REPORT OF MR. WILLIAM P. SMITH, ASSISTANT ENGINEER. UNITED STATES ENGINEER OFFICE, SIR: I have the honor to submit the following report made on improvements on the San Joaquin River, including Stockton and Mormon sloughs, during the present fiscal year, and with which I was connected as assistant engineer. UPPER SAN JOAQUIN RIVER. On what is known as the Upper San Joaquin, which is that portion above the city of Stockton, no improvements have been made during the year. Two examinations were made by yourself-one of Paradise Crevasse, 2 miles above the railroad bridge on September 30, and one in the vicinity of the town of Grayson October 3. LOWER SAN JOAQUIN RIVER. The city of Stockton is situated on a slough of the same name 24 miles from its entrance into the San Joaquin River. For about 4 miles from this junction downstream it is termed the "Narrows." In this portion of the river the two improvements were made. The new channel or cut-off through what is known as the Devil's Elbow, commenced during the last year, was completed, and a shallow reach above it was dredged. CUT OFF AT DEVIL'S ELBOW. The contract for making this new channel of the river was let in August, 1883. The contractor, after about half completing it or after excavating to about half the required depth, encountered a stiff clay, which his machine was unable to dredge. Several extensions of time were given him, but the contract was finally taken from him on May 15, 1884, and on July 21, 1885, was relet to Thomas H. Williams, jr., at 15 cents per cubic yard. The first contract was for 16 cents per cubic yard, and the contractor excavated 23,594 cubic yards. He was paid for 23,146 cubic yards, less 10 per cent. Work was commenced on the new contract August 10, 1884, and the cut completed October, 1-84. The amount of material taken out 24,519 cubic yards. A levee was built on the inside of the cut with the dredged material. The new channel was made 100 feet wide at the bottom, and the sides left as formed by the dredge makes the width at low-water level 124 feet. It is 10 feet deep at low water and the length on the center line is 900 feet. The cut was obstructed for a time near the lower approach by the dredge belonging to the first contractor sinking near the left bank. It was removed by the United States snag-boat Seizer in December. The Devel's Elbow was considered the worst bend on the lower river. The old channel is fast filling up, and the new one is used by all, and fully appreciated by both steamers and sailing vessels. DREDGING IN THE NARROWS. Above the Devil's Elbow, and a short distance below Stockton Slough, we find each year a deposit of clean white sand, which is brought down the San Joaquin River during high water. The shoal is generally about 2,000 feet in length, and at low water and low tide there was less than 5 feet of water before dredging was commenced. This same The rise and fall of the tide is about 2 feet during the low water season. reach of the river was dredged once before. The portion dredged this year was 1,050 feet in length, 60 feet wide at the bottom, and to a depth of 9 feet at low water. Thirteen thousand one hundred and twenty-two cubic yards of sand was dredged and deposited on the bank. The cut began filling at once with the sand that is constantly moving down the river, but no further trouble was experienced during the season. It is probable, however, that next year shoal water will be found at the same place. At the outlet of Stockton Slough on its turn into the Narrows a bar had formed of a mixture of sand coming down the river and earthy sediment coming down the slough. This was taken out, necessitating dredging a channel 700 feet long an average width of 80 feet and to 9 feet at low water. The amount of material taken out at this place was 12,908 cubic yards. This cut has maintained its width and depth the last I heard from it, and had saved the steamers much annoyance and delay in making the turn in and out of the river. STOCKTON SLOUGH. That portion of this slough between the outlet of Mormon Slough and the river, a distance of about 7,000, feet is filled up each year by the sediment coming down Mor mon Slough to an extent that makes navigation very troublesome, and compels vessels to often wait for the 2 feet rise in the tide. About the same depth of water was found here this year before dredging as existed in the Narrows, but the slough being wide, with sloping banks on both sides, it is more difficult to keep the channel narrow at its best. Five thousand two hundred and fifty feet in length was dredged to 9 feet at low water; 2,950 feet had a width of 60 feet, and 2,300 feet a width of 110 feet. Amount of material dredged and put ashore was 60,786 cubic yards. MORMON SLOUGHI. This slough, which is navigable at high water about 10,000 feet from its month, had at low water of this season a practicable chanuel of less than 3 feet in depth. The lower half had in places over 4 feet, but the upper portion less than 2 feet. It was not practicable with the funds available to dredge the entire length. The dredge that was used drew 4 feet. Nothing was done when it would floa freely at low tide. When the channel was dredged