Lakes and Special Studies

 

"Bathymetric mapping" is a technical term for mapping lake-bottom contours. The OWRB's current bathymetric mapping program utilizing GIS and related technologies began in the late 1990s. Its purpose was to develop a tool that could be used to provide accurate determinations of the current storage capacities in the state’s reservoirs. Obtaining accurate storage volumes is an integral tool used in the management of the state’s water supply. For many reservoirs, the only available storage volumes are those that were estimated when the reservoir was first constructed. Because of sediment deposition that occurs in the reservoir, the volume of the reservoir can be reduced over time. By conducting a bathymetric survey, the managing authority of a reservoir can be better equipped to handle critical water management issues.

The process of surveying a reservoir uses a combination of Geographic Positioning System (GPS) and acoustic depth sounding technologies that are incorporated into a hydrographic survey the vessel. The OWRB uses an 18-ft aluminum hull Silverstreak craft with a cabin, powered by a single 115-Horsepower Mercury outboard motor. The equipment used to conduct the survey include: a ruggedized notebook computer, an Syqwest Bathy 1500 Echo Sounder, a Trimble Navigation, Inc. Pro XR GPS receiver with differential global positioning system (DGPS) correction, and a Odom Hydrographics, Inc, DIGIBAR-Pro Profiling Sound Velocimeter. As the survey vessel travels across the lake’s surface on pre-plotted transect lines, the echo sounder gathers approximately eight readings per second from the lake bottom. The depth readings are stored on the survey vessel’s on-board computer along with the positional data generated from the vessel’s GPS receiver. Accurate estimates of area-capacity can be determined for the lake by building a 3-D triangulated irregular network (TIN) model of the reservoir from the collected data.

Bathymetric maps available for download on our Web site include the following:

Oklahoma reservoirs are sadly missing aquatic vegetation on their shorelines. What is aquatic vegetation and why is this important? Aquatic vegetation refers to plants that can live in permanently saturated soils. Some may be emergent leaved plants such as bulrush, some are floating leaved plants like water lilies. Others are completely submersed plants like water stargrass or valisneria. Aquatic plants work as a buffer to the shoreline. They can be a natural and more attractive "rip-rap" with other benefits.

• Their roots systems protect the shallow sediment from resuspension by waves. The above ground plants dissipate the wave energy that would otherwise erode the bank.
• Aquatic plants take up nutrients out of the water column reducing algal biomass, add dissolved oxygen, and increase water clarity. Some plants take up and bind contaminants such as heavy metals in the water column.
• Another important reason to have vegetated shorelines is they act as wetland habitat for many species of wildlife including birds, fish, and turtles. Young of the year fish as well as their predators use these plants for cover.
• Plants give our shorelines a natural more aesthetic look than the typical bare red dirt and sandstone banks that we see all too often around our state.
• Getting beneficial native plants in our reservoirs protects them from possible (perhaps we should say "probable") future infestations of unwanted nuissance or exotic plant species that inevitibly find their way to an open niche. We hope to get desirable plants established in our lakes first.

To get these wetlands started in a lake OWRB plants potted plants with well established root systems in shallow coves. Then we cage the plants to protect them from turtles, carp and other herbivores. These plantings are called "founder colonies". Over time, these plantings will spread by rhizome, fragments and seed to populate the cove sufficiently to overcome the herbivory pressure and thus no longer need the cages or pens to survive and multiply. This will take several years to establish but once in they take hold their spread will be exponential. The positive changes to that littoral (shallow shoreline of the lake) ecosytem will be measurable and significant.

The Lakes and Special Studies section along with other partners, such as GRDA and ODWC, have been planting Grand, Wister, Atoka and Stanley Draper Lakes and has worked limited plantings in Lake Carl Blackwell and Thunderbird. With other proposals on the drawing board we are constantly searching for funding sources to continue this work across the state. The OWRB and our partners cannot possibly plant every lake in the state. Our hope is that as successes develop lake managers across our state will see its advantages and want to enhance their shorelines as well.

