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Table 9.-Pertinent descriptive data, alternate plan, Rosiclare, I.
Location:
River.

Ohio.
Bank..

Right. River miles below Pittsburgh, Pa.

891.4 to 892.5. Area protected.-

Rosiclare, III., and adjacent mine

properties.
Protection works:
Length:
Levee (new), section 1

895 linear feet.
Levee (new), section 2.

987 linear feet. Concrete wall, section 1.

1,526 linear feet. Average height: Levee (new), section 1.

23.1 feet. Levee (new), section 2.

22.3 fect. Concrete wall, section 1.

16.2 feet. Embankment: Section 1

63,300 cubic yards. Section 2

64,400 cubic yards. Drainage structures..

6. Movable closures..

2. Pumping plant: Drainage area.

1,000 acres. Number...

1. Capacity:

135 cubic feet per second. Interior run-off..

15,700 gallons per minute.

0.83 inch per day. Sanitary sewage.

13 cubic feet per second.

11,300 gallons per minute. Total...

$38 cubic feet per second.

117,000 gallons per minute, 62. The alternate plan differs from the selected plan in that 1,526 linear feet of concrete flood wall is substituted for earth levee in section 1. The primary reason for considering this construction was to determine if the savings in rights-of-way and damage cost would be sufficient to counterbalance the higher cost of the concrete wall. The drainage and other structures which would be required under the alternate plan are comparable with those described for the selected plan. Utility and transportation alterations are the same under both plans. There is no essential change in the pumping-plant installation. Section 2 of the protection works is identical under both plans. The top of the wall and levee are at the same elevation under the alternate plan, 367.5 (mean sea level), which is the same grade elevation used for the selected plan.

63. Estimates of first cost and annual charges.-Estimates of first cost: There is shown in table 10 a summary of the Federal and nonFederal first costs for both the selected and the alternate plans of improvement. The costs used reflect prices as of May 1946. Detailed estimates of costs are given in the appendix.'

64. Estimates of annual charges: A summary of annual charges for both the selected and alternate plans is shown in table 11. A more detailed analysis of annual charges is given in the appendix. The amortization period used for the levee and flood wall is 50 years and for the pumping installation, 35 years. The item for inspection and surveys included as a Federal charge covers costs of work of that type necessary for a proper supervision of the maintenance and operation procedure of local interests.

1 Not printed.

Table 10.-Summary of estimates of first cost, flood protection, Rosiclare, III.

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Table 11.-Estimates of annual charges, selected and alternate plans, flood protection,

Rosiclare, N.

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65. Estimates of average annual benefits.-Average annual damage estimates (par. 39) are representative of present conditions of development and, with the exception of negligible amounts of damage, are incurred only within the area which is given protection. Further development within the protected area which would take place independently of the provision of flood control is problematical and has not been considered. The flood-control-improvement plan would provide, contingent on the correctness of present flood-frequency knowledge, complete flood protection for the area. Consequently, the average annual direct flood damage would represent the average annual direct flood damage prevented by the proposed works. This value for both plans is $40,300.

66. The average annual indirect flood damage prevented, estimated separately from the direct losses, consist principally of the elimination of loss of profit and wages to the fluorspar mining industries in the locality. These indirect benefits, like the direct losses prevented, would be equivalent for all practical purposes to the indirect damage. The estimated average annual indirect flood damage prevented by the protection works is $36,700. The total direct and indirect average annual flood damage prevented is $77,000. Supporting information, data, and computations dealing with the determination of benefits are given in the appendix.

67. The intangible benefits accruing to the project are preservation of human life, enhancement of the general welfare and social security of the population, improvement of sanitary conditions and protection against epidemics. While no monetary value has been placed on these benefits, they are nevertheless important in the locality under consideration.

68. Justification of project and allocation of costs.—The ratios of annual charges to average annual benefits are shown in table 12. Both the selected and the alternate plans of improvement are economically justified by a wide margin.

TABLE 12.Comparison of annual charges and average annual benefits, selected

and alternate plans, flood protection, Rosiclare, III.

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69. The benefits accruing to the plan of protection are purely local and are confined to the area protected. It is deemed proper that local interests assume that portion of the cost which is necessary to secure rights-of-way for the project and which result from damages to existing local improvements by the construction of the works. Those latter consist principally of the movement or replacement of buildings which are located within the rights-of-way limits of the project. In addition, local interests would be required to pay the costs of miscellaneous utility alterations, minor road relocation, the removal of a coal bin and railroad spur thereto, and the reconstruction of the coal bin.

70. Flood-channel delineation.-Works for the protection of Rosiclare could be rendered less effective and to a certain extent endangered by encroachment in the flood plain of such nature as to reduce the flood-carrying capacity of the Ohio River, such as the construction of bridge approaches. Although no such works are known to be planned at this time, in order to assure against such encroachment in the future it is deemed advisable that any works which would appreciably limit the flood-carrying capacity of the Ohio River in this locality should be prohibited. The Ohio River is a navigable stream. Consequently, any new works projected by any agency along the stream are subject to approval and the issuance of a permit for construction by the Secretary of War. This prerogative of the Federal Government is considered a sufficient safeguard for protection against deleterious encroachment in the floodway.

