Flow rate determination based on limited observations

Methods, systems and computer program products for determining an accurate flow rate based on limited observations are provided. Aspects include receiving a limited sample of flow rate data associated with a test site of a test river. Aspects also include determining topographical characteristics of the test site. Aspects also include determining a plurality of similar tested sites and generating a test site rating curve based on a combination of the limited sample of flow rate data and sufficient flow rate data associated with one or more of the plurality of similar tested sites. Aspects also include obtaining a stage reading associated with the test site from a sensor disposed at the test site. Aspects also include determining a flow rate of the test site based on the stage reading and the test site rating curve.

BACKGROUND

The present invention generally relates to programmable computing systems, and more specifically, to computing systems, computer-implemented methods, and computer program products configured to determine an accurate flow rate (e.g., of a river stream) based on limited observations.

A flow rate of a river stream is a representation of the volume of liquid per second that is flowing through a given point of a river. River stream flow rates can be a crucial hydrologic variable that can impact flooding and the operation of river-based sites such as dams, floodgates, hydroelectric power facilities and the like. River stream flow rates can vary at different points along the same river due to the topography of the river and can also vary over time due to variable water levels (e.g., due to irregular rainfall patterns). A river stream flow rate for a particular point of a river can be determined by directly measuring the flow of the river at that point, but this is typically difficult and expensive as it requires specially constructed weirs and flow velocity measurement instruments. A rating curve for a particular point in a river can be extrapolated to provide a flow rate for the point in the river as a function of the stage (i.e., water level) of the river based on a plurality of measurements taken at the point in the river at different stages. Such rating curves are site specific and requires many data points spanning across various flow conditions, which can be very time and labor intensive to acquire.

SUMMARY

Embodiments of the present invention are directed to a computer-implemented method for determining an accurate river stream flow rate based on limited observations. A non-limiting example of the computer-implemented method includes receiving a limited sample of flow rate data associated with a test site of a test river by a processor. The limited sample of flow rate data may include a number of data points that is less than a threshold number of data points. The method also includes determining topographical characteristics of the test site by the processor. The method also includes determining a plurality of similar tested sites by the processor. A similar tested site can include a river site having topographical characteristics that are above a threshold level of similarity to the topographical characteristics of the test site and about which sufficient flow rate data has been collected for generating an accurate rating curve. Sufficient flow rate data may include a number of data points that is greater than or equal to the threshold number of data points. The method also includes generating a test site rating curve by the processor based on a combination of the limited sample of flow rate data and the sufficient flow rate data of one or more of the plurality of similar tested sites. The method also includes obtaining a stage reading associated with the test site from a sensor disposed at the test site. The method also includes determining a flow rate of the test site by the processor based on the stage reading and the test site rating curve.

Embodiments of the present invention are directed to a system for determining an accurate river stream flow rate based on limited observations. The system includes a memory having computer readable computer instructions, and a processor for executing the computer readable instructions. The computer readable instructions include instructions for receiving a limited sample of flow rate data associated with a test site of a test river. The limited sample of flow rate data may include a number of data points that is less than a threshold number of data points. The computer readable instructions also include instructions for determining topographical characteristics of the test site. The computer readable instructions also include instructions for determining a plurality of similar tested sites. A similar tested site can include a river site having topographical characteristics that are above a threshold level of similarity to the topographical characteristics of the test site and about which sufficient flow rate data has been collected for generating an accurate rating curve. Sufficient flow rate data may include a number of data points that is greater than or equal to the threshold number of data points. The computer readable instructions also include instructions for generating a test site rating curve based on a combination of the limited sample of flow rate data and the sufficient flow rate data of one or more of the plurality of similar tested sites. The computer readable instructions also include instructions for obtaining a stage reading associated with the test site from a sensor disposed at the test site. The computer readable instructions also include instructions for determining a flow rate of the test site based on the stage reading and the test site rating curve.

