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4. The district engineer proposes levee and channel improvements in the lower 13 miles of the river, modification of two division dams, revision of bridge and road facilities, and provision of necessary protective works at bridge abutements and piers within the limits of improvement. The improvements are designed to protect the adjacent areas from a flood of 1,500 cubic feet per second and are estimated to cost $98,600. The total annual cost is estimated at $5,825 and tangible annual benefits at $17,000. In view of the favorable ratio of benefits to costs of 2.9 to 1, the district engineer concludes that the improvement is economically justified and recommends its construction subject to certain conditions of local cooperation. The division engineer concurs.

5. The Board of Engineers for Rivers and Harbors is of the opinion that the improvement recommended by the reporting officers will provide adequate protection from future floods and is economically justified. Accordingly, the Board concurs in the recommendations of the district and division engineers.

6. After due consideration of these reports, I concur in the views of the Board. The proposed improvements will provide adequate protection for approximately 2,250 acres of improved land along the lower 13-mile section of the river and are clearly justified by the prospective benefits. I therefore recommend the improvement of Spanish Fork River, Utah, substantially as outlined in the report of the district engineer and as shown on the accompanying drawing with such modifications thereof as in the discretion of the Secretary of War and the Chief of Engineers may be advisable, at an estimated cost to the United States of $74,500 for construction; subject to the conditions that local interests furnish assurances satisfactry to the Secretary of War that they will: (a) Provide without cost to the United States all lands, easements, and rightsof-way necessary for construction of the works and bear the expense of all necessary alterations of roads bridges, utilities, and irrigation works; (b) hold and save the United States free from damages due to the construction works; and (c) maintain and operate all the works after completion in accordance with regulations prescribed by the Secretary of War.

R. A. WHEELER,
Lieutenant General,

Chief of Engineers.

DEPARTMENT OF THE INTERIOR,

Washington 25, D. C., October 19, 1945. Lt. Gen. RAYMOND A. WHEELER,

Chief of Engineers, War Department. MY DEAR GENERAL WHEELER : By letter dated July 24, 1945, General Reybold transmitted to me for my information and comment a copy of his proposed interim report on a preliminary examination and survey of “Streams draining into Great Salt Lake, and the Great Basin, Utah and Nevada” covering Spanish Fork River, Utah, together with the reports of the Board of Engineers for Rivers and Harbors and of the division and district engineers. In accordance with provisions of section 1 of the Flood Control Act of 1944, General Reybold asked for my views on the report by October 30, 1945.

The report recommends improvements along the lower 13 miles of the Spanish Fork River by building levees, rectifying the channel, and revising and modifying existing diversion dams, bridges, and road facilities.

When the report was prepared this Department had no plans regarding irrigation or power development on the Spanish Fork River or its tributaries. In the past 4 months, however, the Bureau of Reclamation has been investigating the possibilities of making a large diversion from the Colorado River Basin into the Bonneville Basin by way of Diamond Fork and Spanish Fork Rivers. Although the studies are far from complete, the project looks promising.

At present water is carried through a tunnel from Strawberry Reservoir into Diamond Creek, a tributary of the Spanish Fork River. The contemplated project is to include a 60,000-acre-foot reservoir at Monks Hollow site, a 25,000-acrefoot reservoir at the Little Diamond Creek site, both on Diamond Creek, and a diversion aqueduct from Spanish Fork River into the existing Sevier Bridge Reservoir on Sevier River.

Should a flood occur, even though the reservoirs are full, up to 700 second-feet could be diverted into Sevier Bridge Reservoir by closing the tunnel diversion from Strawberry Reservoir. Another 500 second-feet could be diverted by irrigation diversions above the flood area. Such diversions would handle all but a

minor part of the record peak flow of 1,430 second-feet as mentioned in paragraph 19 of the report.

This Department's proposed project, if approved, probably would not enter the construction stage for several years, but if such project were constructed prior to or during construction of your proposed improvements, you might wish to adjust your plan accordingly.

Your proposed plan of improvement will be beneficial to a large portion of the Strawberry Valley project. The plans are satisfactory to this Department. However, since that portion of the Spanish Fork River to be improved under your plan traverses the Strawberry project, thereby possibly affecting project lands and facilities with a possible reduction in irrigable area, I would like to have the opportunity of making a further review of your proposal when final plans are prepared. Sincerely yours,

MICHAEL W. STRAUS, Acting Secretary of the Interior.

