There aren’t very many issues of the Fargo Forum lately in which something about the diversion doesn’t come up – cost, who it may adversely affect, and such. In all the discussion over the past couple of years, I have never heard discussion resembling an idea I have wondered about. The recent series of articles on water in North Dakota in the Forum got me to thinking about it again. The discussion has always centered on how to move or direct water laterally – north, south, east, west – and/or retention with later release, again laterally. I wonder if straight down might be a feasible direction?
I don’t know what aquifers are below Fargo in the bedrock but what amount of holding capacity might be down there? I am wondering if a system of, what to call them, reverse wells could be placed strategically such that a portion of the water could be diverted straight down during flooding; these locations would be at low spots that flood during minor events with the reverse wells elevated enough that they are called into action only during more serious events. I’m thinking of, let’s say, a 4 foot diameter hole drilled with PVC casing down to the bedrock, backfilled with large stones for support. To filter contaminants, a charcoal layer can be placed on a screen near the top that would filter the water on the way down; after a flood, that layer could be replaced with new. At the top would be some kind of cap that could filter out mud; this might easily clog so some kind of pump would need to be located by it that could aerate the filter and keep it clear. It doesn’t seem this would cost an exorbitant amount; high pressure water could “drill” the muck we live on while sections of PVC are fed in at the same time.
I’m not an engineer so I don’t know if it would work like this but if one reverse well could put several cubic feet of water downward at the same pace the same number of cubic feet of water would pass Fargo in the Red, that’s that many less cubic feet that have to go through the channel while all the other “cubic feet” are trying to get through the channel at the same time. I keep thinking of the channel in cross-section: if we cut out one square foot of water that is going down a reverse well, what if we had 500 or 1000 reverse wells, each taking a square foot of water out of the channel? Spread back and forth across the channel, it seems that would knock down the river level several feet at a given point.
The Forum series mentioned most aquifers are so brackish the farm animals won’t drink it; that may have been in the western part of the state, though. If it is only good for irrigation, it may not be an issue to just drop the floodwater straight down. I suppose it may also depend on whether the aquifers beneath us move into other, less brackish aquifers that can be or are used for drinking and municipalities (thus a filtering, charcoal layer). Also, if the water can be directed into the bedrock, it doesn’t seem geological shifting of the soil should be an issue; the fracking going on out west would seem to cause more problems in that way. I guess I can’t help but wonder if there are millions of acre-feet worth of storage beneath us that we normally can’t access (for drainage) because of the thick goo we live on, and all the water must run off the surface. Maybe we can use that “storage space” to take the head off major floods. Then the dikes can handle the rest of it without need for a diversion or surface storage.
Since we may cause problems for folks up and downstream with a diversion – and we really need to look at their side of it – maybe there is another solution. I don’t know if this is feasible or not but people are always saying, “Think outside the box.” This seems to qualify for that standard. I should have put it out there sooner but it seemed a little too off the wall; since the discussion still seems to be going, though, maybe this is a useful solution so I’ll throw it out there.