SECTION II - PROJECT DESCRIPTION

2.01 LOCATION

Wappapello Lake is located on the Upper St. Francis River in the southeastern part of Missouri. The dam site lies 22 miles southeast of Greenville, 1 mile southwest of Wappapello and 16 miles northeast of Poplar Bluff. Although most of the lake is in Wayne County, a small southern portion extends into Butler County. The dam lies approximately 8 miles east of U.S. Route 67 and 12 miles north of U.S. Route 60. Highways providing direct access to the lake include: U.S. Route 67 running north-south on the west side of the lake, State Route D and BB running north-south on the east side of the lake, State Routes T, KK, W, PP, RA and 172 provide access to the southern end of the lake, and State Route 34 running east-west and State Routes 143, FF and F provide access to the northern end of the lake. The location of the lake and adjacent lands is shown on PLATE 2, "Land Classification Map", and the regional highway network is presented on PLATE 4, "Road Network".

2.02 LAKE DATA

1. General




Construction of the dam was started in September 1938 and was completed in June 1941. The dam is a rolled earth-fill structure with a controlled outlet and an emergency spillway in the right abutment. A 125 KVA hydroelectric plant provides power for operating the dam gates and lights and other lake purposes. Pertinent data related to lake features and additional information are presented in TABLE 1.



TABLE 1 PERTINENT DATA SUMMARY WAPPAPELLO LAKE

LAKE
Drainage Area	1,310	sq.mi.
Conservation Pool
Elevation (Top)	354.74	ft. NGVD
Surface Area (Top)	5,200	acres
Storage Capacity	30,900	acre-feet
Runoff Capacity	0.44	inches
Recreational Pool
Elevation (Top)	359.74	ft. NGVD
Surface Area (Top)	8,400	acres
Flood Pool
Elevation 354.75-	394.74	ft. NGVD
Surface Area (Top)	23,200	acres
Storage Capacity	613,200	acre-feet
Runoff Capacity	8.78	inches
Maximum Regulated Outflow	10,000	c.f.s.
Surcharge Pool
Elevation 394.75-	413.74	ft. NGVD
Surface Area (Top)	32,100	acres
Storage Capacity	1,134,600	acre-feet
Runoff Capacity	16.24	inches
Freeboard
Elevation 413.75-	419.74	ft. NGVD
Dam	Earth Fill
Elevation, Top of Dam	419.74	ft. NGVD
Maximum Height above Streambed	109	feet
Length of Crest	2,700	feet
Crown Width	30	feet
Maximum Base Width	765	feet
Volume of Earth in Dam	2,300,000	cu. yd.
Spillway
Length	740	feet
Elevation of Crest	394.74	ft. NGVD
Outlet Structure
Length of Structure	724	feet
Gates	3 gates each	10 ft x 20 ft
Elevation of Gate Sill	338.1	ft. NGVD
Number of Conduits	1	each
Inside Diameter of Conduits	22	feet

1/ * NGVD - National Geodetic Vertical Datum





2. Basin Hydrologic and Climate Summary



1. General. The climate of the area is mild, with the average annual temperature about 57.2° Fahrenheit. The first killing frost normally occurs in mid-October and the last frost occurs in April. The average temperature for January is 34°; for July, it is 79°. The annual rainfall is well distributed throughout the year at an average 46.79 inches. Snowfall is moderate, averaging 8 to 12 inches, and is the heaviest in January and February. The average growing season is 185 days. Regional climatic averages are presented in Table 2.



2. Precipitation. The normal annual rainfall in the St. Francis Basin in the Ozark uplands is about 46 inches per year. Normal monthly rainfall varies from about 2.6 to 5.0 inches in the region, the heaviest occurring in the period March through July. In the southern portion, or that part which lies in the alluvial valley of the Mississippi River, the normal monthly rainfall varies from about 2.8 to 6.0 inches, with the heaviest occurring during the months November through May. The maximum annual total for one station was observed at Kennett, Missouri, in 1957 when 86.75 inches of precipitation was recorded. A minimum station total of 22.37 inches was recorded at Arcadia, Missouri, in 1953. Since 1940, the maximum annual rainfall over the reservoir area has been 67.30 inches in 1945 with a runoff of 52.9 percent. The minimum rainfall occurred in 1953 when 23.72 inches was recorded over the same area with a runoff of 33.8 percent. Average annual snowfall is about 8 to 12 inches in the reservoir area, diminishing to about four inches in the southern portion of the basin. Snow rarely remains on the ground more than a few days at a time.