71. Discussion.—Rosiclare, Ill., and the fluorspar mines and mills in the vicinity thereof are damaged severely by Ohio River floods. Major floods inundate the business district of Rosiclare and a considerable portion of residential area. Fluorspar mines and ore-processing mills are flooded. Flood frequencies are such that a comparatively large average annual flood damage results. The plan of improvement which would most effectively eliminate these damages involves the construction of two sections of earth levee with necessary appurtenances, such as road-closure structures, drainage outlets, and works for the disposal of interior run-off and sewage during floods. The levee would provide protection against a recurrence of the 1937 flood with a minimum freeboard of 3 feet. Works for the disposal of interior runoff and sewage during floods have reasonably ample capacity to serve those purposes.

72. The total estimated cost of the improvement is $462,000, of which $144,300 is for levee construction, $77,100 is for riprap slope protection, $70,600 is for road-closure structures, $31,000 is for drainage structures and storm-sewer alterations, $42,000 is for a pumping plant and appurtenant works, $91,400 is for rights-of-way and damages due to the construction works, and $5,600 is for miscellaneous utility alterations and road relocation. (See table 10.) The estimated total annual charges are $24,400. (See table 11.) The estimated average annual benefits are $77,000. The ratio of annual charges to average annual benefits is 1 to 3.16. The project is economically justified by a wide margin.

73. The alternate plan considered involves the replacement of a portion of earth levee with a concrete flood wall in the river section (section 1) where, by the use of the wall, many existing buildings could be left undisturbed. It was found that the total cost of the improvement would be increased to $677,000, or $215,000 greater than allearth levee construction, with no attendant increase in the benefits ascribable to the project. (See table 10.)

74. Responsible interested parties have expressed the desire for both a concrete wall and an earth levee. A location for the protection works where they will cause the least interference with existing structures is desired. A flood-wall location was suggested for the river section (section 1), which would place the structure close to normal waters edge and, for a considerable portion of its length, riverward from the top of the high bank. A wall constructed in the suggested location would be much higher than the one considered in the alternate plan and would be much more costly. No specific location was formally suggested for the earth levee. The location for the levee under the selected plan of improvement (see enclosure 2) was chosen so as to permit the removal of the fewest and least costly of the existing improvements consistent with the safety of the structure. It is believed that local interests will agree to the installation of the proposed plan of improvement.

75. Local interests should be required to furnish without cost to the United States all rights-of-way and flowage easements; and should hold the United States free of damages resulting from the construction of the works. Further, local interests should be required to maintain and operate the works in accordance with regulations prescribed by the

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Secretary of War. The estimated first cost which would be incurred by local interests is $97,000. This estimate does not take into account any grants which local interests might receive. It appears that Rosiclare has the legal ability and willingness to fulfill the requirements of local cooperation recommended herein.

76. Conclusions.—The plan found most suitable for the protection of Rosiclare, Ill. against floods consists of a compacted earth fill levee supplemented by works for the disposal of interior run-off and sewage during the floods. The plan is economically justified by a wide margin.

77. Recommendations.-It is recommended that a project for construction of an earth levee and supplemental works for the disposal of interior run-off and sewage during floods, substantially as outlined in this report, be adopted for the protection of Rosiclare, Ill, against floods.

78. It is further recommended that, prior to the expenditure of Federal funds for the work, local interests be required to furnish assurances satisfactory to the Secretary of War that they will (1) provide without cost to the United States all lands, easements, and rightsof-way necessary for the construction of the project, (2) hold and save the United States free from damages due to the construction of the works, and (3) maintain and operate the works after completion in accordance with regulations prescribed by the Secretary of War. The estimated total non-Federal first cost and total annual charges to be borne by local interests are $97,000 and $9,400, respectively.

79. The estimated total Federal first cost is $365,000. The economical and advantageous prosecution of the work would entail an initial allotment of the entire Federal first cost.

B. B. TALLEY,
Colonel, Corps of Engineers,

District Engineer.

[First endorsement)

DIVISION ENGINEER,

OHIO RIVER DIVISION,

Columbus, Ohio, July 23, 1946. To: The Chief of Engineers, United States Army.

The division engineer concurs in the recommendations of the district engineer

B. C. Dunn,
Colonel, Corps of Engineers,

Division Engineer.

List OF ENCLOSURES MADE IN CONNECTION With REPORT OF THE DISTRICT

ENGINEER

(Only enclosures 1 and 2 are printed)
Enclosure 1. Map-General plan.
Enclosure 2. Map (in 3 sheets)- Plan, profile, and sections.
Enclosure 3. Appendix-Detailed estimates of cost with 3 plates as follows:

Plate 1. Alternate plan.
Plate 2. Stage frequency, dam 51.

Plate 3. Stage-damage relation.
Enclosure 4. Record of public hearing with exhibits.

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