from the lake. "They're sent out to the Coachella Valley, where there's a processing plant that turns them into fertilizer," Norton said.
Since 2002, the authority -- under a contract with the city -- has removed about 1.5 million pounds of carp from the lake, he said.
"Carp are an undesirable fish," Norton said. "There aren't many people who like to eat them. They're not considered 'game fish.' "
More importantly, the bottom-dwelling carp stir up silt and nutrients on the lake floor, and that spurs the growth of algae. Too much algae in the lake lowers the oxygen levels in the water, sometimes beyond the level that fish can survive.
As a result, under those conditions the carp and other fish die off on their own.
Such "fish kills," coupled with the mossy tint and marshy smell that too much algae can cause, make the lake undesirable to boaters and recreational users.
Pipelines such as these are part of a $2.4 million network of air compressors and underwater pipelines being installed at the lake.
"People don't like to use the lake when it's really green. Plus, it gives off odors when (algae) starts to die off," Norton said. "Sometimes on hot days, it can get particularly pungent."
Along with removing excess carp, the city and the authority turn to Mother Nature's food chain -- and a local fish farm -- to help keep the lake in balance.
"We put 4,000 pounds of hybrid striped bass into the lake. These bass feed on the 'fingerling' of the carp -- the small baby carp," Norton said.
The bass also eat a fish called threadfin shad. The shad are a villain in the lake's ecology because they consume a microscopic organism called zooplankton -- and zooplankton's favorite meal is algae, Norton explained.
Too many shad equals too little zooplankton. Too little zooplankton equals too much algae.
Another reason the authority stocks the lake with hybrid striped bass is because they serve their carnivorous duty and are a desired catch for anglers, but they do not breed, Norton said.
"You can still eat them. They just don't have the capability to reproduce," Norton said.
The hybrid also are preferred because of concerns by the California Department of Fish and Game that, in the event of a heavy rainstorm, the carnivorous bass could be swept downstream and wind up in other lakes and rivers, where they would eat the native vegetation and marine life.
Meanwhile, normal evaporation makes the lake's depth level fluctuate throughout the year. On average, Kilroy said, "we lose 9,000 gallons a minute. So every two minutes, you lose a good-size swimming pool," he said.
"Typically, we lose about 4 ½ feet per year due to evaporation," Kilroy said.
The 3,000-acre lake is fed by runoff from mountain streams and the San Jacinto River.
To offset the evaporation loss, the Elsinore Valley Municipal Water District is working on a project to bring recycled water from its treatment plant through a pipeline that will empty into the lake, Kilroy said.
The treated water "is highly filtered," Kilroy said, noting it meets state sanitation standards and is probably cleaner than ocean water.
As for the diffused aeration system, the cost of building it -- and other lake improvement projects -- was covered by $15 million that Lake Elsinore received from a state water bond approved by voters in 2000. The city, Riverside County and the Elsinore Valley Municipal Water District will share its annual operation and maintenance costs, each contributing $100,000 per year, Kilroy said.

phebus
04-22-2007, 04:03 PM
Now it can look like boiling stew :idea:

Jyruiz
04-22-2007, 04:10 PM
Yes.

BoneDaddy
04-22-2007, 05:17 PM
I am glad that action is being taken. It seems like it has been in the works for years. We have been hearing that this was going to happen for a very long time.
Unfortunately, if this all works and the water gets cleaner then I will have to start sharing the lake. It has been very nice to go to Lake Smellsmore for a quick test run or a wake board trip and have nobody on the lake. I'd swim in it now but I don't think I would eat a fish from it......:D

rivrrts429
04-22-2007, 05:27 PM
I couldnt agree more, as long as they're trying to do something to improve the soup the city is moving in the right direction. I sure hope it works and boosts the lakes image.
Oh...and eating a fish from there? HELL NO!!!

boats&bars
04-22-2007, 05:56 PM
it is still cleaner than Perris.

slotracer
04-22-2007, 05:57 PM
they just started this in the stockton deep water channel. time will tell if it works or not.

mickeyfinn
04-23-2007, 06:08 AM
I don't know how large this lake is, but aeration will help control the problems if they add enough oxygen. The real problem in this kind of a lake is usually traceable back to discharges in the lake that are high in nutrients such as ammonia or phosphorus, particularly phosphorus. These nutrients become entrained in the silt on the bottom of the lake and serve as a constant nutrient source for the algea. The best way to attach the problem would be to dredge the silt from the bottom and remove as much of the nutrients as possible. This problem is very common in smaller man made lakes constructed mainly for fishing. The DNR handbooks will encourage "fertilizing" a lake in order to promote fishing. The algea presents a problem in terms of color and odor, but actually increases the number and size of fish in the lake until it get to be oxygen depleting. Whether it actually helps or not will depend on the quantity of oxygen being pumped into the water and whether it is being delivered to the right place.

C-2
04-23-2007, 06:29 AM
I don't know how large this lake is, but aeration will help control the problems if they add enough oxygen. The real problem in this kind of a lake is usually traceable back to discharges in the lake that are high in nutrients such as ammonia or phosphorus, particularly phosphorus. These nutrients become entrained in the silt on the bottom of the lake and serve as a constant nutrient source for the algea. The best way to attach the problem would be to dredge the silt from the bottom and remove as much of the nutrients as possible. This problem is very common in smaller man made lakes constructed mainly for fishing. The DNR handbooks will encourage "fertilizing" a lake in order to promote fishing. The algea presents a problem in terms of color and odor, but actually increases the number and size of fish in the lake until it get to be oxygen depleting. Whether it actually helps or not will depend on the quantity of oxygen being pumped into the water and whether it is being delivered to the right place.
Good observation:)
Elsinore is one of only 2 or 3 natural lakes in Cali (before the levee was built). It's also old...like really old and they estimate the silt is about 20' thick, so dredging will never work. I've alsways wondered if they could make a new bottom with pea gravel?
About ten years ago they had a company running around with a pontoon, just filtering water with some type of copper filter, which broke the phosphourous/nitrate chain - the lake was actually clean and you could see the bottom.
I'm sure there is an answer, afterall, it's a large fish pond. But as any reefer knows, you can have as many cutsie bubble generators as you want - but it's surface agitation and trickle-style filtering which puts oxygen in water by artifically increasing the surface area, and thus increasing the surface oxygen transfer. One little bio ball increases surface area by a yard square...so maybe they are trying to duplicate something similar? For the non-reefer, think of it in the same terms as saltwater tanks - most have no bubbles, but there is oxygen being delivered to the water.

moneypit
04-23-2007, 06:46 AM
I think its great but at the same time wonder how is it that California nearly couldn't afford to keep an ready active and clean like Castaic open a few years ago. There was a lot of talk and sigantures sent out to the state capitol regarding the lake almost being shut down. They couldn't afford to pay to have staff there...
Then you hear about this...

Desert Rat
04-23-2007, 10:26 AM
At least now when it smells like a fart it will have the visual affect to go along with it:jawdrop: http://www.dodgeintrepid.net/forums/images/smilies/fart.gif