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198. Estimates of first cost and annual charges.—The estimated costs, including engineering, overhead, and contingencies, and the estimated annual charges for the project are shown in table No. 36. The estimates of costs and annual charges are shown in detail in appendix No. IV.1
Table No. 36.-Estimated costs and annual charges, Pope County levee district
No. 1 and Conway County levee districts Nos. 3 and 7, Arkansas
$1, 331, 000 Drainage structures
77, 000 Cut-off channel.
34, 000 Channel clearing
16, 000 Total Federal first cost estimated appropriation of public funds necessary for the execution of the project).
1, 458, 000 Non-Federal first cost: Lands and rights-of-way, including damages.
96, 000 Replacement of bridge on old U. S. Highway No. 64..
33, 000 Total non-Federal first cost...
129, 000 Total cost of project---
1, 587, 000 Federal investment (construction period less than 1 year)
1,458, 000 Federal annual charges: 3 percent of Federal investment..
43, 740 Amortization of Federal investment.
19, 600 Total Federal annual charges.
63, 340 Non-Federal investment..
129, 000 Non-Federal annual charges: 4 percent of non-Federal investment
5, 160 Amortization of non-Federal investment.
1, 350 Maintenance of levee, maintenance and operation of drainage structures, and maintenance of channel..
4, 570 Total non- n-Federal annual charges.
11, 080 Total annual charges..
74, 420 199. Estimates of average annual benefits.--- The benefits that would result from construction of the project consist of the direct and indirect flood losses prevented, a portion of the enhancement in land values which would result from flood protection, and some intangible benefits. In addition to protecting the area from floods of experienced magnitude, the project would provide protection from a larger design food which is assumed to occur once within the economic life of the project (40 years). The estimated prevented direct and indirect losses from such a flood have been considered as a benefit. The estimated evaluated average annual benefits are given in table No. 37. Table No. 37.-Annual benefits, Pope County levee district No. 1 and Conway
County levee districts Nos. 3 and 7, Arkansas Prevented direct losses, experienced floods.
$50, 760 Prevented indirect losses, experienced floods
6, 680 Prevented direct and indirect losses, design flood.
8, 530 Enhancement in land values..
Total evaluated annual benefits..
200. Justification of project and allocation of costs.- The total annual charges amount to $74,420 and the total evaluated annual benefits amount to $69,970. The ratio of annual charges to annual benefits is 1 to 0.94. The benefits which would result from the improvement would be largely local in character; therefore, if the project is authorized for construction, local interests should be required to participate to the extent provided by law for similar projects, and in addition they should be required to replace the bridge on the old United States Highway No. 64. The estimated cost of meeting these requirements is $129,000.
201. Discussion and conclusions. There is a flood problem in Pope County levee district No. 1 and Conway County levee districts Nos. 3 and 7 because the existing levees are not adequate to withstand major floods on the Arkansas River, because they do not provide complete protection from lesser floods on the Arkansas River, and because they do not provide protection from floods on Point Remove Creek. The levees are overtopped, as a unit, by the Arkansas River when the Arkansas River gage at Morrilton reaches a stage of about 29 feet and a considerable portion of the area is inundated by backwater from the river when the stage exceeds 23 feet. The maximum flood of record on the river occurred in April 1927 when the Morrilton gage reached a stage of 32 feet. The flood of May of this year (1943) reached a stage of 30.8 feet. In addition to the Arkansas River floods, a portion of the area is subject to frequent floods from Point Remove Creek. The levee grade for the existing (authorized) project was based upon & 3-foot freeboard above the computed flow line of the flood of April 1927 as it would be confined by the authorized levee. The authorized project would provide protection from floods on the Arkansas River only. The large flood of this year (1943) exceeded by 5.0 feet the stage of the 1927 flood on the gage at Fort Smith, Ark., about 141 river miles upstream from Morrilton, and was 1 foot higher than the 1927 flood on the gage at Dardanelle, Ark., about 35 river miles upstream from Morrilton. The 1927 flood was augmented throughout the entire reach from Fort Smith to Morrilton by large tributary inflow resulting from intense rainfall over the intervening drainage area, whereas the peak discharge of the May 1943 flood decreased as it traveled downstream. If similar conditions had existed in May of this year, the resulting flood would have exceeded that of 1927 at Morrilton. If the levee along the Arkansas River were constructed to the grade established in the existing project, a repetition of the 1943 flood, under conditions such as existed during the 1927 flood, would overtop the levee throughout its entire length. Moreover, a considerable portion of the area is subject to very frequent floods of long duration from Point Remove Creek. In view of the above-mentioned circumstances it is considered advisable to modify the existing project to provide for a higher levee grade for protection from Arkansas River floods, and for the continuation of the levee along Point Remove Creek in order to provide protection from floods on that stream.