Other types of restoration can be accomplished through shoreline erosion control projects such as those done in Lake Carl Blackwell and Lake Thunderbird or through new technologies such as floating wetlands or pumping super-oxygenated water into a lake to prevent summertime anoxia (see current studies).

Reports of finalized projects can be found on our Technical Reports page.

Thunderbird Lake Diagnostics - Supported by the Central Oklahoma Master Conservancy District (COMCD), the OWRB has monitored water quality at Lake Thunderbird since 2000. From this a long-term water quality database that has been established which has allowed the OWRB to characterize lake nutrient dynamics and make recommendations to target a reduction of the lake’s problems due to excessive algae growth. Current work includes sampling chlorophyll and nutrient concentrations; the source of several impairments in the lake.

Revegetation Plantings of Lake Atoka - Final Report just released - OWRB and Oklahoma City with 104(b)(3) Wetlands Grant from EPA is introduced aquatic plants to Atoka Lake. While the primary goal was to increase wetland acreage in the watershed, erosion control and improved water quality are additional benefits gained from this project. With the use of plastic coated wire, over 200 cages and pens have been built at 5 sites around the lake to provide long term protection from carp, turtles and other herbivores in the lake. These cages of plants termed "founder colonies" have been planted with 25 native species of aquatic emergent and submergent plants beneficial to fish and waterfowl. These long term founder colonies will stay in place for several years sending out seeds and fragments slowly but surely populating the lake. Once established these plants will protect the shorelines of these and other coves around the lake from wave action and actually trap sediment being washed in from surface runoff.

Identification of the State's "Oxbow Lakes" - With funding from EPA Region 6, and in partnership with the Oklahoma Conservation Commission and Oklahoma State University we are looking at part of our wetland ecosytem that is largely unknown. The project is focused on locating, quantifying and characterizing the population of oxbow lakes found in Oklahoma to determine their "Use Attainability". Level 1 assessments have been developed thus far that may eventually become a methodology for rapid assessments of these and other wetland types. Level 2 and 3 assessments are forthcoming.

Prevention of Anoxic Hypolimnion in Lake Thunderbird - In 2010, the COMCD partnered with the OWRB, to design, install, and monitor a SDOX pump at the lake’s deepest area near the dam. This energy-efficient pump uses the latest technology to prevent the lakes hypolimnion from going anoxic throughout the summer months without disrupting the lake’s natural thermocline. The pump essentially mixes water that has been supersaturated with dissolved oxygen to approxiamtely 300%. It has been determined that the seasonal anoxia that occurs each summer, is changing the lakes chemistry in a way that it exacerbates the eutrophic condition. Implementation of the SDOX device is targeted to not only improve water quality in the lake for biota but also to reduce the cost to treat as a drinking water source. Lake Thunderbird water is treated by the cities of Norman, Del City and Midwest City for potable water supply. Funding for this effort was obtained through the American Recovery and Reinvestment Act of 2009.

In 2007, the Oklahoma Water Resources Board participated in the National Lakes Survey by sampling thirty-five probabilistic sites. Headquarter 106 monies were leveraged with regional funds for eighteen additional sites allowing a state level survey. The bulk of the entire probabilistic survey included Beneficial Use Monitoring Program lakes (30/53). The Environmental Protection Agency provided many beneficial facets for participating in the survey. One of the key areas was building capacity for improving the monitoring program at the state level. Because the majority of lakes that were sampled by the probabilistic survey were BUMP lakes, the demonstration allowed for long-term BUMP monitoring data to be compared to the data from the survey, an inventory of the lakes within the twelve ecoregions of the state, and biological parameters and data to be added to the assessment of the states waters. Oklahoma is looking to the future with the possibility of using the data for further development of nutrient and biological criteria, re-evaluating the water quality standards for these waters and incorporating new parameters into the established monitoring program.