Embodiments of the invention are directed to a computer program product for determining an accurate river stream flow rate based on limited observations, the computer program product comprising a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processor to cause the processor to perform a method. A non-limiting example of the method includes receiving a limited sample of flow rate data associated with a test site of a test river. The limited sample of flow rate data may include a number of data points that is less than a threshold number of data points. The method also includes determining topographical characteristics of the test site. The method also includes determining a plurality of similar tested sites. A similar tested site can include a river site having topographical characteristics that are above a threshold level of similarity to the topographical characteristics of the test site and about which sufficient flow rate data has been collected for generating an accurate rating curve. Sufficient flow rate data may include a number of data points that is greater than or equal to the threshold number of data points. The method also includes generating a test site rating curve based on a combination of the limited sample of flow rate data and the sufficient flow rate data of one or more of the plurality of similar tested sites. The method also includes obtaining a stage reading associated with the test site from a sensor disposed at the test site. The method also includes determining a flow rate of the test site based on the stage reading and the test site rating curve.

DETAILED DESCRIPTION

Characteristics are as follows:

Deployment Models are as follows:

Hardware and software layer60includes hardware and software components. Examples of hardware components include: mainframes61; RISC (Reduced Instruction Set Computer) architecture based servers62; servers63; blade servers64; storage devices65; and networks and networking components66. In some embodiments of the invention, software components include network application server software67and database software68.

Workloads layer90provides examples of functionality for which the cloud computing environment may be utilized. Examples of workloads and functions which may be provided from this layer include: mapping and navigation91; software development and lifecycle management92; virtual classroom education delivery93; data analytics processing94; transaction processing95; and determining an accurate river stream flow rate based on limited observations96.

Referring toFIG. 3, there is shown an embodiment of a processing system300for implementing the teachings herein. In this embodiment of the invention, the system300has one or more central processing units (processors)21a,21b,21c, etc. (collectively or generically referred to as processor(s)21). In one or more embodiments of the invention, each processor21can include a reduced instruction set computer (RISC) microprocessor. Processors21are coupled to system memory34and various other components via a system bus33. Read only memory (ROM)22is coupled to the system bus33and can include a basic input/output system (BIOS), which controls certain basic functions of system300.

FIG. 3further depicts an input/output (I/O) adapter27and a network adapter26coupled to the system bus33. I/O adapter27can be a small computer system interface (SCSI) adapter that communicates with a hard disk23and/or tape storage drive25or any other similar component. I/O adapter27, hard disk23, and tape storage device25are collectively referred to herein as mass storage24. Operating system40for execution on the processing system300can be stored in mass storage24. A network adapter26interconnects bus33with an outside network36enabling data processing system300to communicate with other such systems. A screen (e.g., a display monitor)35is connected to system bus33by display adaptor32, which can include a graphics adapter to improve the performance of graphics intensive applications and a video controller. In one embodiment of the invention, adapters27,26, and32can be connected to one or more I/O busses that are connected to system bus33via an intermediate bus bridge (not shown). Suitable I/O buses for connecting peripheral devices such as hard disk controllers, network adapters, and graphics adapters typically include common protocols, such as the Peripheral Component Interconnect (PCI). Additional input/output devices are shown as connected to system bus33via user interface adapter28and display adapter32. A keyboard29, mouse30, and speaker31all interconnected to bus33via user interface adapter28, which can include, for example, a Super I/O chip integrating multiple device adapters into a single integrated circuit.

Thus, as configured inFIG. 3, the system300includes processing capability in the form of processors21, storage capability including system memory34and mass storage24, input means such as keyboard29and mouse30, and output capability including speaker31and display35. In one embodiment of the invention, a portion of system memory34and mass storage24collectively store an operating system coordinate the functions of the various components shown inFIG. 3.

In exemplary embodiments of the invention, a system for determining an accurate river stream flow rate based on limited observations is provided. As discussed above, river stream flow rates can be crucial to making predictions about flooding or other hydrological events that can impact communities or river-based sites such as bridges, dams, hydroelectric power facilities and the like. Conventionally, a rating curve can be used to estimate the river stream flow rate at a river site based on a measurement of the stage of the river. Such rating curves can be extrapolated from measurements at the river site. However, to generate an accurate rating curve, a large number of measurements taken under different conditions are generally needed, which typically requires engineers to physically visit the site and take measurements in visits in multiple seasons (e.g., a rainy season, a dry season, etc.). This process can take a very long time and the resultant river stream flow rate rating curve is only applicable to the specific site at which the measurements were obtained. Further, typical instruments used for measuring flow rate of a river can require 2-3 meters of depth to obtain readings, and thus measurement of very low depths (i.e., depths less than 3 meters) can be difficult or unavailable. If insufficient observations are used to create a rating curve, there is a high likelihood that the rating curve will be of low quality and will produce inaccurate flow rate estimations that can include negative flows and flow rate values with large uncertainties. Thus, traditionally, if an accurate river stream flow rate rating curve is desired for a new site on a river, a site on the river that has had topographical changes that will affect flow rates, or a new river entirely, it is generally necessary to repeat the lengthy and costly process of having engineers visit the site and obtain measurements for months, if not years. However, in exemplary embodiments of the invention, it is possible to provide accurate river stream flow rate predictions for a river site in which relatively few observations and measurements have been made, allowing for an accurate rating curve to be generated significantly faster and with less manual effort by engineers.