202. The project proposed herein would provide complete protection for 19,660 acres of rural land in Pope County levee district No. 1 and Conway County levee districts Nos. 3 and 7 from floods of the Arkansas River and Point Remove Creek. Although construction of the authorized levee project was deferred owing to the
failure of the local interests to meet the requirements of local cooperation, the recent severe flood and its resulting extensive damage have influenced the attitude of the officials of the districts so that they now strongly desire the proposed improvement. It is therefore believed that they would meet the requirements of local cooperation prescribed by law for other similar projects, as well as replace the bridge on old United States Highway No. 64. The estimated cost of the proposed project is $1,587,000, of which $1,458,000 is the Federal cost as compared with a Federal cost of $603,000 for the existing flood-control project. The estimated total cost of the project exceeds the estimated value of the property which would be protected. However, economic studies indicate that it is reasonable to expect property values in the area to increase to the extent that they would exceed the estimated cost of the project if flood protection is provided. The estimated annual charges and evaluated annual benefits are $74,420 and $69,970, respectively, resulting in a cost to benefit ratio of 1 to 0.94. The total evaluated benefits are slightly less than those required for economic justification; however, the intangible benefits which would result from the proposed project, such as the elimination of existing hazards of life and health, are considered to be of enough importance to render the project economically justified. It is therefore believed that the existing flood-control project should be modified as proposed herein.
203. Conway County levee district No. 6, Arkansas-Description of area.-Conway County levee district No. 6 is in Conway County, Ark., and is located on the inside of a bend on the right bank of the Arkansas River between miles 224.5 and 219.3, opposite the city of Morrilton, Ark. The area which would be protected by the proposed project contains 1,840 acres of agricultural land, of which 1,720 are under cultivation, 90 are pasture and idle land, and 30 are wooded. The general location of the area is shown on plate No. VIII.
204. Economic development. The area under consideration is characteristically agricultural. The lands are highly developed, and modern farming methods are used. The principal crops are cotton, corn, soybeans, and alfalfa and other hays. The average annual value of crops is $65,900, or an average of $38.31 per cultivated acre. State Highways Nos. 9 and 154, paved routes, and State Highway No. 113, gravel surfaced, as well as a network of county roads, serve the area. Portions of the area are served by an electrical distribution system and there are telephone lines located along the highways. The nearby city of Morrilton, with a population of 4,608 inhabitants according to the 1940 census, is the county seat of Conway County and serves as a convenient marketing and shipping center for the area. The total value of property in the area is estimated to be $184,800.
205. Floods and flood problems.-Flooding from the Arkansas River may occur at any time of the year, but floods are more prevalent during the months of April, May, and June. The existing levee in the area provides protection from moderate floods but is endangered at a stage of about 26 feet on the Morrilton gage. It is estimated that floods on the Arkansas River which would cause failure of the existing levee occur with a frequency of about once in 5 years. Levees appear to be the only type of local flood protection that would be practicable
for the area.
206. Flood damages.-The principal direct flood damages in Conway County levee district No. 6, based on a repetition of experienced floods under present conditions of development, consist of crop losses and damage to land and farm improvements, roads and bridges, and the levee system. The indirect losses consist primarily of loss of business and the costs of evacuation, relief, and rehabilitation. It is estimated that the average annual direct losses total about $13,640 and that the average annual indirect losses amount to about $1,120. In addition to the direct and indirect losses, flooding in the area causes intangible losses by upsetting orderly processes and adversely affecting social security. These losses include impairment of health, mental distress and human suffering, and deterrence to improvement of the area, both from a farming and living standpoint. During the flood of May 1943, four persons lost their lives in the area while attempting to reach Morrilton by boat.
