Archive for Sunday, September 19, 2010

Water worries

Legislature must come up with long-term, workable solution to sedimentation in state reservoirs.

September 19, 2010


The recent musty-tasting drinking water in Lawrence has, for the most part, dissipated. And while experts say such water problems don’t pose health risks for humans, there is great reason for concern about the future of the water supply in Lawrence and throughout much of Kansas.

Blue-green algae blooms, fueled by nutrient-rich sediment that is flowing into Kansas reservoirs, caused our patchouli-tasting water. Other communities in the state experienced similar problems this summer.

Lawrence draws its drinking water from both Clinton Lake and the Kansas River. And while Clinton Lake wasn’t the culprit in this summer’s musty water, it is filling up with sediment at a much-faster rate than originally predicted.

The city’s problems with algae this summer started miles upstream north of Manhattan — in Tuttle Creek Reservoir, which is about 50 years old.

This cycle of increased sediment and nutrients and more frequent algae blooms shows no sign of slowing anytime soon, according to the Kansas Biological Survey.

“You’re not going to see it improve because the water body holding it is an aging reservoir, filling with nutrients and filling with sediment,” Don Huggins, an aquatic ecologist, told the Journal-World.

As more sediment flows into reservoirs, more algae blooms can be expected. And left unchecked, the reservoirs will simply fill with silt.

The U.S. Army Corps of Engineers believes it can better control algae blooms. But it’s an involved process — and likely a costly one — that would include limiting erosion, animal waste and fertilizer that enter our waterways.

And, ultimately, experts predict that the state’s reservoirs must be dredged to rid them of silt. Another possibility is to construct new reservoirs.

No solution is cheap. In fact, the costs are extraordinary.

State officials have been aware for years that the sediment problem is growing and that extremely costly answers are looming on the horizon.

During the 2009 session of the Kansas Legislature, a Kansas Water Office official estimated it would cost $500 million to construct a new dam the size of Clinton Lake’s. That same official said the state needs $75 million — each year — to maintain current dams.

In sound economic times, those numbers seem astronomical.

But the problem — regardless of whether the state is in a recession — will not evaporate.

So the Legislature must agree to finance a long-term, workable solution. If not, a little musty-tasting drink of water will be nothing but a fond memory.


LogicMan 7 years, 7 months ago

It's simple, but messy.

Drain and shovel it out, or dredge. Start now.

ralphralph 7 years, 7 months ago

Thank you, LJW, for finally "naming names". I had read several items in several places that mentioned the algae problem was in a reservoir, but never did anyone way which one. I imagined Tuttle was it.

This is a real problem, and yet another that has resulted from Federal Government action without thinking and planning ahead. Some folks in the fifties fired-up their slide rules and decided how long the reservoirs would take to fill in, likely accepting their own findings from The Theoretical World without ever having gone out into the field and researching what happens in The Real World. Guess what? They were wrong. Surprise!

In the meantime, anyone who has gone to these reservoirs - particularly the ones in flatter areas, like John Redmond (which averages about, what, 2 feet in depth) - could see, without knowing anything about math or engineering or geology or hydrology, etc., that these suckers were plugging up fast. The response: no response.

The Federal Government likes to receive Glory in return for its spending. There is no Glory in routine preventive maintenance. The Glory is in building Engineering Marvels and in Saving the People when things have gone completely down the tubes. Nobody loves a guy who takes care of stuff and socks away money over time for the big projects they'll need to do.

Prediction: We'll have to just let the reservoirs go completely to hell, so the Federal Government will find the requisite level of Glory available to fund the reclamation. In the interim, things will get more stinky and foul-tasting. Encourage your legislators to get their White Hats blocked, so they'll look sharp riding in to rescue us.

Idea: Got Infrastructure Projects? These projects could go a long way towards providing stable employment for illegal aliens who are struggling in the ailing underground economy.

EAStevens 7 years, 7 months ago

How about more info on the solution noted by the Army Corps of Engineers -- that is, "limiting erosion, animal waste and fertilizer that enter our waterways"?

Addressing the source of the problem -- rather than fixing only its effects -- will address other water-related problems, ranging from little creeks that no longer do their job of filtering water and helping to reduce flooding, to rivers that are full of manure and fertilizer runoff, to the health of the Gulf of Mexico where sedimentation and algae bloom is a colossal, marine life-threatening problem.

Richard Heckler 7 years, 7 months ago

Areas are experiencing tremendous growth as more people choose to live away from large urban centers. As a result of this growth, critical shoreline buffers are being lost. Shoreline buffers are the last line of defense in preventing nonpoint source pollution. Combined with discharges from municipal waste treatment facilities, the potential exists for a deterioration of water quality.