According to exemplary embodiments of the invention, the system is configured to allow for the generation of a rating curve for a test river site in which a small number of data points (i.e., observations of river stage and river flow) have been obtained by determining the topographical characteristics of the test river site, identifying river sites with similar topographical characteristics that have been previously tested (i.e., observations have been obtained at the site) and have a relatively large amount of data points, and generating a rating curve based on a combination of data points from the test river and the similar rivers. Thus, embodiments of the invention allow for the creation of an accurate rating curve for a river site in which a limited number of flow rate and stage observations have been made by constructing the rating curve based on a cohort of similar rivers/rivers sites. Once the rating curve for the test river site has been created, the river stream flow rate can be obtained by obtaining a stage reading from the test river site and determining a river stream flow rate of the rating curve that corresponds to the measured stage reading. According to some embodiments of the invention, such stage readings can be obtained remotely, by for example, accessing a stage sensing device (e.g., a radar measurement device) positioned at the test river site that can measure the stage of the river. As will be appreciated, once the river stream flow rate at a particular site on the river is known, it can be used to determine downstream effects, such as when flooding is expected to occur downstream, how fast a reservoir will fill up, when water will spill over a bank of the river and other such predictions. Thus, in response to determining that the river stream flow rate of the test site exceeds or fails to meet a predetermined threshold, the system can issue warnings (e.g., flood warnings) to areas that are projected to be affected or cause anticipatory actions to be taken at river-based sites such as dams, floodgates, hydroelectric power facilities and the like.

Turning now toFIG. 4, a system400for determining an accurate river stream flow rate based on limited observations will now be described in accordance with an embodiment of the invention. The system400includes a river flow rate server410in communication with a stage sensor420and optionally, one or more downstream devices430via communications network415. The communications network415can be one or more of, or a combination of, public (e.g., Internet), private (e.g., local area network, wide area network, virtual private network), and can include wireless and wireline transmission systems (e.g., satellite, cellular network, terrestrial networks, etc.). The various components, modules, engines, etc. described regardingFIG. 4can be implemented as instructions stored on a computer-readable storage medium, as hardware modules, as special-purpose hardware (e.g., application specific hardware, application specific integrated circuits (ASICs), application specific special processors (ASSPs), field programmable gate arrays (FPGAs), as embedded controllers, hardwired circuitry, etc.), or as some combination or combinations of these. According to aspects of the present disclosure, the engine(s) described herein can be a combination of hardware and programming. The programming can be processor executable instructions stored on a tangible memory, and the hardware can include the processing device411for executing those instructions. Thus a system memory (e.g., memory412) can store program instructions that when executed by the processing device411implement the engines described herein. Other engines can also be utilized to include other features and functionality described in other examples herein.

