Number range CHAPTER © 2003 by Leo Poppoff

August 28, 2003

Basin Watch

by

Leo Poppoff

AFTER LEARNING HOW MUCH POLLUTION TO CUT, WHAT'S NEXT?

For the next couple of years, researchers from universities, research
institutes and government agencies will continue to develop a TMDL
(Total Maximum Daily Load) for Lake Tahoe and its watershed. That,
basically, means that they're working to determine how much current
pollutant loads to the lake must be reduced to regain some of its former
clarity. They're developing a model to calculate how lake clarity will
change as pollutant loads are varied. Researchers are also developing a
watershed model and an atmospheric deposition model. These will be able
to describe the kinds and quantities of pollutants that could flow or
fall into the lake.

All this is geared to provide Basin resource managers with tools to make
informed decisions about how to stem the deterioration of Lake Tahoe.
According to estimates, restoration of the lake and watershed will cost
more than a billion dollars -- a healthy sum. It's important to use that
money wisely. It would be discouraging, to say the least, to find that
we haven't achieved restoration goals after spending such a big chunk of
taxpayers' money.

By 2005, when the clarity and watershed models are complete, resource
managers will know what an acceptable loading to Lake Tahoe should be.
And, they'll have a good idea of the current pollutant loading to the
lake. Then, they can decide how much it must be reduced.

With that information, TRPA, California's Lahontan Water Quality Control
Board, and Nevada's Department of Environmental Protection will be able
to establish realistic water quality standards. This is a big step
forward.

Yet, it will get us only part way to the goal post. Folks will still
need to identify load reduction possibilities, decide where in the
watershed pollution needs to be controlled, and how best to do it.

The lake clarity model will tell us that to restore the lake to a
certain condition, the flow of phosphorus, nitrogen and fine particles
must be reduced by a certain amount. The model will be able to supply a
matrix of possibilities for how much each pollutant must be reduced. For
example, to get back to the 1970 clarity of 30 meters within 30 years,
the model might specify that the clarity goals could be achieved if all
the nitrogen, or all the phosphorus or all the fine particles were
removed.

But, it's not possible to eliminate all of any one pollutant. So, the
model will also provide alternative mixes of those pollutants that will
produce the same results. With that spectrum of possibilities, resource
managers can develop various scenarios for where and how pollutants can
be reduced.

One scenario could show that clarity goals can be achieved by reducing
pollutant loads equally from urban runoff, atmospheric deposition,
streams, ground water and forested areas. Still, project designers might
find that it's more cost effective to reduce more of the urban runoff
load, and less of the ground water load. Or some other combination might
be even better. Much will depend on the cost of projects and the
availability of funds.

Armed with model results, resource managers can develop plans to achieve
their goals. These plans would also include a construction schedule to
attain desired clarity goals with whatever funds are available each
year.

With the implementation plan, resource managers will identify indicators
to be measured and monitored to see how effective restoration projects
are, and effective they are over the long haul. If the projects aren't
working well, engineers and scientists will analyze the problems, make
improvements and continue to monitor them. Research and development of
pollutant control techniques continues all over the country. New
information might be incorporated in new projects and older ones might
be retrofitted. This is called adaptive management, and it's an
important element of a successful lake and watershed restoration
program.

Well, all this sounds very hopeful. But, there's a catch. Current
funding will probably cover the modeling efforts. But the follow-on, the
development and implementation of restoration plans, evaluation, and
potential improvements, are not currently funded.

Sure, projects will be built. There'll be money for that. But, will they
be placed in the best spots, and will they be as effective as hoped for?
Certainly, a billion-dollar project deserves the kind of planning
envisioned by the TMDL team.

There are some prospects for funding, according to Dave Roberts, who
leads Lahontan's Tahoe TMDL project. Still, current prospects fall short
of what's needed. And, Roberts adds, "without adequate funding, the
degree of public participation in this process will be much less than it
should be."

How important is the follow-on work? "I think it's absolutely critical
for the success of the project," Roberts explained. "It's one thing to
know that the problem is this big. The real question is this: how do we
take advantage of these tools to begin to solve that problem?"

So, will we make a touchdown, have to make do with a field goal, or be
forced to punt?

Send comments to
[[basinwatch@sbcglobal.net]{.underline}](mailto:basinwatch@sbcglobal.net).
(This is a new email address).