MARCH 22, 1946. The SPEAKER OF THE HOUSE OF REPRESENTATIVES.

DEAR MR. SPEAKER: I am transmitting herewith an interim report date February 1, 1946, from the Chief of Engineers, United States Army, together with accompanying papers and an illustration, on a preliminary examination and survey of “Streams draining into the Great Salt Lake and Great Basin, Utah and Nevada," covering flood control on the Spanish Fork River, Utah. This investigation was authorized by the Flood Control Act approved on June 28, 1938.

In accordance with section 1 of Public Law 534, Seventy-eighth Congress, copies of the proposed report of the Chief of Engineers were furnished the Governor of the State of Utah and the Secretary of the Interior. While the State of Utah acknowledged receipt of the copy of the report on July 31, 1945, no written views or recommendations with respect thereto have been received. The views of the Department of the Interior with the reply thereto are inclosed.

The Bureau of the Budget advises that there is no objection to the submission of this report. · Sincerely yours,

ROBERT P. PATTERSON,

Secretary of War.

JORDAN RIVER, UTAH, AND LITTLE VALLEY WASH AT MAGNA, UTAH The CHAIRMAN. The next project under consideration is the report on the Jordan River at Salt Lake City, Utah, and Little Valley Wash, at Magna, Utah.

As I understand, Colonel Herb, that report is before the Budget? Colonel HERB. Yes, sir.

The CHAIRMAN. Will you give us the location and the general watershed of the Jordan River, and the problem involved, and the proposed solution of it here in the Salt Lake City area? STATEMENT OF COL. E. G. HERB, ASSISTANT DIRECTOR, CIVIL

WORKS DIVISION, OFFICE, CHIEF OF ENGINEERS Colonel HERB. The authority for this report is contained in the Flood Control Act approved June 28, 1938.

The Jordan River has a drainage area of 3,295 square miles, with its source in Utah Lake, from which it flows northward through a mountain gap known as the Narrows, and thence across the central part of Jordan Valley to Great Salt Lake Jordan Valley is a rectangular area of about 790 square miles, of which 413 square miles are valley lands and the remainder foothills and mountains. It is surrounded by mountains except on the northwest where the flat lower

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lands border Great Salt Lake. About 15 miles south of Great Salt Lake, the Jordan River flows through the westerly section of Salt Lake City. A considerable part of Jordan Valley, to the west of Salt Lake City, drains directly into Great Salt Lake through small streams.

Magna, Utah, is located in that area on the debris cone where Little Valley Wash, with drainage area of 6 square miles, debouches from the mountains. The flows of Little Valley Wash are intermittent and no well-defined natural channel exists to carry them across the debris cone. Salt Lake City had a population of about 150,000 in 1940, and Salt Lake County about 212,000. Magna is an unincorporated mining and residential community with about 3,500 residents. Agriculture, transportation, mining, smelting, manufacturing, and the administration of governmental functions are the principal occupations in Jordan Valley. In general, the land along Great Salt Lake is inadequately drained and is used chiefly for grazing although some tracts are irrigated. Water for irrigation in Jordan Valley is obtained from Utah Lake via Jordan River, from the smaller streams which rise in the mountains and from wells.

The average annual rainfall in the lower part of the valley is between 15 and 16 inches, the benchlands average 21 inches and in the mountains the range is from 22 to 43 inches.

The CAIHRMAN. Describe the flood problem.

Colonel HERB. The records of floods for Jordan River through Salt Lake City and Little Valley Wash at Magna, Utah, consist almost exclusively of newspaper accounts, testimonies of old residents, and information from private sources. All available information concerning Little Valley Wash indicates that floods considerably larger than any of record should be anticipated. Newspaper files indicate that the largest flood in the history of the basin occurred in 1862 when the river remained in flood stage for over a month and much of the lower valley through what is now part of Salt Lake City was under water. Other floods of record occurred in 1850, 1876, 1884, and 1885. The largest flood of recent years in the Jordan River occurred in 1917. During this flood the recorded maximum 24-hour mean discharge at the gaging station near the Narrows was 522 cubic feet per second. The second largest flood of recent years occurred in 1922 when the discharge from Utah Lake was 1,370 cubic feet per second. Minor floods occur almost annually.