River flow rate server410can include memory that stores data relating to a plurality of river sites, such as observations and measurements about flow rates and stages at the river site and topographical characteristics of the river site, the associated river and/or an area surrounding the river site. A river site can refer to a limited area, portion or span of a portion of a river. For example, the terms “river site” as used herein refers to some or all of an area of a river that is disposed between a few feet along the bank of the river and the corresponding few feet on the opposing bank of the river. Measurements of flow rates and stages from one or more river sites can be user-input into river flow rate server410or can be received (e.g., via wireless communication via network415) from one or more measurement devices, such as for example, stage sensor420. River flow rates (i.e., the volume of fluid which passes per unit time) can be derived from a measured flow velocity combined with a known cross-sectional area of the river at the point of flow velocity (i.e., speed and direction of flow) measurement. Point “flowmeters” can measure the flow at one point in the river or an acoustic Doppler current profiler (ADCP) can measure the two-dimensional cross-sectional flow velocities of a river site. While it is possible to deploy flow velocity instruments at the same location as a stage sensor, it is generally not practical to do so as flow velocity instruments tend to be very expensive. Therefore it is desirable to have a system that can determine the flow rate of a river site based on data collected by a much less expensive stage sensor. Topographical characteristics can include for example but not limited to, a slope of a river bed, a cross-sectional width of the river at the river site and/or other sites of the river, a distance to a downstream lake or reservoir, types of vegetation that are present at the river site and/or along the river, geological features of the river site and/or other sites of the river, detailed cross sectional descriptions, and any other such characteristics of the river site, river or surrounding area that can be useful in characterizing the river flow properties of the river and/or river site. According to some embodiments of the invention, such topographical characteristics can be user-input into river flow rate server based on observations made by engineers in the field, obtained through light detection and ranging (LiDAR) measurements obtained from a LiDAR sensor (e.g., equipped on an aerial vehicle that flies over a region and takes LiDAR measurements).

In some embodiments of the invention, the river flow rate server410can include a river similarity engine416that is configured to determine a degree of similarity between one or more river sites, based on the topographical characteristics of the river sites stored by the river flow rate server410. In some embodiments of the invention, the river flow rate server410can be configured to determine which river sites are within the same watershed (i.e., an area of land that drains all of the streams and rainfall into a common outlet), based on the geographic locations of the river sites. As will be appreciated by those of skill in the art, river sites that are within the same watershed will typically be affected by the same upstream factors. For example, if two rivers are in the same watershed and there is significant rainfall upstream from the rivers, it is expected that the rainfall will make its way into both rivers and increase the water level (i.e., stage) and/or flow rate of the downstream river sites of the rivers. According to some embodiments of the invention, the river similarity engine416can be configured to determine which other river sites are above a threshold level of similarity to a river site of interest. For example, in some embodiments of the invention, the river similarity engine416can compare each topographical characteristic of a pair of river sites to determine a degree of similarity of the characteristic and then determine an overall similarity score based on the various comparisons. For example, when comparing the width of river sites, the difference between two river site widths can be 10 feet (i.e., width of a first river site minus width of a second river site is 10 feet) and the river similarity engine416can assign a degree of similarity of the widths of the river sites based on a comparison of the difference in widths of the two river sites to the width of one of the river sites (e.g., a selected test river site). Thus, if a test river site has a width of 40 feet, the 10 foot difference in widths between the test river site and the second river site can be considered to be very large and thus the pair of river sites can have a low degree of similarity in relation to this characteristic, whereas if the test river site has a width of 200 feet, the 10 foot difference is much less significant and the two river sites can be considered to have a high degree of similarity with respect to this metric. According to some embodiments of the invention, a degree of similarity for each topographical characteristic can be determined using a different calculation or approach, based on the nature of the topographical characteristic. For example, with respect to vegetation, the degree of similarity of the river sites can be based on the number of matching plants found at each site or number of critical matching plants. Likewise, the degree of similarity of the river sites can be based on a degree of similarity between the slopes of the river beds at the respective river sites. In some embodiments of the invention, the overall similarity score can be a weighted average of the determined degrees of similarity of each characteristic. In some embodiments of the invention, river sites can be considered to be similar only if they are within the same watershed as one another. As will be understood by those of skill in the art, many different methodologies and/or algorithms can be used to determine an overall similarity score between two or more river sites. According to some embodiments of the invention, if the overall similarity score is above a predetermined threshold, the river sites can be classified as being similar to one another, whereas if the overall similarity score is below the predetermined threshold the river sites can be classified as being dissimilar to one another.

