Based on the Offer of NMAqua d.o.o. and the Contract with the contractor HKP Consulting from Banja Luka, on the measurement of the flow of mixed sewage at one sewage outlet in Milići, "NMAqua" d.o.o. is in the period from 21.06.2024. until July 2, 2024. performed the services defined by the contract in question
Programming of sewage meters
Sewage meter installed
Measurement in progress
After the hydrometeorological conditions were created and in agreement with the customer, we installed and programmed the Hydreka MainFLO flow meter with a doppler speed sensor and a pressure level sensor in a DN 500mm profile pipe in Milići.
After the measurement and analysis, it was concluded that it is a mixed collector, because during two events, a larger amount of water was released, which are related to precipitation in the same period of time.
The Municipality of Gacko, in order to solve the water supply of the population of this municipality, has announced a tender for the "Ideological solution for rehabilitation, reconstruction and development of the Gacko water supply system".
For the purposes of this project, we were engaged by the contractor "CPK" Banja Luka with the project task "Flow measurement with portable ultrasonic flow meters and pressure measurement with digital portable loggers on pipelines managed by JP "Vodovod" a.d. Gacko"
Therefore, it was necessary to measure the balance, that is, the amount of water on the water supply system managed by "Vodovod" a.d. Gacko, and the total length of the distribution network is about 70 mi.
Preparation for measurement
Flow measurement from the reservoar
Setting the parameters for measurement
The first phase of this project related to the measurement of the capacity of the spring "Vratlo" from which the municipality of Gacko is supplied, and the incoming and outgoing volumes of water at all reservoirs.
The distribution network in the city part of Gacko is organized into two supply zones: a higher zone that is supplied from the Gacko 2 reservoir and a lower zone that is supplied from the Gacko 1 reservoir. In addition to these two reservoirs, measurements were also made in the Samobor, Kula and Stepen reservoirs.
In this measurement phase, it was necessary to measure the flow of water at the entrances to the tanks and the water leaving the tanks, as well as the pressures on the water supply network. Flow and pressure measurements were carried out for each specified measuring point 24 hours continuously, rounding the measurement units and including them so that the results can be used for the calculation of water balances and the creation of a mathematical model of the water supply system with hydraulic supply calculation.
In addition, for this phase of the works, it was necessary to perform measurements with mobile ultrasonic flow meters at consumers, namely:
- individual housing in the city area, - individual housing rural area, - collective housing - buildings (newer and older constructions), - public institutions, - big economy companies, - small economy companies
The flow measurement was carried out during this phase of the project at 38 measuring points with six ultrasonic flow meters, and pressure measurement with digital loggers at 10 measuring points.
The work on measuring the flow and pressure, with the preparation of the measuring points, lasted continuously for eleven days. For each measurement point, the measurement cycle lasted 24 hours, with the default measurement interval for both measurement parameters being 1 minute.
The measurement was carried out in extremely difficult conditions, because during this work there were partial reductions in the water supply system. With the understanding of the management of KP "Vodovod" Gacko, we adjusted the reductions, in order to have conditions for measuring rounded hydraulic units.
For this measurement phase, we also had great, selfless help from the employees of KP "Vodovod" a.d. Gacko. In addition to helping us get acquainted with the water supply network and the functioning of the water supply system, they also provided us with the necessary technical assistance.
With their help our NMAqua team fully fulfilled all requirements from the project assignment.
The second phase of the project in the coming period foresees additional measurements on the water supply system, i.e. pipelines, where mathematical calculations show the existence of differences, i.e. losses. It will also be necessary to carry out testing and detection of losses on certain parts of the water supply system and finally final measurements after all analyzes and reduction of losses on the water supply network of the municipality of Gacko.
Tunicipality of Lopare together with JKP "Vodovod" d.o.o. Lopare has prepared a program of works for the rehabilitation of water losses in the water supply system of Lopare. The main goal of the aforementioned Program of Works is to define losses, i.e., uncontrolled leakage from the water supply network, which will be removed through other activities. After the preliminary actions in terms of collecting technical data on the water supply system and data on consumers, as well as the preparation of cadastral documents, we started to measure and balance the amount of water in the system. The flow was measured at eight measuring points for 24 hours.
De measured the pressure on the entire water supply system at nine measuring points, including the lowest and highest elevations. In addition to the mentioned works, during the measurement, the manipulation of the sector closures was also carried out in order to balance the amount of water in certain parts of the system. Noise loggers were deployed at 18 locations, and after analyzing all the results, control and testing of certain parts of the water supply network was carried out, and faults were located.
