How to Measure Water Current of Ohio River?

1. Where is Ohio River?

The Ohio River is a really great and significant stream that flows through a big part of America. Its origin comes from Pittsburgh, Pennsylvania, where it arises from the confluence between the Allegheny River and the Monongahela River. It now winds its way southwestward for approximately 981 miles (1,579 kilometers) before emptying into the Mississippi River at Cairo, Illinois.

This river forms a natural boundary between several states. It flows along the southern border of Ohio, giving the state its name. To the south, it forms part of the border between Indiana and Kentucky, further south between Illinois and Kentucky. As it courses its way down the current, it passes through many cities and towns, each with its own charm and history. It is due to its proximity to the Ohio River that Cincinnati, Ohio, and Louisville, Kentucky, have grown into the thriving cities they are today.

Indeed, the Ohio River has had a very significant role in trade, transportation, and the settlement pattern ever since the founding of America. Initially, it served as a major route west for pioneers and was once loaded with barges and steamboats carrying goods and people. Lush forests, fertile farmland, and rolling hills speckle the riverbanks, forming a variegated landscape that has served as inspiration for many artists and writers over the years. The river is not only a geographical feature but also a cultural and historic icon carved into the American Midwest.

2. What is the Flow Rate of the Ohio River Like?

The Ohio River bears a lot of significance in the United States. It facilitates a part of the national inland waterway system through the transportation of large cargo that ranges from coal to grain and manufactured goods. This has contributed greatly to the economy of the regions that it has passed.

In the course of a year, the Ohio River undergoes changes in flow rate and discharge. The flow rate can be as low as about 28,000 cubic feet per second to over 1 million cfs, comparing cases of heavy rainfall or snowmelt. Precipitation events over its watershed-which is very large, partly covering several states-is one of those factors that affect the river's flow.

The discharge of the Ohio River also depends on how the dams and reservoirs within its route are regulated. These may be built for flood control, water supply, or hydroelectric power. For example, the Kentucky Dam on the Tennessee River, a tributary river of the Ohio River, can manipulate the flow in the downstream portions of the Ohio River by controlling the amount of released water.

In general, the Ohio River characterizes quite a complex and dynamic flow that plays an important role in the ecosystem, economic, and social aspects of the regions it touches.

3. How to Measure Water Current of Ohio River?

The traditional approaches for measuring the current of river water will include using current meters. These current meters come in either a mechanical or electrical construction, generally being set out in the water and measuring the speed and direction of flow directly. Other approaches will make use of floats, which are also marked, with timing of their motion on the surface to work out the approximate speed of the current.

Of late, however, ADCP profiler have been being extensively used as a better and more convenient device for the measurement of river currents. Compared to the conventional methods, the following added advantages are offered by the ADCP meter: they are able to provide in one go the water column velocity profile at several depths for more complete coverage of flow characteristic knowledge of the river.

3.1 How Do the ADCPs Based on the Doppler Principle Work?

The working principle of Acoustic Doppler Current Profiler(ADCP) is based on Doppler. Acoustic pulses are transmitted by them into the water and detect echoes reflected back through particles and other objects in the water. If the water is in motion, then due to the Doppler effect, the frequency of reflected echoes would shift. This shift in frequency is the measure with which the ADCP flow meter will be able to find the velocity at different depths.

The traditional device carries several transducers oriented in different directions and measures the horizontal and vertical components of flow. Thus, it enables highly sophisticated three-dimensional mapping of water current, which is very useful for ascertaining flow patterns and possible variations across the water column.

3.2 What's Required to Effect High-Quality Measurement of Currents in Ohio River?

In making quality measurements of the Ohio River currents using ADCP doppler, there is a number of factors concerning the equipment that become quite important. The first and foremost factor is the material used in making the ADCP; these must be reliable. For instance, it should be of importance that the casing of the ADCP is made of a material that is strong enough and, at the same time, light in mass.

For the casing material, titanium alloy will be an excellent choice. Titanium alloy provides a good deal with various benefits. To mention, it has a high strength-to-weight ratio, good enough to bear all types of stress underwater, say in the Ohio River, with minimal weight for handling and deployment of the ADCP current profiler.

It is also highly resistant to corrosion. Because river waters are in general harsh and corrosive, with large amounts of minerals and chemicals, the corrosion resistance of the titanium alloy helps ensure that the ADCP current meter operates reliably over long periods with high accuracy. Thermal stability is good and should be applicable within various water temperature conditions within the Ohio River.

Besides that, for the measurements on a large scale over the Ohio River, it is preferable that an ADCP current has low power consumption and at a low cost. This shall allow for wider ranges of deployments of the devices without energy and financial costs becoming unbearably high. Low-power-consuming ADCP can thus run for longer lengths of time using battery power or with less demanding power supply requirements, and therefore this type shall be more suitable for remote or continuous monitoring applications.

3.3 How to Choose the Right Equipment for Current Measurement?

Selection of proper acoustic doppler velocity meter equipment for the Ohio River is based on various considerations when current measurement is to be conducted. Firstly, the purpose of measurement will determine the type of ADCP to be selected. This would involve a Horizontal Acoustic Doppler Current Profiler if the focus is to be on the horizontal flow across a section of the river. HADCPs were designed to give accurate horizontal velocity components of the water current.

If the intention of measurement is to study the vertical flow profile of the river, a Vertical Acoustic Doppler Current Profiler would be more suitable. VADCPs are configured to measure the velocity of the water along a vertical line in the river at various depths.

Besides the type of acoustic doppler flow meter, another consideration that goes along is the acoustic pulse frequency. Because there are different frequencies depending on the depth of water, one normal frequency is the 600 kHz ADCPs, which are usually good to about 70 meters of water. This frequency has good resolution and accuracy in waters that are not particularly deep. In the case of deeper waters, such as could be encountered with parts of the Ohio River where depth is in excess of 70 meters, a 300 kHz ADCP is often desirable since it better penetrates into the water column and gives reliable measurements up to approximately 110 meters.

On the market now, there are famous brands of ADCPs like Teledyne RDI, Nortek, and Sontek. But for those who need budget-friendly equipment with excellent quality, the best option can be China Sonar PandaADCP. It is produced with all-titanium alloy material, which will guarantee long-time durability and reliability and bring an incredible price-performance ratio. You can learn more about it from their official website: https://china-sonar.com/.

Here is a table with some well known ADCP instrument brands and models.