In some embodiments of the invention, the river flow rate server410includes a rating curve engine416that is configured to plot one or more river site data points on a chart and perform curve fitting operations on the data sets to generate a rating curve. Each river site data point can represented a measured flow rate of a river at a river site in relation to the measured river stage (i.e., height of the river). Such river data points can be obtained by measuring the flow rate and stage of a river site at various points of time. For example, a given set of river data points can be obtained over days, weeks, months or even years of observation-gathering by engineers. As described above, the flow rate of a river at a particular site can be measured using flow velocity measurement instruments operated by a field engineer. A rating curve generated by the rating curve engine416can represent the approximate or expected relationship between the stage of the river site and the flow rate of the river site, such that the rating curve can be used to extrapolate an approximate flow rate at the river site from a measured stage, without obtaining a physical measurement of the flow rate. Thus, such rating curves can allow the system to determine the approximate flow rate of a river site based on a measurement of the stage, allowing for the generation of real-time flow rate information that would otherwise be impractical to obtain through direct measurement. According to various embodiments of the invention, a rating curve can include linear, quadratic and/or exponential functions and coefficients of a fitting function. As will be understood by those of skill in the art, the rating curve engine416can apply curve fitting techniques to a plurality of data points (e.g., a set of data points associated with a river site) plotted on a graph to generate a rating curve. For example, in some embodiments of the invention, an operator of the system can specify a type of fitted curve to be used as the rating curve, such as whether it is a polynomial function (and if so, its degree) or an exponential. As will be appreciated by those of skill in the art, different types of curves may be selected by an operator based on what is most appropriate for the data set, as determined by the operator. According to some embodiments of the invention, the rating curve engine416can similarly be configured to generate a rating curve from a plurality of data sets, such as for example, data sets associated with similar river sites.

In embodiments of the invention, the stage sensor420includes a processor422, one or more sensors424and a transceiver426for measuring the stage of a river. The terms “stage of a river” is used herein to refer to the relative height of the river as the water level rises and falls due to varying conditions (e.g., increases or decreases in rainfall). According to some embodiments of the invention, a sensor424can be a radar distance measurement device that can measure the distance from the surface of a river to the radar device, although any type of known distance measurement distance can be used (e.g., a fixed measurement device such as a pole or stake having pre-marked stage heights being observed by a camera paired with image recognition and/or visual distance measurement functionality that can obtain a stage height reading based on the position of the surface of the river relative to a height marking on the fixed measurement device). According to some embodiments of the invention, a stage sensor can be affixed to the underside of a bridge that passes over a river and can thus be advantageously positioned to measure the stage of the river at any point in time. In some embodiments of the invention, the stage sensor420can be configured to continually measure the stage of a river, to intermittently measure the stage of the river or to measure the stage of the river in response to a stimuli, such as a command received from river flow rate server410. The transceiver426can allow the stage sensor420to wirelessly communicate stage readings to the river flow rate server410. Thus, based on a stage reading obtained from a stage sensor420at a river site, the river flow rate server410can be configured to determine a corresponding flow rate of the river site based on a rating curve associated with the river site.

In exemplary embodiments of the invention, downstream device(s)430includes devices that can perform some functionality in response to a river site flow rate determined by river flow rate server410. According to some embodiments of the invention, downstream devices430can include, for example but not limited to, one or more of a communication device that is configured to alert one or more individuals (e.g., via a siren, text messages, automated phone calls, emergency radio/television broadcasts, and/or the like) in an area that is downstream from the river site and is at risk of flooding based on the determined flow rate of the river at the river site, floodgates that can be opened or closed in response to an electronic signal from river flow rate server410, a dam in the river that is downstream from the river site that has mechanically adjustable aspects in response to receiving an electronic signal from river flow rate server410, floodgates that can be opened or closed in response to receiving an electronic signal from river flow rate server410, a hydroelectric power facility that has gates leading to turbines that can be opened or closed based on an electronic signal from river flow rate server410, and any other such type of device of facility on or near the river that is positioned downstream from the river site that can be affected by changes in the river flow. The flow rate data can also be stored for future reference and/or for use in calibration of a mathematical model of the river. Thus, in some embodiments of the invention, river flow rate server410can, in near real time, determine an estimate of the river flow of a river at a given river site and based on the determined river flow, can communicate with one of more downstream devices430to cause the downstream devices430to perform some function that can either take advantage of or protect against the impending water flow heading towards the downstream devices430or the surrounding areas. Thus, the system400can provide for automatic warnings of impending flooding and can automatically assist a river-based facility (e.g., a dam, a hydroelectric power facility, etc.) in optimizing its operation based on the impending downstream water flow from the river.