Future average annual direct and indirect flood damages at Salt Lake City from floods up to the largest to be expected with an average frequency of once in 100 years are estimated at $37,000. Floods of Little Valley Wash and other streams in the Magna area are usually caused by local summer storms of the cloudburst type, which are of short duration but may be extremely violent. Since 1922, seven floods have been reported on Little Valley Wash, those of 1922 and 1930 having been the most severe. Medium-sized floods occurred in 1932 and 1936, and smaller floods occurred in 1934, 1935, and 1937. Major floods at Magna may be expected with an average frequency of once in 10 years, and a peak discharge of 3,900 cubic feet per second in 100 years. The average annual flood damages are estimated at $9,310.

The plan of improvement provides for the improvement of Jordan River, Utah, at Salt Lake City, by enlargement, straightening, and removal of obstructive works from its channel, to obtain capacities

ranging from 500 cubic feet per second immediately downstream from Surplus Canal to 1,000 cubic feet per second below North Temple Street, and diverting all flows in excess of that amount to the west of the city via Surplus Canal and over the flood lands to the left of the canal into Great Salt Lake, levee construction and provision of control works just below the Surplus Canal, and enlargement of Surplus Canal to a capacity of 1,500 cubic feet per second, extension, and removal of obstructions, provision of a control structure at its head, levee construction along its northeast bank, and railroad-bridge extensions and construction at an estimated cost to the United States of $112,000; improvement of Little Valley Wash at Magna, Utah, provides for intercepting all flood flows at the mouth of the canyon above the town and · conveying them through a new channel 5,800 feet long with a levee along its east side bordering Magna and other appurtenant works at an estimated cost to the United States of $222,000.

The estimated total first cost of these projects is $818,200, of which $184,200 is the estimated cost to be borne by local interests.

The CHAIRMAN. What is the population of Salt Lake, according to your report?

Colonel HERB. About 150,000 in 1940, sir.
Mr. ROBINSON. I think it is about 190,000 now.

Colonel HERB. For the Jordan River project the ratio of costs to benefits is 1.0 to 1.5; for the Little Valley Wash, 1.0 to 1.0.

In a letter from the Department of the Interior dated February 20, 1946, the Acting Secretary of the Interior stated that the proposed works would not conflict with any existing or proposed water-conservation projects and that the proposed improvements appear highly desirable. Also, the Governor of Utah, by telegram to the Chief of Engineers dated March 15, 1946, officially endorsed and approved the proposed improvements on Jordan River at Salt Lake City and the Little Valley Wash at Magna, Utah.

(The report of the Chief of Engineers, together with the comments of the Governor of Utah and of the Department of the Interior, are as follows:)

WAR DEPARTMENT,
OFFICE OF THE CHIEF OF ENGINEERS,

Washington, March 18, 1946. Subject: Jordan River at Salt Lake City, Utah, and Little Valley Wash at

Magna, Utah.
To: The Secretary of War.

1. I submit for transmission to Congress my interim report with accompany. ing papers and illustrations on preliminary examination and survey of Jordan River at Salt Lake City, Utah, and Little Valley Wash at Magna, Utah, in accordance with the Flood Control Act approved June 28, 1938, which authorizes preliminary examinations and surveys of “Streams draining into the Great Salt Lake and the Great Basin, Utah and Nevada.” A final report on Jordan River will be submitted at a later date. Separate reports are being made on other streams covered by the authorization.

2. Jordan River has its source in Utah Lake, north central Utah, flows northward through a mountain gap known as the Narrows for 9 miles and thence continues north for 51 miles across the central part of Jordan Valley to Great Salt Lake. It drains 2,680 square miles tributary to Utah Lake and 615 square miles of Jordan Valley and adjacent mountains, a total of 3,295 square miles. Jordan Valley is a rectangular area of about 790 square miles of which 413 square miles are valley lands and the remainder foothills and mountains. It is surrounded by mountains except on the northwest where the flat lower lands border Great Salt Lake. About 15 miles south of Great Salt Lake, Jordan River flows through the westerly section of Salt Lake City. A considerable part of Jordan Valley, to the west of Salt Lake City, drains directly into Great Salt Lake through small streams. Magna, Utah, is located in that area on the debris cone formed where Little Valley Wash, with drainage area of 6 square miles, debouches from the mountains. The flows of Little Valley Wash are intermittent and no well-defined natural channel exists to carry them across the debris cone.

