A History of High Water Levels on Crooked Lake

During this period of heavy rains and high water on Crooked Lake, there is much discussion in our community about how Crooked Lake ought to drain. There exists today a canal between Crooked Lake and Lake Clinch. Across the canal exists a concrete weir. During periods of high lake levels, water can flow through the canal, over the weir to Lake Clinch. However, during a long period of low water on Crooked Lake, from 1961 through 2005, the canal stayed dry and was overgrown by upland vegetation.

The history of the canal and the weir is not well understood, which has led many in our community to make assumptions about its origin and original intention. For example, many assume that it was constructed by a government agency or formal drainage district. Further, many assume that in the years shortly after the canal and weir were constructed Crooked Lake was maintained at or below the lowest elevation of the weir. Based on my review of historical newspapers, court records, and technical publications from various state agencies, it appears that both of those assumptions are incorrect.

The following report summarizes the available historical records regarding water levels and drainage for Crooked Lake. The following conclusions can be drawn from the available records:

The drainage canal between Crooked Lake and Lake Clinch has been privately owned and maintained since the late 1880s.
The first documentation of government involvement in the drainage of Crooked Lake was vegetative maintenance of the canal performed in 2005
Attempts to deepen and widen the canal by the landowners in the 1920s were vigorously opposed by landowners in the Babson Park area, including with a court injunction.
Similar attempts to form a drainage district via the Florida legislature were also opposed
A near-continuous record of water levels for Crooked Lake exists from 1945 through present
Crooked Lake has been at or above the weir elevation 5 times since 1945
Current flow rates through the canal are comparable to the flow rates from the 1940s-50s

The Southwest Florida Water Management District (SWFWMD) recently evaluated Crooked Lake for the establishment of its minimum flow and level (MFL). This is a thorough analysis that includes considerations for recreation, fish and wildlife habitat, aesthetic and scenic attributes, water quality and navigation. Because of the variability in water levels, the MFL is expressed as a percentage with two components:

A High Minimum Lake Level is the elevation that a lake’s water levels are required to equal or exceed ten percent of the time on a long-term basis.
A Minimum Lake Level that is the elevation that the lake’s water levels are required to equal or exceed fifty percent of the time on a long-term basis.

The High Minimum Lake Level established for Crooked Lake is approximately 0.7 feet above the lowest elevation on the weir in the drainage canal.¹

The historical record and the recent MFL evaluation indicate that the current high lake levels on Crooked Lake are not uncommon and are a necessary part of maintaining a healthy lake.

Attempts to Drain Crooked Lake

In 1881, Hamilton Disston signed a Contract with the Florida Inland Improvement Trust that allowed him to drain submerged lands south of present-day Kissimmee and east of the Peace Creek.²

In an 1893 report to the Florida Legislature summarizing the drainage activities of the Disston Land Company, it was noted that “a canal was also constructed from Lochappopka Lake to Crooked Lake.”³ Lochappopka is the old name for Lake Clinch, as shown on an 1883 sectional map of Polk County.⁴

Stephen W. Carson moved his family from Fort Meade to a homestead near the southern end of Crooked Lake.⁵ According to a letter that Mr. Carson penned to The Florida Agriculturist in 1890, he had started work on a drainage canal around this time. From Mr. Carson:

As to the drainage of Crooked lake, it proved to be ineffectual in carrying off the large collection of water through the rainy season, and work had to be renewed on it. Mr. Keller, the surveyor, constructed a log dredge, which was put in near the head of the canal and for ten or twelve days I have had charge of hands working it and it has done more in moving sand, muck and hard pan than 100 hands could have done with ordinary fools in the same length of time.⁶

Between the 1890s and the 1920s, the town of “Crooked Lake” began to develop near the northeastern corner of the lake with land purchases by the Cody, Fairchild, Yarnell, and Babson families, among others.

