Salt Dilution Method
Salt dilution method is used in mountain rivers with rough cross section, big boulders and turbulent flow. An electrical conductivity (EC) meter was used for discharge measurement. Salt dilution method is particularly used for measurement of flow in mountainous stream and any other sites where high degree of turbulence exists to ensure complete mixing of injected solution in the pre-determined length of the channel. Under such condition of flow, the conventional approach to flow gauging such as current meter or calibrated structure are not feasible. NaCl was used for discharge measurement with the salt dilution methods. The amount of salt to be injected depends on flow estimation flow (generally 5 g/l). The salt was dissolved properly in a bucket. Then this solution was injected at once in the stream water almost 100 m from point of measurement. Base level conductivity of water was noted. As the salt reached to the place of measurement, the conductivity value started changing. The conductivity values were noted with 5 second interval. This was done until the measured value reached the base level conductivity again (Hofer, 1998). The rate of flow in channel (Q) can then be calculated by:
Q = qN
Where q = the rate of injection of solution and,
N = dilution ratio determined by direct measurement of concentration.
In Hilkot watershed discharge in l/s was calculated in MS Excel macros.
Volumetric Method
Volumetric method is simple way to measure discharge of water directly in the bucket, at known time. This method is applicable where discharge is very low.
Q=V_t/T
Where Q = discharge (l/s)
Vt = Total volume (liter)
T = Time (second)
Flood Hydrograph
A flood hydrograph shows how a s...
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...y for very short duration. The attempt has to be made to measure as many high flows as possible at all the hydro-stations.
Measured All measured values were plotted for stage –discharge relationship for all hydro stations. Regression analysis using Polynomial transform was used to develop relationships of discharge as function of a gauge. Rating curves for all the hydro stations were established and R2 values shows very strong correlation at all the hydro stations except hydro station No.5. CorelationCorrelation at hydro station No.5 was week is not very strong due to small limited number of observations, ,access to the area during high flood resulting . Low number of observation gives lless correlation value. The R2 values and regression equations established for different stations are shown in the table below. All five rating curves are shown in the Fig.3.
Construct a manual calibration plot of experimental absorbance versus actual Ca2+ concentration (pink line) using finely lined graph paper. Include proper title and figure #. Label the axes. Using the same graph paper plot experimental absorbance versus experimental Ca2+ concentration (green line). Include a legend to identify both lines
Within a river there are areas known as pools and riffles. The pool is an area of deeper slow moving water, whereas the river is an area of shallow, fast flowing white water. The rocks are also clearly visible at the riffle, but submerged in the pool. A pool is usually found on a meander whereas the riffle is normally seen on the straighter areas of the channel, they tend to be situated very close to one another, forming in sequences. The aim of this investigation is to carry out a field investigation at a pool and riffle and compare the characteristics at these two sites with the objective to state the differences.
Check if there are any leaks especially around the stopcock, the valve at the bottom of the buret. When it comes to calibration, it is calibrated by transferring water into an Erlenmeyer flask and weighing it using an analytical balance. This is done for two (2) trials, each with varying amounts of water. Erlenmeyer’s mass is pre-recorded before transferring water from the buret. The volume delivered by the buret is considered the apparent, which means evident, volume. Before starting another set, the flask should be clean and dry to avoid any error. The water inside the flask will add the volume to be transferred thus making the mass of water higher than what it should really be. The mass of water obtained thru weighing by difference would then be multiplied to the buoyancy of water at the recorded temperature which will then be the corrected mass of the water. The corrected mass of the water is then divided by the density of the water, at the same temperature, and will be considered as the true mass. Correction value can be obtained by solving for the difference between the true volume and the apparent volume. Some of the correction value computed are negative and it only means that there is an error that occurred. One of the possible errors in most volumetric glassware’s is reading the wrong volume. Volume must be read based on the lower meniscus at eye
...f the streams and drainage basins were found using the Calculate Geometry tool in ArcMap. This information gave us the minimum, maximum, average, and total stream lengths, along with the area of the drainage basins. Once this information was obtained it was used to calculate morphometric relationships (table 1). The sinuosity of the BRV was determined through a custom built tool in ArcMap that took the length of the stream over the length of the valley.