Turning now toFIG. 5, a flow diagram of a method500for determining an accurate river stream flow rate based on limited observations in accordance with an embodiment of the invention is shown. In one or more embodiments of the present invention, the method500can be embodied in software that is executed by computer elements located within a network that can reside in the cloud, such as the cloud computing environment50described herein above and illustrated inFIGS. 1 and 2. In other embodiments of the invention, the computer elements can reside on a computer system or processing system, such as the processing system300described herein above and illustrated inFIG. 3, a river flow rate server410described herein above and illustrated inFIG. 4, or in some other type of computing or processing environment. Although the methods disclosed herein are generally described with respect to determining an accurate flow rate of a river stream, it will be understood that it is contemplated that the disclosed methods may also be applied to streams, channels, ditches or any other such environments that facilitate streams.

The method500begins at block502and includes receiving (e.g., via river flow rate server410) a limited sample of flow rate data associated with a test site of a test river. Flow rate data can refer to a plurality of data points, where each data point of the plurality includes a measured flow rate plotted in relation to a measured river stage. For example,FIG. 6Ashows an example chart where two sets of data points (i.e., “River 1 Data” and “River 2 Data”) relating to two respective river sites are plotted on the chart. As shown, for each set of data points, a rating curve (i.e., “River 1 Fit Curve” and “River 2 Fit Curve”) can be generated to represent the projected and/or expected relationship between the flowrate and the stage for each of the two river sites. For example, as described previously above, rating curve engine416of river flow rate server410can apply curve fitting techniques to each set of data to generate the respective rating curves. In this example, the two data sets are from two different river sites that are similar (e.g., as determined by river similarity engine414), and thus the rating curves for each respective river site follow a similar pattern or trajectory.

According to some embodiments of the invention, a limited sample of flow rate data can be flow rate data that is insufficient for constructing an accurate rating curve. According to some embodiments of the invention, a limited sample of flow rate data can be a number of data points that is less than a predetermined threshold number of data points. According to some embodiments of the invention, an accurate rating curve can be considered to be a rating curve that is above a threshold level of accuracy or above an R-squared (R2) value. As will be appreciated by those of skill in the art, an R2value is a statistical measure that represents the proportion of variance for a dependent variable that is explained by an independent variable or variables in a regression model. For example, if an R2value is “0.5”, this represents that half of the observed variation can be explained by the model's inputs. An R2value can be determined by taking data points of dependent and independent variables, and finding the line of best fit (e.g., a rating curve) based on for example, a regression model, calculating predicted values (e.g., predicted flowrates based on the corresponding stage shown on the rating curve or predicted stages based on corresponding flow rates shown on the rating curve), subtracting the actual values (e.g., measured flow rates and/or measured stages) and squaring the results. Thus, in some embodiments of the invention, a limited sample of flow rate data can be a number of data points that when used to generate a rating curve, generates a rating curve having an R2value of less than a predetermined threshold. In some embodiments of the invention, the system may determine whether the sample of flow rate data is a limited sample that is insufficient for constructing an accurate rating curve by using an iterative process of building rate curves with varying numbers of data points and observing the degree of variation to the resulting rating curves. For example, a first curve may be generated based on a data set with N data points and then a second rating curve may be generated using N−1 data points and a degree of difference between the two curves may be measured, and the process may be repeated with N−2 data points and so on. If the difference between two rating curves exceeds a threshold, then at least one of the data sets corresponding to those rating curves (e.g., the one with less data points) may be considered to be a limited sample that is insufficient for constructing an accurate rating curve. Those of skill in the art will recognize that various metrics or combinations of metrics may be used to characterize “the difference” between two curves, such as for example, the average distance between points of the curve as measured across one axis of the graph (e.g., the difference in Y-axis values for each X-axis value), use of a sum of squared difference, use of absolute values at multiple grid points, or any other such methods as may be selected by one of skill in the art.FIG. 6Bdepicts an example of a third data set (i.e., “River 3 Data”) that is much smaller than the first two data sets. As shown inFIG. 6C, if a rating curve were to be generated using the third data set alone, it would be vastly different than the other two rating curves derived from similar river sites. In this example, the third set of data is from a river site that is similar to the first two river sites (e.g., as determined via river similarity engine414), and thus a rating curve for this river site would be expected to follow a similar path or trajectory as the first two rating curves, but because it is based on such a sparse amount of data, there is a large room for error and the resulting rating curve is very inaccurate. Thus, as shown byFIG. 6C, there is a need for a way of generating an accurate rating curve in cases where only sparse data is available for a given river site.