In 1922, J.W. Carson (descendent of S. W. Carson) and J.B. Corlett deepened and widened the canal with the intent of improving their lands along the southern and western ends of the lake. Locals estimated that approximately 2 feet of water was flowing through the ditch at a rate of 10,000 gallons per minute (22 cubic feet per second (cfs)). A group of residents from the Crooked Lake townsite (soon to be renamed Babson Park) filled in the ditch for a considerable distance. The town residents, including H. E. Fairchild and F. J. Keiser also filed a court injunction to prevent the lake to be lowered.⁷

In July 1923, the attorney for J.W. Carson gave notice to the court asking for the injunction to be dissolved. Judge Edwards visited the lake before making his decision. He visited Babson Park and was scheduled to visit the canal but was prevented from doing so by engine trouble on the boat he was to use.⁸

In August 1923, Judge Edwards requested a surveyors report on the Lake, indicating a court decision was not imminent.⁹

In October 1925, three local residents proposed the creation of a drainage district that would encompass Crooked Lake. They proposed to submit the drainage district to the Florida Legislative Session of November 1925 and scheduled a town meeting to solicit input.¹⁰ At the town meeting on October 27, 1925, the overwhelming majority of residents opposed the formation of the drainage district.¹¹ A review of the legislative session records from November 1925 indicate that no such drainage district was put forward.

In 1959, the Florida Legislature created the Peace River Valley Water Conservation and Drainage District. In November 1960, the district prepared a report detailing proposed projects throughout the Peace River watershed. The report also proposed a project to make improvements to the canal between Crooked Lake and Lake Clinch. The estimated cost of all the projects described in the report was approximately $40,000,000. However, the legislature only gave the district the ability to levy approximatley $200,000 annually.¹² Further, when SWFWMD was created in 1961, the legislature directed that the Peace River Valley Water Conservation and Drainage District would be absorbed by SWFWMD in June 1963. In 1961, the Peace River Valley Water Conservation and Drainage District set a 2-year budget of $400,000 and focused on their high-priority projects, which did not include Crooked Lake.¹³ Curiously, when the Peace River Valley Water Conservation and Drainage District was dissolved, Crooked Lake and Lake Clinch were not included in the boundary of SWFWMD. They were also outside the boundaries of the Central and Southern Flood Control Project, which eventually became the boundaries of the South Florida Water Management District.¹⁴ It was not until 1972 when the legislature modified the boundary of SWFWMD to include Crooked Lake and Lake Clinch.¹⁵

In 1961, the Florida Geological Survey (FGS) described the Crooked-Clinch canal as follows:

The discharge from Crooked Lake to Lake Clinch has been controlled by the installation of two concrete controls at different times, and by an earthfill placed in the canal near Crooked Lake.¹⁶

This statement from the FGS indicates that the flow through the canal was not strictly controlled by the weir elevation and other factors (e.g. earthfill in the canal) also limited flow out of Crooked Lake.

Crooked Lake Water Levels

A note on vertical datum: When comparing elevations it is critical to maintain a consistent vertical datum. Unfortunately, since the historical record for this report begins in the 1880s, it’s not possible to confirm the vertical datum that was being used for many of the earlier records. In the early 20th century, many government agencies started using the National Geodetic Vertical Datum of 1929 (NGVD29). In recent years, state and federal agencies have adopted the North American Vertical Datum of 1988 (NAVD88). The difference between NGVD29 and NAVD88 varies across the country. In the Crooked Lake area, NGVD29 is approximately 1 foot higher than NAVD88. To maintain consistency for this report, all elevations described below are referenced to NAVD88. Historical references to elevations in NGVD29 or “mean sea level” have been adjusted to NAVD88. For example, if a historical document described an elevation as 120 feet mean sea level, I describe it below as 119 feet NAVD88.

Water levels on Crooked Lake have been recorded at least monthly since 1945. A graph of water levels since 1945 is presented in the figure below.

In the summer of 2019, the gauge at Bob’s Landing peaked at approximately 120.89 feet NAVD88 at the end of August. Based on the available data, Crooked Lake has been at or above current water levels 5 times since 1945:

late 1945 – early 1946
late 1947 – early 1950
late 1953 – early 1955
late 1959 – early 1961
early 2005 – early 2006

The earliest reference to a water elevation for Crooked Lake comes from a survey taken in 1881 that states the lake was 132 feet above the high water mark in Charlotte Harbor.¹⁷ This same elevation is noted in the legislative report on the Disston drainage company and the Polk County sectional map of 1893. Newspaper accounts from 1923 described recent surveys indicating the lake was at 127 feet NAVD88.¹⁸