207. Existing flood-control improvements.--Conway County levee district No. 6 was organized in June 1916 and constructed at a cost of $10,585 about 4.4 miles of levee along the right bank of the Arkansas River to prevent overflow of lands within the district. Subsequent to the flood of April 1927, when the original levee was overtopped and badly damaged, the district issued bonds and made partial repairs at a cost of $11,554, and further repairs were made by the Federal Government. The levee failed during the flood of 1935 and was damaged during the floods of 1938 and 1941. It was repaired in each instance by the Federal Government. The flood of this year caused extensive damages to the levee, which the Federal Government is now repairing. It is estimated that at the end of this year the total Federal expenditures for repairs and high-water inspection and maintenance for the levee will amount to approximately $67,500. The levee has proved inadequate to protect the area from major floods on the Arkansas River.
208. Prior favorable report.— A survey report for flood control in Conway County levee districts Nos. 1, 2, 6, and 8 was made under authority of resolutions adopted May 14 and November 12, 1941, by the Committee on Flood Control of the House of Representatives of the United States. The report was submitted by the district engineer on April 30, 1942. The report, which has not been published, was reviewed by the Board of Engineers for Rivers and Harbors, and the construction of flood protective works substantially as outlined in the report has been recommended by the Chief of Engineers at an estimated cost to the Federal Government of $662,000, of which $187,000 was for Conway County levee (listrict No. 6. The improvements have not been authorized for construction.
209. The plan of improvement outlined in the survey report for the protection of Conway County levee district No. 6 provided for raising and enlarging the existing levee and constructing new levee where the existing one was not suitably located, together with appurtenant drainage structures. The grade of the levee would be 3 feet above the computed flow line of the flood of April 1927 as it would be modified by the presently authorized and approved reservoirs and confined by the levees proposed in that report.
210. Description of project. The plan of improvement for Conway County levee district No. 6, as now proposed, provides for a compacted
earth-fill levee along the right bank of the Arkansas River between miles 224.6 and 219.3. The levee would follow in general the alinement of the existing levee and would be 4.4 miles in length, of which 2.7 miles would be enlargement with an average height of 16.3 feet and 1.7 miles would be new levee with an average height of 16.6 feet. The levee would have a crown width of 10 feet and side slopes of 1 on 3. The levee would have a 1%-foot freeboard above a confined flood profile based on a flow of 800,000 cubic feet per second, which is greater than any experienced flow in the locality. The authorized and approved reservoirs, when completed, would provide an additional desirable freeboard. One drainage structure would be extended and one new structure built. Local run-off would cause some interior flooding during flood periods when the drainage structure floodgates would be closed. The levee would provide protection from floods of the Arkansas River for 1,840 acres of agricultural land, of which 1,720 are under cultivation. Pertinent features of the plan are shown on sheet 29 of appendix No. I.
211. The presently proposed project for Conway County levee district No. 6 differs from the plan of improvement outlined in the prior favorable report in that it provides for a levee grade about 2.5 feet higher and a compacted earth-fill levee.
212. Estimates of first cost and annual charges.-- The estimated costs, including engineering, overhead, and contingencies, and the estimated annual charges for the project are shown in table No. 38. The estimates of costs and annual charges are shown in detail in appendix No. IV.
Table No. 38.--Estimated costs and annual charges, Conway County levee district
No. 6, Arkansas
$337, 000 Drainage structures.
14, 000 Raising highway bridge (Morrilton) across the Arkansas River.. 1 20, 000 Total Federal first cost (estimated appropriation of public funds necessary for the execution of the project)-
2 371, 000 Non-Federal first cost: Lands and rights-of-way, including damages.
20, 000 Raising approaches to highway bridge (Morrilton) across the Arkansas River..
Total non-Federal first cost
394, 000 371, 000
Total cost of project---
3 percent of Federal investment
11, 130 4, 990
Total Federal annual charges.
Includes only a part of the cost of the alteration; the remainder is included in the cost estimate for the