it was made 60 feet wide and 6 feet deep at low water. Four thousand two hundred and fifty feet in length was excavated to these dimensions, requiring the dredging of 47,595 cubic yards of soft sediment and sand. In the Narrows in Stockton and Mormon sloughs the work was done by the Von Schmidt pump-dredge, and the material carried in some cases 2,000 feet. The channel was made of very uniform dimensions, and the material distributed on shore in such a manner as to leave no possibility of its return to the channel. Less than ten years ago 69 cents per yard was paid for this class of work. The contract was let this year for 17.49 cents per cubic yard. Two years ago the United States constructed a restraining barrier on Mormon Slough, about 200 feet above the head of navigation. It was understood that the city authorities would excavate each year the material collected by it. The city also built a similar and smaller one some 2,000 feet above. There has collected behind these two barriers, in two years, over 200,000 cubic yards of sediment, much of which would have been carried into the channels of Mormon and Stockton sloughs below. A small portion of this has been removed each summer by teams, but it is so little that it gives poor encouragement to raise them or construct others. The barriers have done their work, and are, of course, now useless. It is suggested that a portion of the next appropriation for Mormon Slough be expended in clearing out behind the lower barrier. Three sheets accompany this report showing the area dredged over, and the condition before and after dredging of the narrows of Stockton Slough and Mormon Slongh. Respectfully submitted. Capt. A. H. PAYSON, WM. P. SMITH, Assistant Engineer. Corps of Engineers, U. S. A. Estimate of exports and imports of the city of Stockton for the year ending June 30, 1885. Estimate of trade by steamers and barges upon the Upper San Joaquin for the year ending Tons. 150,000 40,000 1500 4,000 50,000 283, 600 June 30, 1855. An appropriation of $8,500 was made by the act of July 5, 1884. The report of an examination by Lieut. S. W. Roessler, in October, 1881, with recommendations for the expenditure of this money, is herewith. The Mokelumne is only navigable in its tidal part, which extends some 22 miles above the point where it empties in the San Joaquin River. Of this distance rather more than half has suflicient water and offers no obstruction, save that arising from the narrowness of the stream itself; the remainder has still enough water, but is obstructed with snags, while the heavy growth on the banks is a cause of much damage to passing boats, taking, as these do, the entire width of the river. The snag boat accordingly received orders in November to clear a practicable and reasonably safe channel from Snodgrass Slough, where the obstructions began, to Benson's Ferry, the head of navigation, a distance of about 10 miles. These instructions were carried out between November 1 and December 8, 1884, by the removal of 160 snags and 314 overhanging trees. The concave banks were also partially cleared. Though now navig able, by the steamers used, to Benson's Ferry, a good deal of snagging and clearing could still be done with advantage, and to these purposes it is proposed to devote the funds available and asked for. Total amount appropriated. $8,500 00 4,958 09 Money statement. Amount appropriated by act approved July 5, 1884. July 1, 1885, amount available Amount that can be profitably expended in fiscal year ending June 30, 1837 Submitted in compliance with requirements of section 2 of river and harbor acts of 1866 and 1867. $8,500 00 4,958 09 3,541 91 5,000 00 REPORT OF LIEUTENANT S. W. ROESSLER, CORPS OF ENGINEERS. SAN FRANCISCO, CAL., October 21, 1884. SIR: I have the honor to report the results of my examination of the Mokelumne River, made by your verbal instructions, October 18. The Mokelumne empties into the San Joaquin 20 miles above the latter's junction with the Sacramento, and for a distance of 22 miles above its mouth is a tidal stream with a narrow and crooked channel but ample depth of water. At a point 15 miles above the mouth the river divides into two branches, the North and South Forks, which join 9 miles below, forming Staten Island. The North Fork is the channel. New Hope Landing, situated at the head of the island, is the present head of low-water steamboat navigation. The steamboat Constance, of the California Transportation Company, of 265 tons capacity and 5 feet draught, plies between this point and San Francisco from once to thrice weekly throughout the year. It is the principal landing of the boat, and furnishes an outlet for a large section of country to the southeast. From the mouth to Snodgrass Slough, which empties into the North Fork 14 miles below New Hope Landing, the river's course lies through tulle lands and offers no obstructions to navigation except those presented by the narrowness and crookedness of the channel. From Snodgrass to New Hope the banks are wooded, and snags and overhanging trees form the obstructions; a sand-bar across the fork at its upper end, giving 3 feet at low tide, obliges the steamboat to make the landing at medium