TABLE 2 REGIONAL CLIMATIC AVERAGES

Month	Average Monthly High Degrees Fahrenheit	Average Monthly Low Degrees Fahrenhiet	Average
January	47.80	24.10	31.40
March	62.40	35.80	52.20
May	79.70	54.70	61.40
July	91.80	64.50	76.40
September	84.00	55.30	67.50
November	57.70	31.90	37.10
Annual Temperatures
Annual Days Over 90°F:		55 to 60
Annual Days Under 32°F:		70 to 110
Precipitation:
Annual Average Rainfall:		46.79"
Annual Average Snowfall:		8 to 12 inches

1/ Ozark Foothills Regional Profile Dec. 1983, Ozark Foothills Regional Planning Commission.

3. Evaporation. The average annual lake evaporation is about 33.4 inches. The pool elevation versus surface area, for use in calculating evaporation from the pool, is presented as TABLE 3.
   
   TABLE 3 WAPPAPELLO LAKE ELEVATION - SURFACE AREA DATA
   

   Elevation (feet NGVD)	Surface Area (acres)
   312.74	0
   319.74	58
   324.74	174
   329.74	190
   334.74	234
   339.74	880
   344.74	1400
   349.74	2600
   354.74 (Top Conservation Pool)	5200
   359.74 (Recreation Pool)	8400
   364.74	10400
   369.74	12400
   374.74	15200
   379.74	16900
   384.74	18600
   389.74	20800
   394.74 (Top Flood Control Pool)	23200
   399.74	25200
   404.74	27800
   409.74	30000
   413.74 (Top Surcharge Pool)	32100
   419.74 (Top of Dam)	35100

4. Floods. The history of the St. Francis Basin indicates that it has been subject to periodic floods, with most of the flood damage confined to agricultural areas. The August 1915 flood exceeded all previous records on the upper St. Francis with a peak flow past Wappapello estimated at about 85,000 cubic feet per second. This flood was one of the most destructive of record in the St. Francis Basin, causing an estimated damage of $5,000,000. The flood of May 1933 overflowed approximately 207,000 acres of which 91,000 acres were cultivated with estimated damages of about $826,000. The March 1935 flood produced the highest stage of record at St. Francis, Arkansas. This flood overflowed an area of 337,000 acres including 151,000 cultivated acres, with an estimated damage of $2,000,000. The January 1937 flood produced the greatest flow on the lower St. Francis, being the culmination of a series of rains totaling approximately 17 inches in 25 days. It caused an estimated damage of $600,000 resulting from an overflowed area of 371,000 acres of which 195,000 acres were cultivated. In 1943 and 1945, with the dam in place, flood damages were reduced by 8 and 14 million dollars, respectively.



3. Lake and Shoreline. The lake is confined by the steeply sloped Ozark Hills. The main portion of the lake is formed by the St. Francis River Valley. The topography varies due to the many small tributaries which enter the river above the dam site. This results in ravines, valleys, and an irregular shoreline. Many of the slopes are timbered. The lake has a water surface area of 8,400 acres at recreation pool with a shoreline 180 miles in length. The pool at this elevation extends approximately 28 miles above the dam and is a maximum of 47 feet deep. TABLE 2 contains pertinent elevation and surface area data.



4. Project Structures. The complete structure consists of an earth dam, a concrete outlet structure, and a concrete emergency spillway. The dam is a rolled earth fill with riprap stone protection on the slopes. It has a length of 2,700 feet and height of approximately 109 feet above the old channel bed.




The crown is 30 feet wide and carries a roadway 22 feet wide. Supplementing the main dam are three small auxiliary dikes that rim the left abutment with a total length of about 1,700 feet and a maximum height of approximately 30 feet.



The outlet control structures are 400 feet south of the dam in the right abutment. The conservation pool weir, with crest elevation at 354.74 NGVD and a length of 70 feet, is pierced by five sluices, each 6 feet wide and 7.5 feet high, with invert elevation at 338.74 NGVD. The intake section of the control structure lies within the gate house and contains three water passages, each controlled by a motor-operated, tractor-type gate, 10 feet wide and 20 feet high. The outlet works also contain a penstock. This provides for the operation of 125 KVA hydroelectric unit to furnish power and lights for the dam, gate house, and some recreation facilities. A diesel engine directly connected to a 50 KVA generator serves as a stand-by unit. An uncontrolled emergency spillway is provided in a natural saddle about 1,200 feet south of the south end of the dam. This concrete structure founded on bedrock, has a 740 foot long spillway with a crest elevation of 394.74 feet NGVD.