3. Salt Lake City had a population of about 150,000 in 1940 and Salt Lake County about 212,000. War activities have resulted in a considerable increase in the population of the general region since 1940. Magna is an unincorporated mining and residential community with about 3,500 residents. Agriculture, transportation, mining, smelting, manufacturing, and the administration of Governmental functions are the principal occuptions in Jordan Valley. The more productive agricultural lands are located to the east of Jordan River and in the southern and southwestern parts of the valley. In general, the land along Great Salt Lake is inadequately drained and is used chiefly for grazing although some tracts are irrigated. Water for irrigation in Jordan Valley is obtained from Utah Lake via Jordan River, from the smaller streams which rise in the mountains and from wells. Several railroads, air lines, and a network of improved highways serve the area.

4. Jordan River within Salt Lake City is crossed by 21 bridges, 3 fumes, and 3 siphons and receives the discharge from 5 storm sewers. Five small flashboardtype dams are located in this section of the river. Three are used for irrigation diversions, one to create a cooling water pond for the Utah Power & Light Co., and the fifth, located where the river enters the city, was constructed to divert water into Surplus Canal but in its present inadequately maintained condition it is ineffective except when flows are low. Surplus Canal was constructed by local interests as a flood-control measure about 1885 and enlarged in 1917. It extends northwesterly for about 7 miles, diverts floodwaters past the city to the low marsh area bordering Great Salt Lake and also carries water for irrigation. It is crossed by 10 bridges, 4 flumes and a siphon and has a control dam at its head which is in poor condition and effective only for controlling low flows. Near its midpoint, the canal contains the North Point Consolidated Dam which provides for the diversion of water to irrigate farm lands northwest of Salt Lake City. At Magna local interests have constructed a concrete-lined channel, about 8.000 feet long, from the mouth of the canyon north along the west side of the town to carry the waters of Little Valley Wash to a storage and debris basin of about 100 acre-feet capacity formed by a ring levee. There is no existing Federal project for improvement of Jordan River or Little Valley Wash.

5. In spite of Surplus Canal, Jordan River at Salt Lake City is subject to destructive floods. The peak discharges almost always occur in spring or early summer and result from snow melt sometimes augmented by rain. All of the most important tributaries in Jordan Valley rise in the mountains and enter the river from the east. Several discharge through storm drains in the city section. Flows in the major tributaries are modified by various small storage reservoirs and diversions for irrigation. In recent years run-off below Utah Lake has been the principal factor in peak discharges. The district engineer finds that on rare occasions run-off from summer storms on the area below Utah Lake will produce floods with peak discharges in excess of those caused by snow melt. Utah Lake is utilized as a storage reservoir for irrigation water which requires pumping into Jordan River when the lake is low. Outflows from the lake are controlled by a dam in the Narrows. When the lake is below the established compromise level, little water is discharged except as required for irrigation. Since 1924, lake levels have been continuously below the compromise level. However, during periods of abnormal run-off and high-lake stages, lake outflows can substantially increase flood discharges at Salt Lake City. The observed maximum discharge from the lake since 1902 has been 1,370 cubic feet per second in 1922.

6. Flood records at Salt Lake City consist almost entirely of newspaper accounts and information from private sources. Within the city the channel of Jordan River is no longer an efficient drainage outlet due to the many obstructions and sediment deposits therein. There are places where a discharge of 350 cubic feet per second results in some overflow and a discharge of 1,000 cubic feet per second would cause a general overflow. Surplus Canal has a controlling channel capacity of about 1,100 cubic feet per second in its upper 5 miles within the city and 800 cubic feet per second farther downstream. The largest recent flood occurred in 1917 when the flow at the south city limits was about 1,800 cubic feet per second of which 1,000 cubic feet per second was diverted to Surplus (anal. The 800 cubic feet per second which flowed down the rirer through the city' was increased to about 1,000 cubic feet per second at North

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