At block504, the method includes determining (e.g., via river flow rate server410) topographical characteristics of the test site. According to some embodiments of the invention, the topographical characteristics of a river site can include one or more of a slope of a river bed, a cross-sectional width of a river and a distance to a downstream lake or reservoir. In some embodiments of the invention, the topographical characteristics can be determined by river flow rate server410based on user-input measurements of topographical features of the test river site, measurements obtained from mapping resources (e.g., via third party mapping services hosted on the Internet), and/or readings from devices (e.g., LiDAR measurements) used to obtained measurements of the river site, or some combination of the preceding methods.

At block506, the method includes determining (e.g., via river flow rate server410) a plurality of similar tested sites. According to some embodiments of the invention, a similar tested site can be a river site having topographical characteristics that are above a threshold level of similarity to the topographical characteristics of the test site and about which sufficient flow rate data has been collected for generating an accurate rating curve. In some embodiments of the invention, flow rate data can be considered to be sufficient for generating an accurate rating curve if the number of data points in the flow rate data is equal to or above a predetermined threshold or if an R2value of a rating curve generated from the flow rate data exceeds a predetermined threshold. According to some embodiments of the invention, determining the plurality of similar tested sites can include determining that for each similar tested site of the plurality of similar tested sites, each topographical characteristic of the similar tested site is within a respective threshold range of a corresponding topographical characteristic associated with the test site. As described above, in some embodiments of the invention, river similarity engine414can determine a degree of similarity between two river sites based on a comparison of one or more topographical characteristics associated with the river sites. If the degree of similarity exceeds a predetermined threshold, then river similarity engine414can classify the two river sites as being similar. In this way, the river flow rate server410can identify one or more other river sites that are similar to the test river site, such that the relationships between the stage and the flowrate at the test river site and the identified similar river sites can be expected to be similar as well. Thus, the data points of the similar river sites can be combined with the limited sample of flow rate data associated with the test river to create a more complete data set for generating an accurate rating curve that is associated with the test river site.

At block508, the method includes generating (e.g., via river flow rate server410) a test site rating curve based on a combination of the limited sample of flow rate data and the sufficient flow rate data of one or more of the plurality of similar tested sites. According to some embodiments of the invention, generating a test site rating curve can include applying a curve fitting algorithm to the combination of the limited sample of flow rate data and the sufficient flow rate data of one or more of the plurality of similar tested river sites. For example, as shown inFIG. 6D, the data sets of the first two river sites (i.e., “River 1 Data” and “River 2 Data”) can be combined with the sparse data set of the third river site (i.e., “River 3 Data”) and collectively used to generate a new rating curve (i.e., “River 1, 2, 3 Fit Curve”) that can be used to more accurately approximate the stage-flowrate relationship of the third river site. As shown, this new rating curve more closely tracks the rating curves of the original two data sets, which is expected given that all river sites are similar in terms of their topographical profiles. According to various embodiments of the invention, a sparse data set (i.e., a limited sample of flow rate data) associated with a test site can be combined with one or more non-sparse data sets associated with one or more other similar (i.e., having similar topographical features) river sites to create a new non-sparse data set sufficient for use in creating an accurate rating curve in association with the test river site.

At block510, the method includes obtaining (e.g., via river flow rate server410) a stage reading associated with the test site from a sensor disposed at the test site. As discussed previously, the terms “stage reading” as used herein refers to the height of surface of a river relative to some reference height. According to some embodiments of the invention, the sensor disposed at the test river site can be a radar distance sensor disposed at a fixed position above the test river site. For example, a radar distance sensor can be positioned on the underside of a bridge such that it can transmit a radar pulse at an approximately perpendicular angle to the surface of the river.

At block512, the method includes determining (e.g., via river flow rate server410) a flow rate of the test site based on the stage reading and the test site rating curve. For example, rating curve engine416of river flow rate server410can identify a point on the rating curve associated with the test site that corresponds to the measured stage and then determine the flowrate that corresponds to that point on the rating curve.

