Court Opinion

ID: 9628525
Source: CourtListenerOpinion
Date Created: 2023-08-22 09:23:37.622464+00
Date Added: 2024-06-11T09:09:13.823540
License: Public Domain

SWANSTROM, Judge,
dissenting.
I do not agree that the jury verdicts in this case were supported by substantial evidence. Therefore, I dissent.
The following are undisputed facts which the jury could not ignore. During the time when the canal bank failed, the Salmon River was at a record flow and water from the river was pouring over the top and side of the headgate structure into the canal. The height of this water above the structure was at least fifteen inches, according to plaintiffs’ own witnesses. The break occurred in a low spot in the canal bank, about 5,000 feet down from the headgate. The trash rack maintained by the state was another 4,500 feet below the break point.
The circumstantial evidence most favorable to the canal company was that, due to partial clogging of the trash rack from debris and due also to the excessive amount of water coming into the canal, the water level at the trash rack rose twenty-one inches, from its normal depth of 3.6 feet to a depth of 5.3 feet. It is important to remember that 5.3 feet was the maximum height of the water at the trash rack, according to the plaintiffs’ evidence. According to evidence offered by defendant, it could not have reached that depth, but for purposes of this discussion I will assume it did.
Because of the slight downward slope of the canal the relative elevation of the canal floor at the break point was approximately four feet higher than the relative elevation of the canal floor at the trash rack. In other words, the average drop in the canal between the break point and the trash rack was about one foot in each 1,000 feet. The normal depth of the water at the trash rack was 3.6 feet, as noted above, while the normal depth at the point of the break was approximately 2.7 feet. In terms of relative elevation, the surface of the water at the point of the break was about 3.1 feet higher than at the trash rack. Therefore, if the water surface did rise a maximum of 1.7 feet, to 5.3 feet at the trash rack, the relative elevation of the surface of the water at the trash rack was still more than one foot lower than the normal relative elevation of the water surface where the break occurred. The actual difference, of course, was even greater than that because the surface of the water at the break point was above normal due to the Salmon River flooding into the upper end of the canal.
The critical question thus becomes: If clogging contributed to the rising of the water surface at the trash rack to 5.3 feet, *346how could that affect the water surface some 4,500 feet back up the canal when the surface there was already at a higher relative elevation? Plaintiffs attempted to show how this could have happened through the testimony of Dr. Watters, an expert on open channel hydraulics. He explained that, in a flowing open channel with a constant inflow, an obstruction at the downstream end, which diminishes the outflow, would create a “backwater curve”— in simple terms, a slowing of the stream with a resultant increase in depth of the flowing water in back of the obstruction for some distance. The amount of increase in depth is smaller as you go further back up the channel from the obstruction until it reaches a point at which the obstruction has no effect on the depth of the water. He explained that the increased depth of water, if any, at a given point in the open channel can be calculated using a complicated formula. The formula requires “plugging in” several “known” factors, such as the size, shape and slope of the canal, as well as the rate of flow of water into the canal and the depth of the water at the point of obstruction. The presence and effect of this backwater curve was crucial to plaintiffs ease and was totally dependent upon Dr. Watters’ testimony.
Dr. Watters based his testimony on both his own personal observations and the reports of others. Dr. Watters first visited the site four years after the washout. He inspected the canal and then made his calculations, using his own measurements and observations as to the size, shape, roughness and slope of the canal. He also relied upon some surveying data furnished by the state’s expert and another engineer. However, in making his calculations he was forced to “assume” two of the required factors. He assumed that the water depth at the trash rack had reached 5.3 feet before the washout occurred. He also made certain assumptions as to the rate of flow, although he admitted he did not know what the flow actually was when the washout occurred and no other witness provided this information. Dr. Watters further testified that for the purpose of his calculations the rate of flow in the canal and the depth of water at the trash rack were “two critical pieces of information.” He then estimated that if clogging had occurred as plaintiffs’ contended, and if the flow rate was 175 cfs, it could have caused an increase in the depth of water at the place where the break occurred of from two to three inches. Dr. Watters, however, did not purport to say how deep the water was, without the backwater curve effect, at the point in the canal where the break occurred. The majority nevertheless says that this three-inch increase in water depth “represented a significant fraction (twenty percent) of the fifteen inches — over the normal water level in the canal — necessary to reach the top of the banks.” At the place where the canal broke it would take forty-eight inches of water to fill the canal. Giving the canal company the benefit of all inferences, the state can only be held responsible for, at most, three inches of water depth out of a total water depth of at least forty-eight inches — an insignificant six percent.
Furthermore, Dr. Watters did not testify that clogging was the probable cause of the canal washout. On the contrary, he said:
I guess we really don’t know just exactly how high the water had to get. I suppose it’s possible that the trash rack clogging was just enough to precipitate the failure. A speculation, certainly, but something to consider.
In an earlier written report, introduced into evidence, Dr. Watters had stated that
it seems more justifiable to claim that the washout was caused primarily by high discharges,1 rather than trash rack clogging. The trash in the canal undoubtedly aggravated the situation, but should more appropriately be used as evidence of substantial overtopping of the canal headworks and a resulting ex*347cessive flow entering the canal. [Emphasis original.]
There was, in fact, substantial evidence that the excessive flow from the Salmon River into the canal alone could have over-topped and washed out the canal bank. Moreover, Dr. Watters was asked by plaintiffs’ counsel if he thought the canal could have washed out even without the water actually overtopping the bank. Dr. Watters responded:
A. Oh. I think it’s a possibility and one of the basis of the opinion is that the material in the area as I observed it during my visit was a very sandy, gravely type of material which I wouldn’t advise using for canal banks but in any case when the water gets close to the top it will begin, and the bank gets narrower, then there will be more of a tendency for the flow to seep through the gravelly mixture and as the flow begins to move through the mixture it tends to washout grains and sand and create larger openings and sort of like if you build a basin or container out of sand and fill it up towards the top, as the water gets towards the top it begins to washout and eventually will washout a piece and as that piece washes out the whole thing comes apart. I think there’s a possibility that could have been a contributing factor.
In making his calculations, Dr. Watters assumed a water depth of 5.3 feet at the trash rack due to clogging. However, he had not been informed that the tops of the gates in the bypass channel were only 4.3 feet high, relative elevation. He was therefore unaware that, before the water could reach 5.3 feet, it would flow over the bypass gates, through a twenty-four foot opening, and into the bypass channel. This is true even if the float-actuated gates remained shut. The majority lightly dismisses the importance of this undisputed evidence by saying “[t]he fact that some water would have escaped into the bypass channel was not fatal to the expert’s analysis.” Dr. Watters testified, however, that the depth of water at the trash rack was a “critical” piece of information for the purpose of his calculations. The evidence clearly showed it was highly improbable that the water depth could reach 5.3 feet because of the escapement structure the state had provided at the trash rack. ■
Finally, as to the effect of the debris itself, the evidence showed that it would raise the water level at the trash rack at most a few inches. Giving full credit to Dr. Watters’ testimony about a backwater curve, the debris also would have produced only a minute rise in the water level where the canal broke — if it had any calculable effect at all.'' The escapement provided over the tops of bypass gates would further reduce, if not completely eliminate, the effect of the clogging if the water level in the canal rose above 4.3 feet at the trash rack. These considerations and a thorough review of the record leave me strongly convinced that there is a lack of substantial evidence to support the jury’s verdicts in this case despite the “permissible inferences” the jury could have drawn. I would reverse the judgments.

. In using the term “high discharges” Dr. Watters was referring to the excessive water flowing from the Salmon River over the top of the headgate structure into the canal.