TO PROVIDE FOR A SURVEY OF THE SALMON RIVER, ALASKA, WITH A VIEW TO THE PREVENTION AND CONTROL OF ITS FLOODS

MAY 19, 1930.-Committed to the Committee of the Whole House on the state of the Union and ordered to be printed

Mr. Kopp, from the Committee on Flood Control, submitted the following

REPORT

[To accompany H. R. 12121]

The Committee on Flood Control, to whom was referred the bill (H. R. 12121) to provide for a survey of the Salmon River, Alaska, with a view to the prevention and control of its floods, having considered the same, report it to the House and recommend that it do pass.

This bill proposes an expenditure of $800 for a survey of Salmon River, Alaska. The following report on a preliminary survey by the Army Engineer Board explains the necessity for the proposed survey, with detailed description of the project:

WAR DEPARTMENT,

OFFICE OF THE CHIEF OF ENGINEERS,
Washington, April 9, 1930.

Subject: Preliminary examination of Salmon River, Alaska.
To: The Secretary of War.

1. I submit, for transmission to Congress, my report, with the accompanying papers and map, on preliminary examination of the Salmon River, Alaska, with a view to the control of its floods, authorized by the act of February 12, 1929. 2. Salmon River rises among the glaciers at the south end of the boundary between Alaska and Canada and flows in a southerly direction about 25 miles to Portland Canal. Its drainage basin, about 200 square miles in area, consists chiefly of glaciers and steep forested mountains containing rich deposits of gold, silver, and copper ores. The town of Hyder, at the mouth of the river, is the only port on the Alaska side of the boundary serving this area. At this point there are docking facilities for large vessels and the annual commerce of the port amounts to about 9,000 tons. The Bureau of Public Roads, Department of Agriculture, has contributed about $380,000 to the cost of a highway connecting these wharves to the upper valley.

3. Hyder is a town of 500 population located partly in the flood plain of the Salmon River and partly on mud flats at its mouth. During ordinary floods the river rises about 6 feet, and at higher stages, such as occur about once in three years, a considerable portion of the town is flooded. In 1921 the flood waters were, with difficulty, prevented from cutting a new channel directly through the HR-71-2-VOL 4-2

town. Floods of greater magnitude, such as may occur in the future, may cause the entire destruction of the settlement, and the topography is such that no other location of the town site is possible. Local interests have secured a certain amount of flood protection by revetment and channel improvements and the construction of two dikes, the total cost of this work being $24,500. The Bureau of Public Roads has also constructed one dike at a cost of $8,000. These works are not of a permanent nature and do not afford adequate protection against future floods.

4. The district engineer is of the opinion that suitable protection can be obtained by the construction of a dike or levee along the river bank and by clearing a flood way to permit the flood waters to pass into Portland Canal at a safe distance from Hyder. Such Improvement would protect the town and also 100 acres of the flood plain above it, which is the only suitable area for future expansion of the town. While the cost of this work is roughly estimated at $80,000, a survey will be necessary to formulate detailed plans and make an accurate estimate of the cost

5. While this improvement would be of value primarily to the town of Hyder, the district engineer points out that it would protect property belonging to the United States which cost nearly $50,000 and is necessary to the preservation of the only United States port serving the adjacent mining areas. In view of these facts he considers that the proposed improvement is both national and local or Territorial in scope; and that 80 per cent of the cost should be borne by the United States and 20 per cent by local interests. He recommends that a survey be authorized at an estimated cost of $800. The division engineer concurs.

6. The report of the district engineer has been referred, as required by law, to the Roard of Engineers for Rivers and Harbors, and attention is invited to its report herewith, agreeing in general in his views.

7. After due consideration of the above-mentioned reports, I concur in the recommendations of the Board of Engineers for Rivers and Harbors. The protection of this locality from destructive floods appears to be desirable, if it can be obtained at a reasonable cost, but there is not sufficient information at the present time to determine the cost of the proposed project or the economic justification for its construction. Without making at this time the final determination of the advisability of the project or of the proper division of the costs between the United States and local interests, I report that a survey of the Salmon River, Alaska, with a view to the control of its floods is deemed advisable at an estimated cost of $800.

LYTLE BROWN,

Major General, Chief of Engineers.

REPORT OF THE BOARD OF ENGINEERS FOR RIVERS AND HARBORS

SYLLABUS

The Board of Engineers for Rivers and Harbors recommends that a survey of Salmon River, Alaska, with a view to the control of its floods, be authorized, at an estimated cost of $800.