The following is excerpted from a 1973 study of biological indicators of high water elevations on Crooked Lake:

The levels of this lake have been raised and lowered by a canal, and have varied from [117 to 121 feet NAVD88] with some stages up to [123 feet] after 1945. The berm ridge is some-what higher than [123 feet]. Landward from this berm ridge are located a few black gum trees with distinct buttressed bases which indicate that they were surrounded by 2-3 feet of water for a number of years. One of these trees was cut and sectioned, which had 55 growth rings. This indicates that water was a few feet deep here back to 1918 or earlier. This means that water flooded up to [125.5 feet NAVD88], and probably 2-3 ft. higher, during a few years after 1918, or for the number of years required to develop the buttressed bases on the black gum trees. However, the gum trees are in a swale, and their growth period may not have been connected with the lake. If so, they do not indicate a former lake level. A grove of live oaks, farther inland than the gum trees, on soils above [129 feet NAVD88] indicates that the lake water probably did not exceed this elevation for the time of the age of these trees, which is estimated at about 75 years, or back to before 1900.¹⁹

This biological study indicates that high water levels in the 1920s were likely higher than they are today, especially before Mr. Carson expanded and deepened the canal. However, it seems unlikely that water levels ever reached as high as was noted in the 1881 survey.

Crooked-Clinch Canal Flow Rates

The earliest estimate of flow rate through the canal was by local residents in 1922, after Mr. Carson expanded and deepened the Canal. They estimated that approximately 2 feet of water was flowing through the ditch at a rate of 10,000 gallons per minute (22 cfs).²⁰

Starting in 1947, the United States Geological Survey began periodic measurements of the flow rate through the canal. Flow rate data is available on their website from 1947 through 1959.²¹ The flow ranged from 0 up to 66 cfs, which was recorded in September of 1948. Measurements were taken where the canal passes under CR 630A through a culvert.

During the Summer of 2019, Polk County Road & Drainage Division replaced the culvert. The new structure is approximately 8 feet wide.

From August 22nd-25th, staff from Polk County Road & Drainage removed vegetation from the canal from CR 630 north towards Little Crooked Lake. In September 2019, staff from SWFWMD began measuring flow rates through the canal.

The Relationship Between Lake Levels and Flow Through the Discharge Canal

Under certain circumstances, the maximum elevation of lakes can be controlled very closely to the minimum elevation of the control structure for that lake. This is particularly true with small water bodies that have relatively large control structures. However, Crooked Lake is a large waterbody with a relatively small discharge canal.

Within the canal is a concrete structure with two rectangular weirs, each approximately 4 feet wide. The bottom elevation of the weirs is approximately 119 feet NAVD88.

A recent photo of the weir is shown here (taken on August 23, 2019 while Polk County Roads & Drainage staff were performing vegetative maintenance on the canal. Courtesy of Lisa Jensen).

In a flowing channel, several factors can contribute friction thereby reducing the flow rate and causing the water body to stage up above the weir elevation, such as:

The roughness of the canal bottom and sides
The relatively shallow gradient of the canal
Vegetation growth in the canal channel

The distance from open water on Crooked Lake to open water on Lake Clinch is approximately 6,700 feet. The vertical elevation change is approximately 15 feet. However, the section north of CR 630A is relatively flat and nearly all the elevation change occurs Between CR 630A and Lake Clinch.

The profile of the canal.

The flow through the canal was measured by the USGS from 1947 through 1959, and then again by SWFWMD in 2019. A graph of flow rates compared to Crooked Lake levels is shown in the following figure.

From 1961 through 2005, Crooked Lake was low enough that the canal remained dry. The interceding 44 years between discharges was long enough for a well defined channel to evolve into a heavily vegetated slough. A comparison of 1941 and 2002 aerial imagery of this location is shown below.

Interestingly, even when most of the canal was well defined in the 1940s, Crooked Lake still staged above the weir. This indicates that a combination of factors contribute to Crooked Lake staging above the weir.

Attempts to Drain Crooked Lake

Crooked Lake Water Levels

Crooked-Clinch Canal Flow Rates

The Relationship Between Lake Levels and Flow Through the Discharge Canal

References