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Jonathan K. Lee

Publications and source records attributed to Jonathan K. Lee.

7 recordsLinked to original sources
USGS2000

Sawgrass density, biomass, and leaf area index: A flume study in support of research on wind sheltering effects in the Florida Everglades

The U.S. Geological Survey is studying the wind sheltering effects of vegetation in the Florida Everglades. In order to test both the flow resistance and wind sheltering effects of sawgrass, uniform dense stands of sawgrass were grown in a tilting flume at Stennis Space Center, Mississippi. In June, 1997, one end of the flume was covered with a wind cowling with a removable top, and a series of experiments were conducted between June, 1997 and July, 1998. During each set of experiments, the sawgrass was sampled for vegetative characteristics, biomass, and leaf area index. The results of the analyses of the vegetation samples are summarized in a series of appendixes.

Florida↗
USGS2000

Velocity and stage data collected in a laboratory flume for water-surface slope determination using a pipe manometer

U.S. Geological Survey (USGS) hydrologists and ecologist are conducting studies to quantify vegetative flow resistance in order to improve numerical models of surface-water flow in the Florida Everglades. Water-surface slope is perhaps the most difficult of the flow resistance parameters to measure in the Everglades due to the very low gradients of the topography and flow. In an effort to measure these very small slopes, a unique pipe manometer was developed for the local measurement of water-surface slopes on the order of 1 centimeter per kilometer (cm/km). According to theory, a very precise measurement of centerline velocity obtained inside the pipe manometer should serve as a unique proxy for water-surface slope in the direction of the pipe axis. In order to confirm this theoretical relationship and calibrate the pipe manometer, water-surface elevation and pipe centerline velocity data were simultaneously measured in a set of experiments carried out in the tilting flume at the USGS Hydraulic Laboratory Facility at Stennis Space Center, Mississippi. A description of the instrumentation and methods used to evaluate this technique for measuring water-surface slope as well as a summary of the entire data set is presented.

Open-File Report↗
USGS1999

Vegetative resistance to flow in south Florida: Summary of vegetation sampling at sites NESRS3 and P33, Shark River Slough, November, 1996

The U.S. Geological Survey is one of many agencies participating in the effort to restore the South Florida Everglades. We are sampling and characterizing the vegetation at selected sites in the Everglades as part of a study to quantify vegetative flow resistance. The objectives of the vegetation sampling are (1) to provide detailed information on species composition, vegetation characteristics, vegetation structure, and biomass for quantification of vegetative resistance to flow, and (2) to use this information to classify the vegetation and to improve existing vegetation maps for use with numerical models of surface-water flow. Vegetation was sampled at two sites in the Shark River Slough in November, 1996. The data collected and presented here include those for live and dead standing sawgrass, other dead material, periphyton biomass, vegetation characteristics and structure, and leaf area index.

Florida↗
USGS1999

Biomass and vegetative characteristics of sawgrass grown in a tilting flume as part of a study of vegetative resistance to flow

The U.S. Geological Survey is studying vegetative resistance to flow in the south Florida Everglades as part of a multidisciplinary effort to restore the South Florida Ecosystem. In order to test the flow resistance of sawgrass, one of the dominant species in the Everglades, uniform, dense stands of sawgrass were grown in a tilting flume at Stennis Space Center, Mississippi. Depth of water in the flume was controlled by adding or removing metal plates at the downstream end of the flume. A series of experiments were conducted at various flow depths, and the velocity, flow depth, and water-surface slope were measured. During each set of experiments, the sawgrass was sampled in layers from the sediment water interface for vegetative characteristics, biomass, and leaf area index. The results of the vegetation sampling are summarized in a series of tables.

Open-File Report↗
USGS1994

Simulating effects of highway embankments on estuarine circulation

A two‐dimensional, depth‐averaged, finite‐difference, numerical model was used to simulate tidal circulation and mass transport in the Port Royal Sound, South Carolina, estuarine system. The purpose of the study was to demonstrate the utility of the Surface‐Water, Integrated, Flow and Transport model (SWIFT2D) for evaluating changes in circulation patterns and mass transport caused by highway‐crossing embankments. A model of a subregion of Port Royal Sound including the highway crossings and having a grid size of 61 m (200 ft) was derived from a 183‐m (600‐ft) model of the entire Port Royal Sound estuarine system. The 183‐m model was used to compute boundary‐value data for the 61‐m submodel, which was then used to simulate flow conditions with and without the highway embankments in place. The numerical simulations show that, with the highway embankments in place, mass transport between the Broad River and Battery Creek is reduced and mass transport between the Beaufort River and Battery Creek is increased. The net result is that mass transport into and out of upper Battery Creek is reduced. The presence of the embankments also alters circulation patterns within Battery Creek.

Journal of Waterway, Port, Coastal and Ocean Engin↗
USGS1988

Analysis of alternative modifications for reducing backwater at the Interstate Highway 10 crossing of the Pearl River near Slidell, Louisiana

In April 1979 and April 1980, major flooding along the lower Pearl River caused extensive damage to homes located on the flood plain in the Slidell, Louisiana, area. In response to questions about causes of these floods and means of mitigating future floods, the U.S. Geological Survey, in cooperation with the Louisiana Department of Transportation and Development, Office of Highways, and the U.S. Department of Transportation, Federal Highway Administration, used a two-dimensional finite-element surface-water flow-modeling system to study the effect of four alternative modifications for improving the hydraulic characteristics of the Interstate Highway 10 crossing of the flood plain near Slidell. The analysis used the model's capability to simulate changes in flood-plain topography, flood-plain vegetative cover, and highway-embankment geometry. Compared with the existing highway crossing, the four alternative modifications reduce backwater and average velocities through bridge openings for a flood of the magnitude of the 1980 flood. The four alternatives also eliminate roadway overtopping during such a flood. For the four modifications, maximum backwater on the west side of the flood plain ranges from 0.3 to 1.1 feet and on the east side from 0.3 to 0.7 foot. Results of the alternative-model simulations show that backwater is greater on the west side of the flood plain than on the east side, but upstream from Interstate Highway 10 backwater decreases more rapidly in the upstream direction on the west side of the flood plain than on the east side. Downstream from Interstate Highway 10, modeling of the four alternatives indicates that backwater and drawdown still occur on the east and west sides of the flood plain, respectively, but are less than the values computed for the April 1980 flood with Interstate Highway 10 in place. In addition to other highway-crossing modifications, alternatives 2 and 3 include simulation of a new 2,000-foot bridge opening, and ,alternative 4 includes simulation of a 1,000-foot bridge opening. The new bridge conveys 25, 23, and 21 percent of the total computed discharge in alternatives 2, 3, and 4, respectively. The average velocity through the new bridge is 2.0, 1.9, and 3.4 feet per second for alternatives 2, 3, and 4, respectively.

Water Supply Paper↗