[Third indorsement]

BOARD OF ENGINEERS FOR RIVERS AND HARBORS,
Washington, D. C., March 12, 1980.

To the CHIEF OF ENGINEERs, United StaTES ARMY:

1. The following is in review of the report on preliminary examination of Salmon River, Alaska, with a view to the control of its floods, which was authorized by the act of February 12, 1929, in accordance with the provisions of the act of March 1, 1917.

2. Salmon River is a stream 25 miles long in southeastern Alaska. It originates from glaciers along the Alaska-Canadian border and flows in a southerly direction to Portland Canal. Its drainage basin comprises 200 square miles, of which an area of 50 square miles is covered with glaciers and the remainder is precipitous mountains well covered with spruce up to the timber line. The river valley is from one-half to 1 mile wide and bordered with abrupt mountain slopes. The floor is composed of gravel and silt. Half of the width contains a dense timber growth and in the other half the stream is located, its channels shifting continually because of the accumulations of drift and silt. The basin is rich in ores, containing gold, silver, and copper, the most important properties being near the head of the valley in British Columbia. Supplies and products sent to and

from the developments in this area are carried over a road extending from the international border to the town of Hyder, at the mouth of Salmon River, where two commercial wharves afford docking facilities for large vessels. The annual commerce of this port amounts to about 8,800 tons, 68 per cent of which is exported lumber, 22 per cent imported general merchandise, and 9 per cent imported fuel. The road connecting this point with the upper valley was built by the Bureau of Public Roads, Department of Agriculture, at a cost of $431,749.65, the amount contributed by the United States being $380,429.65. Its connection with the docks at Hyder is by a trestle constructed at a cost of $28,500.

3. Hyder is a town of 500 population located partly in the flood plain of Salmon River and partly on mud flats at the mouth. The flow of the river at the town varies from about 1,100 to 20,000 cubic feet per second. The river rises about 6 feet during ordinary floods. At the higher stages, such as occur about once in three years, it inundates about 200 acres of the town and has caused damage to the extent of about $1,000 per year.

4. In 1921 the flood waters were with difficulty prevented from cutting a channel directly through the town. Only short-time records are available, and it is quite possible that floods of much greater magnitude may occur in the future. Such floods might destroy the entire town, which is the only American port serving a valuable mining area. The topography is such that no other location of the town site is possible. A certain amount of protection has been provided by two dikes, revetment, and channel improvements made by local interests in 1921 at a cost of $24,500, and by one dike constructed in 1925 by the United States Bureau of Public Roads at a cost of $8,000. These works were constructed to prevent the stream from scouring out a new channel through the town site. but they are not of a permanent nature and do not afford adequate protection, 5. The district engineer believes that suitable protection can be obtained by the construction of a dike or levee 4,000 feet in length along the river bank and by clearing a flood way to permit the river to pass into Portland Canal at a safe distance from Hyder. This improvement would protect the town and also 100 acres of the flood plain above it which is required for future expansion, as there is no other suitable level area in the vicinity. The estimated cost of the work is $80,000, with $1,000 annually for maintenance. This estimate was made without a survey and should be considered only as a rough approximation. The United States Government property within the area which would be protected consists of one-half mile of road costing about $10,000, buildings worth $10,000, and the dock approach, costing $28,500. In addition to the protection afforded this property, it is estimated the improvement will prevent scour and silting near the wharves which if allowed to continue would necessitate maintenance expenditures amounting to $30,000 during the next 20 years. A further matter of national importance is the interest the Government has in the development and growth of commerce at this port. Due to these Federal interests the district engineer believes that the proposed improvement is both national and local or territorial in scope and that 80 per cent of the cost should be borne by the United States and 20 per cent by local interests.

6. He reports that there is no possibility of coordinating the improvement with water power or other general improvements. Impounding or regulating works are impracticable, as long dams would be required, and the pools would be rapidly filled with silt and débris carried by the stream in times of flood.

7. The district engineer considers it desirable that further investigations be made by the Federal Government because its interests are involved in the project and because of the lack of local engineers experienced in this type of work. The preparation of more detailed plans and of a more accurate estimate will require a survey. He recommends that such a survey be authorized at an estimated cost of $800. The division engineer concurs.

CONCLUSIONS AND RECOMMENDATIONS OF THE BOARD OF ENGINEERS FOR RIVERS AND HARBORS

8. Without making at this time a final determination of the advisability of flood-control works or of proper division of their costs between the United States and local interests, the board concurs in general in the opinions of the district and division engineers and recommends that a survey be authorized at an estimated cost of $800. For the board: