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below the dam, where the area of the stream was fourteen feet, four independent tests were made of the velocity of the current, the distances taken and the times being different. The largest quantity of water passing at this point was 8,378 gallons per minute, the smallest, 8,064; the average of these four tests was 8,169 gallons per minute. The section taken at the dain shows more than 18 feet area, and a larger flow of water. We are of the opinion that this area was too large for the average distance that the test was made, and have therefore disregarded it.

At a quarter of a mile above the dam the area was fourteen feet; three experiments were made here to ascertain the velocity of the current, averaging from 7,949 to 8,081 gallons per minute; the mean of these experiments gives the flow of the water as 7,961 gallons per minute, or 208 gallons per minute less than the gauging below shows. This result is as close as can reasonably be expected in arriving at the flow of water in a stream that is at all irregular. We shall assume that the flow of water below the mouth of Pony creek at the time the tests were made in the creek in the early part of December, 1884, was 8,000 gallons per minute, and that of this amount not more than 2,700 gallons per minute came down the old channel of Keg Creek above that point, and this largely from Williams' millrace. We have stated before that the county ditch began near the northeast corner of section 27, township 72, range 43 west, and passed through sections 27, 28, and 33, and reached the old channel of Keg creek near the southeast corner of section 32. Starting just below Williams' dam, it made a direct course, crossing the old channel of Keg creek and re-crossing at about one-half mile below. Near the lower crossing the water in the ditch was gauged; the area of the water at the time was 66 feet, the area of the excavation not far from 300 feet, and of the space included within the embankment thrown up on each side of the ditch not less than 1,000 feet, so that in case of extreme high water most of it would pass down this direct broad channel, where the fall was reached in three miles that required seven miles in the old channel to make; whatever did pass down the old channel would naturally run slow and would deposit in its course much of the material brought from the high ground, and held in solution while the current was rapid. The area of water in the county ditch when taken was 66 feet; in the three tests the velocity was 196, 200 and 204 feet per minute. The mean of these, 200 feet, gives the amount of water passing as 98,743 gallons per minute. This gives the amount of water passing as twelve and one-third times as much as in the old channel below the mouth of Pony creek. At the lower crossing of Keg creek by the county ditch the excavation was below the old bed of the creek, so that when the Commissioners were there, water from the north or downstream side of the old creek bed was running very freely into the ditch, the bed of the old creek being three feet higher than the surface of the water in the ditch.

To understand the condition fully, it is necessary to get the relative elevations of different points with reference to each other. For the purpose of

comparison we shall use as the basis of this the top of the dam which was the cause of this complaint.

Surface of water above top of dam, feet...

Surface of water at mouth of Pony creek above top of dam,


Surface of water in Williams' race above mill above top of dam,

Bottom of mill-race above top of dam, feet...
Surface of water in Keg creek below mill, above top of dam,


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Bottom of Keg creek below mill, above top of dam, feet.
Top of wheel at mill above top of dam, feet....
Bottom of creek on wheel platform, above top of dam, fect...
Surface of water in county ditch, lower crossing, above top
of dam, feet.

Bed of old creek, south side, lower crossing, above top of dam,

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Bed of old creek, north side of lower crossing, above top of dam, feet...












The commissioners are advised that the county ditch was opened for the passage of water in about May, 1880, and the dam put in by the C., B. & Q. R. R. Co., in the fall of the same year. They are also advised that the top of the dam was two feet and five inches above the bottom of the creek when it was put in. They were also informed by residents that in the early settlement of the country the area of land between the county ditch and the old channel of Keg creek was often wet; that during periods of high water the channel was not of sufficient size to carry the water, and that at many points it overflowed the banks and remained on the lowest grounds a large portion of the time. That afterwards levees were thrown up at various points, to keep the water in the channel, and by confining the water in the channel it was washed out and materially enlarged. That since the county ditch was constructed, the channel had begun to fill up.

The Commissioners assume that the foregoing statements are true, and on this hypothesis they are convinced that more than ninety per cent of the water, at the stage when the streams were gauged, and in high water probably more, was diverted; that the earthy matter in solution in the water that went through the old channel with the slower current has deposited the alluvium all down the creek from Williams' mill to its junction with the ditch. They are also of the opinion that the dam had but little effect, as the stream has evidently filled up as much below the dam as above, and all from this deposit.

In our judgment the removal of the dam would have no effect whatever to restore the size of Keg creek to its original channel. To confine it is the only method that suggests itself to us as practicable for restoring Keg creek

to its former size. The present bed of the old creek on the north or lower side of the county ditch at its lower crossing is nearly seven feet above the top of the dam, yet this drains into the county ditch quite an amount of water from the vicinity of Williams' mill, probably leakage from his millrace; the surface of the water in the ditch at this point is 34 feet above the dam. The amount of water in Pony creek is not sufficient to force and keep a large channel open, and the floods of that creek were necessarily too large to be confined to it. Under the circumstance the Commissioners do not feel it to be their duty to order the removal of the dam, believing that it would not remedy the evil.

Des Moines, Iowa, January 20, 1884.




Filed, July 23, 1884.

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Damages caused by overflow of the Missouri River.

The parties complain that the Burlington & Missouri River Railroad in Nebraska have constructed an embankment across the Missouri river bottom, west from the town of Pacific Junction, in Mills county, Iowa, being the approach to the Plattsmouth bridge over the Missouri river. That in the construction of this embankment the company has not provided openings for the passage of water where it naturally flowed, and has entirely filled up the O'Neal slough, the Jessup slough, and other sloughs which were important water courses in time of floods in the river. That the O'Neal slough was, previous to the construction of the embankment, an arm of the Missouri river, more than one half mile in width, and carried off the surplus water during an ordinary flood, and saved hundreds of acres of tilable land from overflow. That the embankment serves as a dam, forcing the water cast away from the river, and overflows farms that were dry and free from any danger from overflow before its construction. That the embankment was constructed in the years 1880 and 1881, and has since that time backed water for miles above, and over lands four miles east of the river. That by forcing the water east and discharging it through openings from one to two miles east of its natural course, the lands of those living. south of this embankment, as well as north, have been flooded, to the great detriment of the owners and occupants; and that the loss between June 15 and July 1 to occupants of said lauds was more that $10,000.