The Niagara River is very unique in the way that it drains water along the ninety-nine meter elevation drop down which it flows. The water drained differs according to the time of the day and the season as some water is diverted to create hydroelectric energy. The volume of water during the day over the Niagara Falls when it is tourist season, April 1st to October 31st, must not be less than 2,832 m3/s. During the winter months, anything not in the tourist season, the water flow over the Fa...
Electrical conductivity refers to a substances ability to carry moving electrons (conduct electricity). In order to do so, there must be a supply of delocalised electrons. While in a solid state, ionic substances can not conduct electricity as there are no delocalised electrons or free/mobile ions to act as charge carriers. In an aqueous ionic solution, the H2O molecules break apart the crystal lattice structure of the ionic substance into individual ions, surrounding each ion in a jacket of hydration. Below is the equation that describes the dissociation of NaCl when in H2O solvent.
The Flow rate estimation of residential sewage is based on population numbers. The flow rate varies on daily and weekly cycles basis, the variation is in the range of 0.5...1.5 times average flow. Industrial effluent should be estimated on a case by case basis, depending on the plant type. The amount of leakage water present depends on a number of variables, such as water table level, local rainfall and soil characteristics and general condition of the subterranean pipework. It can be estimated as units per pipeline length unit, e.g. kilometer or as a ratio related to quantity of the sewage.
Levi, E. The Science of Water. The Foundation of Modern Hydraulics. New York, USA: ASCE Press.1995.
Observation Well: The readings of the 4-Observation wells are below the water level of the dam. OW8 and OW4 are located at the dam toe showing that the water levels are close to the tailwater level. For OW3 located at the middle level of the Saddle dam, show that the water level is close to the water level of the dam. Lastly, OW5 which is located far from the main dam, shows that the water level is below the water level of the dam. In addition, based on the alarm levels established through historical data (Damwatch database,2015), readings are within the allowable.
...t into the reservoir on average per year, in time, this silt could accumulate behind the walls of the dam, clogging the turbines' entranceway. Further, the absence of silt down stream would have two dramatic effects:
and discharge can be worked out by use of equations. In order to get a
Salinity is simply the amount of salts contained in the soil which is estimated by measuring the electrical conductivity of a removed soil solution. An electrical device can easily measure the amount of salt contained in the soil. In millimhos/cm or micromhos/cm, a salt concentration of a gram per litre is about 1.5 millimhos/cm).
As a non-structural measure, flood forecasting (such as discharge, water level, or flow volume) is a crucial part of flow regulation and water resources management. Worldwide, flood disasters account for about one-third of all natural disasters in terms of number and economic losses (Berz 2000). As stated by Dutta and Herath (2004), out of the total number of flood events in the world during the past 30 years, 40% occurred in Asia and Southeast Asia countries stand for the second worst region in Asia. ASEAN Disaster Risk Management Initiative (2010) reported that a catastrophic 200-year flood (0.5 percent annual probability of exceedance) would have a major impact on the economies of the Southeast Asian countries, including Myanmar, which are already fragile. The process of floods is basically complex, uncertain and unpredictable, due to its nonlinear dependency on meteorological and topographic parameters (Thirumalaiah and Deo 1998). While distributed hydrological modeling involves multidisciplinary and complex issues, simple, robust and sustainable approaches in flood forecasting system are needed, without much effort in continuous updating such models. For flood forecasting to be effective, it must provide flood warnings with a reasonable lead time. Furthermore, for real time operation, the authorities may require to access the gauges of significant predictors (Corani and Guariso 2005), thus saving considerable costs, a critical issue in developing countries.
“Anyone who can solve the problems of water will be worthy of two Nobel Prizes - one for Peace and one for Science”, stated by John F. Kennedy. Since the beginning of civilization, mankind has faced tribulations allied with river and its flow. With increase in utilization of water resources; flow in river channels are gaining significant importance among the research scholars. More and more complicated problems are encountered due to multipurpose use of alluvial rivers.
The purpose of this experiment is to use our knowledge from previous experiments to determine the exact concentration of a 0.1M sodium hydroxide solution by titration (Lab Guide pg.141).