or high stages of the tide, which here has a range of 44 feet. No complaints were made that this bar formed an obstruction, as the steamboat can easily regulate its movements below so as to reach this point at a favorable time. The next landing is Benson's Ferry, 7 miles above New Hope Landing. The present trade to Benson's is carried on by small sloops and schooners, and consists principally in the transportation of bricks from a large brick-yard located just above the ferry. But little grain goes down from this point. The steamboat has occasionally gone this far at very high water, but only when strongly pressed to do so, owing to the injuries the boat has to sustain by striking against projecting trees and branches. The opening of steamboat navigation to Benson's would supply cheap transportation to a large section of country to the northward, whose outlet is now by rail. The reach between New Hope and Benson's is from 70 to 80 feet wide between banks, which are covered by trees and a dense growth of brush-wood, principally alder. Overhanging trees and snags form the obstructions. I found at no point a less depth than 6 feet at low tide, except at the ferry, where the depth was 4 feet. The tidal range here is about 24 feet, and vessels drawing 5 feet can make the landing close to the brickyard. Beyond Benson's the tide rapidly decreases in height, and the river becomes narrower, shoaler, and more crooked, making navigation impossible. To make the river navigable between New Hope Landing and Benson's Ferry there will have to be removed in the neighborhood of seventy-five trees and sixty-five snags and the banks be cleared of brush-wood where the steamboats would rub in making the bends, in all about 7 miles of brush-wood. It is recommended that the snag-boat commence work in the North Fork opposite Snodgrass Slough, removing overhanging trees and snags, and clearing the banks of brush-wood as far up as Benson's Ferry. The work will be slow, owing to the narrowness of the channel and the consequent necessity of using a landing-tackle to haul the snags and trees well up on the banks, where the boats cannot touch them as they rub along the bank. The trees which spring from the edge of the bank should be dug up with their roots so as to leave no stump against which the boat might strike. Owing to the slackness of the current the snags do not show themselves by any ripple on the surface, and the water is too muddy to enable one to see them. Mr. Hansen, at New Hope, is familiar with their location, and it is suggested, to avoid loss of time hunting for them, that the engineer in charge of the snag-boat be authorized to employ him for a day to go over the reach and point out where they are. There is no fuel to be had along the river, and it will be necessary for the snag-boat to bring her barge. The barge can be left at the mouth of Georgiana Slough. The South Fork of the Mokelumne affords a good channel to within a mile of its head. The upper end for the distance of 1 mile is full of snags, very narrow, and very crooked. The width in places does not exceed 60 feet. It was suggested to clear it of snags so as to enable the boats to approach New Hope Landing and depart by either branch. The width, however, is not believed to be sufficient to make this branch at all practicable at its upper end. No work is therefore suggested for this point. Capt. A. H. PAYSON, Corps of Engineers. S. W. ROESSLER, First Lieutenant of Engineers. Besides the above, some 2,000 tons of grain and a large quantity of brick and lumber were carried in sailing vessels. RR 4. IMPROVEMENT OF SACRAMENTO AND FEATHER RIVERS, CALIFORNIA. Reference is made to the accompanying report of Mr. A. Boschke for details of the snag-boat's operation during the year. The Seizer was in commission on the Sacramento and Feather rivers one hundred and forty-eight days, of which ninety-nine days were on the former stream. Seven hundred and sixty-four snags and 41 trees were removed on the Sacramento. Five days were spent in scraping Fremont Bend and Salmon Bend, and thirteen days in the extension and strengthening of the existing dams at Parrott's Chute and Call's Bend. At my request the railroad company removed the superstructure of the unused bridge at Knight's Landing, and its pier, which had formed a bad obstruction, was removed by the snag boat. On the Feather River 302 snags and 298 trees were removed and destroyed, and fifteen days were spent in building temporary dams to assist in the formation of a low-water channel. The assistant engineer in charge reports a significant change in the character of the bars in the Feather River, on which the presence this year for the first time of sand and gravel indicates the progressive influence of the débris from the hy draulic mines. During the winter's suspension of work the snag-boat was taken out of the water at Stockton for repairs. Every bit of bad timber was replaced by new, the hull received additional strength, the machinery, boiler, &c., were overhauled, repaired, and improved, and the boat went into commission in as good, if not better, order than when new. During the season barges on the Sacramento were loaded as follows: |