Richard Heckler 7 years, 7 months ago

Wetlands Impact on erosion and sediment

Erosion Control During a storm, the effects of rushing water can be very destructive. Fast-flowing water can carry a large load of soil particles from the land which are then washed into lakes, rivers, and streams. Excessive sediment in water is considered both a chemical and physical pollutant; it can carry bacteria and toxic particles and can alter the habitat of the receiving water for plants and animals.

  Wetland vegetation reduces the erosive effect of rushing water by slowing the velocity of
  floodwaters, binding the soil with its roots, and causing suspended soil particles to settle
  out before they reach open waters. Coastal wetlands also protect shorelines from erosion by dissipating the energy from waves and currents.

Sediment Trapping Water flowing into wetlands slows down dramatically as it comes into contact with wetland vegetation. Suspended soil particles or sediments will settle out of the water and bind to the stems and roots of plants. The role wetlands play in trapping excess sediments and preventing them from entering river and lake systems is important for a number of reasons: 1. sediments accumulating at the bottom of streams and lakes can smother fish spawning areas and bottom-dwelling aquatic life; 2. wetland filtering reduces siltation of ports, harbors, rivers, and reservoirs, saving a lot of money that would have to be spent on dredging or removing the sediment; he forested wetlands along the Alcovy River in Georgia significantly improve stream water quality affected by wastes discharged upstream. An equivalent amount of pollution removal in a sewage treatment plant would cost $1million each year. 3. sediment particles are often vehicles for transporting pollutants such as nutrients, pesticides, and heavy metals.

Studies have shown that as much as 80-90% of sediments in the water column
may be removed as they move through wetlands!

Flap Doodle 7 years, 7 months ago

You are forgetting that attribution things again, merrill. Plagiarism makes the Baby Al Gore cry.

Richard Heckler 7 years, 7 months ago

Thanks for asking....

Wetlands can improve your drinking water, agricultural operation and land value:

Flap Doodle 7 years, 7 months ago

Could just saved us the time. Is that going into your regular rotation of posts?

Richard Heckler 7 years, 7 months ago

The problem is that much of that suspended sediment never reaches the sea because it gets trapped by thousands of dams—a situation that will only get worse if the construction of dozens of large dams in developing nations around the world goes ahead as planned.

Going down? Reidy and her colleagues recently tallied the dams on the world's large river systems—systems that, if undammed, would have an average flow rate of 350 cubic meters per second in at least one place along the river or its tributaries. The 292 rivers meeting that criterion drain more than 54 percent of the world's land surface and carry 60 percent of the world's river flow. The researchers couldn't find reliable data, and so didn't consider, rivers in much of Indonesia and part of Malaysia, says Reidy.

Flow in 172 large river systems—more than half of the systems that the researchers studied—is substantially affected by dams, Reidy and her colleagues report in the April 15 Science.

When dams reduce suspended sediment at a river's mouth and beyond, some benefits can accrue. Harbors may not need to be dredged as often, and in the less murky waters, offshore coral reefs may receive more sunlight.

On the downside, however, the reduction of sediment flow, however, contributes to subsidence and loss of land in many river deltas, says James P.M. Syvitski of the University of Colorado at Boulder. Along Spain's Ebro River delta, for example, engineers have trucked in more than 110 million tons of sediment since 1983 to replenish beaches. The Ebro and its tributaries have 187 dams that trap about 99 percent of the sediment that would otherwise reach the delta.

Likewise, dams along the Nile interrupt the seaward trek of about 98 percent of the river's suspended material. At the mouth of the Nile, the coastline is retreating by about 10 m each year, Syvitski says.

Drops in sediment flow exacerbate a variety of problems beyond loss of coastal lands. For example, carbon-rich material in sediment nourishes organisms at the base of the food chain in estuaries and near-shore waters. When those small animals become scarce, larger creatures that dine on them go hungry. The sardine catch at the mouth of the Nile plummeted 95 percent after the Aswan Dam, completed in 1970, began intercepting nutrient-rich sediment destined for the Mediterranean, says Syvitski.

Similarly, the shrimp catch in Mexico's Gulf of California dropped significantly when dams along stretches of the Colorado River in the United States began operation in the mid-20th century.

In some locales, accumulating sediments serve yet another purpose: They bury pollutants that people have generated near the shore. The faster silt and other material collect on the seafloor, the more quickly toxic materials can be isolated from the food chain, says Syvitski.


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