2.03 LAKE REGULATION

1. General Objective. The objective is to provide flood protection to downstream interests during wet periods while maintaining the pool as nearly as possible at rule curve elevation. Rule curve is defined as the elevation at which a reservoir is desired to be maintained to accommodate reservoir functions (other than flood control) plotted against the time of year. Plate 23 provides information on fluctuation of reservoir levels and hydrological data.



2. Regulation Procedure.



1. Non-crop Season. The non-crop season is considered to exist from 1 January through 31 March. During this period the release rate may reach the maximum of 10,000 cubic feet per second (cfs) independent of pool elevation. Rate of release shall match rate of inflow as nearly as possible up to 10,000 cfs and be maintained at this rate until the storm inflow is depleted or the pool approaches its lower limit. Some discretion is allowed in the discharge rate at elevations below 379.74 feet NGVD, but when this elevation is exceeded 10,000 cfs must be discharged.



2. Crop Season. The crop season is considered to exist from 1 April through 31 December, the date when all crops have normally been harvested. During this period the maximum non-damaging flow rate at Fisk, Missouri, and St. Francis, Arkansas, is 3800 cfs. The outflow from the Lake must be controlled in order not to exceed the 3800 cfs at Fisk and St. Francis unless the pool level should exceed one of the following elevations, at which time the outflow would be increased to a constant discharge rate as noted. Reservoir capacity and surface area data are provided in Table 3.

   Period	Elevation (NGVD)	Constant Discharge (cfs)
   1 Jan-31 May	379.74	10,000
   1 June-31 Oct	391.74	7,000
   1 Nov-1 Dec	388.74	7,000

   
   

2.04 VISITATION DATA

1. General. Visitation at Wappapello Lake increased steadily from 1958, when data collection began, to 1998. Although visitation has remained relatively stable (2 million visitors annually) for the past ten years, increases in the number of visitors are anticipated due to expanding regional development. Year to year variations in actual visitation can be attributed to changes in weather conditions, fluctuations in lake levels, cost and supply of gasoline, general economic conditions, and the level of facility development occurring on the lake. Recreational opportunities will be continually reevaluated to insure maximum use by the public.



2. Past and Current Visitation. Wappapello Lake has established a zone of influence as shown on PLATE 3. The 1984 Visitor Use Survey provided data which showed that 43% of lake visitors travel a distance greater than 75 miles to reach the lake, 20% of lake users come from within a 25 mile radius, 26% from within a 26 to 50 mile radius, and 11% from within a 51 to 75 mile radius. This information highlights the need for the Master Plan to address recreational development best suited to the type of visitor travelling a substantial distance to the lake. TABLE 4 presents a summary of actual visitation from 1958 through 1998.



3. Projected Visitation. A discussion of projected visitation at Wappapello Lake is presented in paragraph 5-14.
   Table 4 WAPPAPELLO LAKE ACTUAL VISITATION DATA 1958 - 1998

   Year	Recreation Use Days (except as noted)	Visitor Hours
   1958	423,590	--
   1959	440,100	--
   1960	476,800	--
   1961	533,500	--
   1962	601,100	--
   1963 *	1,229,890	--
   1964	1,163,770	--
   1965	1,110,450	--
   1966	1,292,380	--
   1967	1,217,720	--
   1968	1,319,560	--
   1969	1,580,640	--
   1970	1,664,980	--
   1971	1,870,770	--
   1972	2,031,450	--
   1973	1,743,820	--
   1974	2,l20,740	--
   1975	1,998,590	--
   1976	1,743,825	--
   1977	1,868,100	--
   1978	1,600,600	--
   1979	2,168,800	--
   1980	1,936,860	--
   1981	1,549,l50	--
   1982	1,974,780	--
   1983	2,038,870	--
   1984	2,101,600	--
   1985	2,106,246	--
   1986	2,094,309	--
   1987	2,084,047	--
   1988	2,304,706	--
   1989	2,237,817	--
   1991•	2,263,199	6,616,751
   1992•	2,215,805	9,044,760
   1993•	2,371,532	13,983,305
   1994†	2,182,090	13,369,196
   1995†	2,300,425	14,018,422
   1996†	2,362,248	14,729,941
   1997†	2,016,356	17,403,759
   1998†	2,017,391	16,596,142

   * Initial year of traffic counter/load factor use
   •VERS Data
   †Visits (No Recreation Use Day data available
   Continue to Section III -- Operating Projects: Status