That the company is now obstructing the channel of the Missouri river at the I'lattsmouth bridge, by throwing stone at the foot of the piers and tres

tle work of the bridge, and that there is a levee of stone running under the bridge from the end of the embankment to the water's edge, which forms a dam. That the opening under the bridge is only eight hundred feet, while eighteen hundred feet is required for the passage of the water. They ask the Commissioners to investigate the charges, with the view of having the obstructions removed wherever the embankment obstructs the natural flow of the water.

The answer of the company to the foregoing complaint is contained in a communication from Mr. T. E. Calvert, chief engineer of the company, and Mr. G. W. Irving, the engineer who made the surveys, map and profiles which accompany the answer, and which were submitted at the request of the Commissioners.

Mr. Calvert says, first: That it could not have been possible that the embankment in any way aided the overflow; that the water was two feet lower in the river than it was above the grades, which would have been impossible on the theory that the water was backed up from the embankment. Second: the fall from where the water flowed over the bank out of the river was much more than the average fall of the Missouri river, and more than the fall below the embankment, it being above, 1.79 feet per mile; below, .97 feet per mile, or nearly double. Third: from profiles and levels taken, it appears the result would have been practically the same had the embankment been removed, for the water which came out of the river could never have been carried down O'Neal slough without running over the high ridge east of the slough and flooding the low ground east.

If we assume that our grade did back up the water we find that by extending the plane at which water stood during extreme high water between the point north where it came out of the river and the embankment, it run so close to the ground south of the embankment that it could not have been carried off, so the back water was about the same with the embankment as it would have been without. If we assume that the grade backed the water up, then this plane spoken of would have been at a still greater angle with a horizontal plane, and would have intersected the surface south of the embankment still sooner.

Mr. Irving says: The cause of the overflow is undoubtedly the cutting away of the high banks along the river, marked on the map B, A, C, between a mile and a half and two miles above the bridge. The greater part of this cutting has occurred within the past two years; these overflows will continue until the cutting stops, and will be greater every year for the same stage of water. The overflow this year was much greater than the year before, yet the gauge readings show equally high water both years. The shape of the bank has a tendency to raise the water, for it receives the current nearly at right angles. From the survey of the Missouri river, made in accordance with an act of Congress, by Major Charles R. Suter, of the engineer corps of the United States army, the fall of the Missouri river is given at low water, November 10, 1878, from Omaha to Plattsmouth, as .75 of a foot per mile; from Plattsmouth to Nebraska City, 1.99 feet per mile. Dur

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ing high water, June 30, 1879, the fall from Omaha to Plattsmouth was .79 of a foot per mile; from Plattsmouth to Nebraska City, 1.11 of a foot per mile. On December 3, 1884, the fall from one mile above the bridge to the bridge was 1.04 feet; from that point to A on the map, 7,795 feet, was 2.63 feet, or 1.79 feet per mile; the fall below the bridge for one mile was .75 feet.. Had the bridge retarded the flow of water the fall would have been less instead of greater above the bridge. He is not entirely sure of the fall last spring, but from back water in the slough and drift he thinks it checks this.

The ground slopes from the river to the bluffs, and if the water gets over the banks it will flow towards the east, unless intercepted by sloughs, which carry it south. The profile B, A, C, No. 4, shows the cross section where the river came over the bank, and has a cross section of 5,300 square feet, 1,800 feet of this was south of A, or near where the O'Neal slough comes from the river. This was a greater area than the O'Neal slough, and with the velocity acquired from the river could not have been carried had the slough been unobstructed. This leaves 3,500 square feet north of "A" to be taken care of. The slough running to the iron bridge has an area of 1,280 feet, and the two sloughs running directly east, 780 feet. Had there been no water from the river south of the section line, the county bridge and the country west of it could only have passed 900 square feet before overflowing lands to the east, filling the low places near Keg creek. This water passed through iron bridge No. 5 and Keg creek bridge. The level at Dashner's was higher than at the south side of the iron bridge.

On the first of July the water was flowing through the O'Neal slough to the borrow pit, and at the junction there was a fall of about four inches, the borrow pit not being full. At this time the water was flowing over the banks near Haney's house, and down the slough to the little iron bridge; it was also flowing down Jessup's slough and through the low ground to the iron bridge. He gives the area of the water at the iron bridge as 3,870 feet; at bridge No. 5, as 3,080 feet, and the two bridges at Keg creek as 1,072 feet. The elevation of the ground where the water leaves the river is from 512 to to 513 feet above his base; at the iron bridge, 507; at bridge No. 5, 507; at Keg creek, from 507 to 508; or, the ground at these points is from seven to eight feet lower. The bottom of the O'Neal and Jessup sloughs, at their lowest point north of the railroad embankment, is shown to us by the profile to be about the same level, from seven to eight feet below the ground where the river comes out, a little more than a mile above. It is claimed by Mr. Irving that the shore line opposite the mouth of the Platte river has cut away more than one third of a mile between the years 1879 and 1884, and that the banks at that point were formerly very much higher than the high water of 1883 and 1884; and that until some method has been adopted to stop the overflow the water will run from this place to the lower grounds east, irrespective of any construction made by the company.

Mr. Morrison, the engineer who located and constructed the Plattsmouth bridge, says in his report, which we here quote as the company's answer to

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