Once obtained, the determined flow rate of the test site can be utilized to automatically execute a number of different functionalities (e.g., via downstream device(s)430). For example, in some embodiments of the invention, the method can further include determining an amount to open a downstream floodgate based on the flow rate of the test site and automatically causing the downstream floodgate to open the determined amount. For example, the river flow rate server410can communicate with a downstream device430that controls the floodgate and cause the floodgate to open and/or close based on the determined flowrate at the test site. According to some embodiments of the invention, the method can further include obtaining continuous stage readings associated with the test site, determining continuous flow rates of the test site based on the continuous stage readings associated with the test site, and dynamically adjusting the size of an intake opening to the turbine in response to dynamically determining an amount to adjust a size of the intake opening to a turbine based on the flow rate of the test site to improve or optimize the operation of the turbine based on the river flow. In some embodiments of the invention, the method can include determining an estimated time of flooding at a downstream location based on the flow rate of the test site and automatically transmitting a flood warning to one or more devices associated with individuals proximate to the downstream location (e.g., based on location data of the one or more devices). Thus, in some embodiments of the invention, system400can be deployed as an early warning system in association with a river site in which very little previous data has been gathered, avoiding the need for expensive and protracted data gathering prior to providing the benefits of automatic floodgate/intake opening control and/or flood warnings.

FIG. 7depicts a flow diagram of a method700for determining an accurate river stream flow rate based on limited observations in accordance with an embodiment of the invention is shown. In one or more embodiments of the present invention, the method700can be embodied in software that is executed by computer elements located within a network that can reside in the cloud, such as the cloud computing environment50described herein above and illustrated inFIGS. 1 and 2. In other embodiments of the invention, the computer elements can reside on a computer system or processing system, such as the processing system300described herein above and illustrated inFIG. 3, a river flow rate server410described herein above and illustrated inFIG. 4, or in some other type of computing or processing environment.

The method700begins at block702and includes receiving (e.g., via river flow rate server410) a sparse data set associated with a test river site. A data set can include a plurality of data points where each data point represents a measured stage and a corresponding measured flow rate of a river site. A sparse data set can be a data set is made up of a number of data points that is less than a predetermined threshold or that is insufficient to generate an accurate rating curve, as previously described above.

At block704, the method700includes identifying (e.g., via river flow rate server410) one or more other similar river sites having non-sparse data sets. For example, as described previously above, rating curve engine416can identify one or more river sites that are similar to the test river site, based on a comparison of the topographical information associated with each site.

At block706, the method700includes receiving (e.g., via river flow rate server410) one or more non-sparse data sets associated with the one or more other similar river sites. A non-sparse data set can be a data set having a number of data points that exceeds a predetermined threshold or that is sufficient for use in generating an accurate rating curve.

At block708, the method700includes generating (e.g., via river flow rate server410) a rating curve based on the combination of the sparse data set and the one or more non-sparse data sets. For example, river flow rate server410can apply curve fitting techniques to the collection of data points made up of the sparse data set and the one or more non-sparse data sets to generate a rating curve that best fits all of the data points. According to some embodiments of the invention, as more data points are generated through measurement (i.e., as data points are added to any data set), the rating curve can be recalculated based on the combination of data sets and the new additional data points. As will be understood, adding more data points for use in generating a rating curve will generally cause the resulting rating curve to be more accurate. Thus, according to some embodiments, a rating curve generated based on a sparse data set can be iteratively updated by rebuilding the curve each time a new data point is obtained at river site associated with the sparse data site. Likewise, the rating curve can also be iteratively updated if additional data points are obtained at river sites associated with the similar river sites having non-sparse data sets.

At block710, the method700includes receiving (e.g., via river flow rate server410) a stage measurement associated with the test river site. For example, as described previously, a stage sensor420disposed at the test river site can obtain a stage measurement from the river site and transmit the stage measurement to the river flow rate server410.

At block712, the method700includes determining (e.g., via river flow rate server410) an approximate flowrate at the test river site based on the stage measurement and the rating curve. For example, the river flow rate server410can reference a point on the rating curve that correlates to the stage measurement and determine the flowrate that corresponds to that point on the rating curve. As described previously above, the determined flowrate can then be utilized by the river flow rate server410to generate alarms or cause one or more downstream device(s)430to take some action.

Additional processes can also be included. It should be understood that the processes depicted inFIGS. 5 and 7represent illustrations, and that other processes can be added or existing processes can be removed, modified, or rearranged without departing from the scope and spirit of the present disclosure.