Sean Kimbrel - As sediment accumulates in a reservoir, the capacity of that reservoir
decreases.
To meet various demands and beneficial uses, such as for water supply, and hydropower generation
Paul Boyd – Reservoir sedimentation is a chronic issue.
It will affect all reservoirs sooner or later.
It’s simply a matter of time.
In some cases, that may be a few decades.
In some cases, it may be hundreds or thousands of years.
Dr. Tim Randle – Sedimentation is affecting the project benefits for the nation’s reservoirs.
It’s by filling up these reservoirs gradually, over time, reducing the storage capacity,
impairing outlets, impairing boat ramps, marinas, impairing space for recreation, and we need
to look at ways to better manage sediment over the future more sustainably.
Paul Boyd - The sedimentation rate that we see in the reservoirs is driven by one: the
weather patterns, two: the geography associated with that reservoir.
When we have reservoirs in areas that have high rainfall, steep mountain valleys, a high
amount of sediment available to come run off the watershed… all of those things contribute
to high loads that can result in accelerated loss of storage volume.
Sean Kimbrel – Current methods to measure a reservoir’s sedimentation are done in
two ways.
The first is direct measurements, where you have a boat with a depth sounder and GPS mounted
to it to map the bottom of the reservoir, and then you compare that map that you’ve
created to an older survey.
The second way to measure reservoir sedimentation is indirectly where you’re using modeling
techniques, whether it’s an empirical type of model, or an analytical, or even physically
based model to indirectly estimate the amount of sediment accumulation in a reservoir.
Tim Randle – One of the biggest limitations is just our capacity to do it.
There’s three hundred and some reservoirs in Reclamation’s inventory… many more
when you look at the full federal sector, and private as well, and there just haven’t
been that many surveys largely due to cost.
Paul Boyd - These traditional methods require
personnel on the ground to do that, and to get to these remote areas, and as budgets
are limited, we try to be the best stewards of the resources we can.
We have to make tradeoffs.
For indirect methods, the limitations are simply that our estimate is based on the quality
of the data that’s available to either do numerical modeling or watershed runoff estimates.
Sean Kimbrel – So what we’re looking for, in terms of an improvement, and the indirect
estimates of reservoir sedimentation volume is certainly perhaps a model or a method that
is relatively more accurate, and less time consuming for us to be able to estimate the
accumulation of sediment in unsurveyed reservoirs.
Tim Randle – And so if we can come up with less expensive ways of doing the survey, or
estimating, in lieu of the surveys, what that sedimentation rate might be, that would be
quite helpful for water resource managers: knowing how much water is actually being stored
in the reservoir.
Paul Boyd – The prize challenge allows us to query literally hundreds of millions of
people to come up with good ideas.
Tim Randle – The exciting thing for me about a prize challenge is you get lots of people
involved.
There’s always somebody out there with a wonderful idea, and they just need to be asked
to give some time to think about it.
It’s an opportunity to adopt that idea, give that person some credit, and maybe some
cash money.
Paul Boyd – So, we’re partnering with Reclamation because we both have the same
needs; we both have data gaps that we’d like to assess because we both feel that it’s
very important to establish where we are right now… look at our resource availability,
and then look into the future and say, “What’s going to happen to that resource?
Will we be able to provide benefits in the future, and if not, what action can we take
now to preserve those benefits in the future?”