Practical training was also carried out for working with the "Fuji" brand correlator in the field during the investigation of faults in parts of the water supply network. All the results were summarized, and after the analysis, a report was drawn up on the measurement and examination of losses in the distribution network of Lopar with a proposal to the investor to divide the implementation of the recovery of losses in the water supply system of Lopar into short-term, medium-term and long-term activities, which are also listed in the report.
Based on the Terms of Reference for the Development of the Reconstruction Project of the local water supply system Međudražje in the settlement Međudražje - MZ Zavalje - City of Bihać, Center for Design and Consulting d.o.o. Banja Luka hired us to perform a 48-hour flow measurement at a pre-determined measuring point in the reservoir.
As part of the project task, among other things, it was necessary to measure the flow in order to see and assess the abundance of springs and available water, for the settlement Međudražje, and at the entrance to the reservoir from the spring.
In order to fully understand the condition of the source and the capacities currently available in the distribution of drinking water, the measurement was performed with an ultrasonic portable flow meter AQF 2000.
The ultrasonic flow meter is installed on the LŽ 80mm pipeline and programmed for a measurement interval of 1 min in a time period of 48 hours.
After the measurement, a report was made with accompanying photo documentation, a measurement diagram and an overview of the minimum, maximum and average flow at the inlet to the tank.
Due to the need to measure the flow in order to assess the available quantities of water, as well as the condition of certain parts of the water supply system Public Utility Company "Kraljeva Gora" d.o.o. Han Pijesak contacted us again with a request for the mentioned works.
In mid-October, 24-hour flow measurements were performed at pre-determined temporary and control measuring points with ultrasonic portable flow meters AQF 2000.
The flow meters are distributed from the Javornik reservoir along the entire network to the end consumers in the settlements of Džimrije, Mrkalji, Mironja and Ljeskovac, so that the condition of the water supply network could be better understood.
Based on the performed 24-hour measurements, as well as control current measurements, it is evident that there are evident losses on most parts of the pipeline network of the water supply network of JKP "Kraljeva Gora" Han Pijesak.
They are especially pronounced in the lower lower parts, where the pressures are the highest and where the water supply network is the oldest, ie in the city center.
Na osnovu potreba vršenja mjerenja protoka i pritiska u cilju sagledavanja raspoloživih količina vode, kao i stanja vodovodnog sistema sa filterskog postrojenja “Tilava” sa kojeg se snabdijeva veći dio opštine Istočno Sarajevo, izvršili smo u prvoj fazi početna terenska mjerenja protoka i pritisaka na unaprijed utvrđenim stalnim i privremenim-kontrolnim mjernim mjestima.
In order to fully understand the state of the network and the capacities available in the distribution of drinking water, in addition to measuring flow and pressure, which were used for analysis, from permanent measuring points, ie measuring DMA zones, measurements were performed with ultrasonic portable flow meters. as well as measurements with portable digital pressure gauges.
Pressure measurement on MMP1 was performed in the underground hydrant in the street of the First Sarajevo Brigade near "Adiko" bank in the time of 48 hours with a measurement interval of 1 min.
After the pressure logger was dismantled, the data was read and diagrams were made.
In order to improve the situation in the water supply of KP "Vodovod i kanalizacija" a.d. East Sarajevo and maintained the trend of continuous water supply without reductions, it is necessary to implement measures and interventions on the existing water supply and communal infrastructure, and above all to strengthen the detection and elimination of failures in order to save the amount of water currently available.
Based on the needs of measuring the flow and locating faults in the water supply system in Kreševo, the customer Hydro Control “d.o.o . Ilidža in the capacity of the Purchaser and NMAqua s.p Dejan Predojević in the capacity of the Contractor, performed field measurements and control of consumers and pipelines in the period from 11.03. to 13.03.2021. years.
According to the previously performed works on the water supply system JKP “Kostajnica” Kreševo and the Minutes from the field visit within the Project “Improvement of water supply in the municipality Kreševo” and the performed step test on the branch of the Meljine reservoir from by the client, it was necessary to perform micro-location of the area of losses on the specified part of the water supply network.
Flow measurement in subzones
It was also necessary to measure the flow and control the parts of the network where the illogical difference in the amount of flow at the measuring points is shown, for the part of the water supply network from the Meljine reservoir, which according to the previous step test suspected significant losses.
Measurement of quantities in the Meljine reservoir
Due to more expeditious work and research of illegal consumption and locations of uncontrolled consumption, ie losses, three flow meters were installed on the part of the main water supply network, which needed to be examined based on the results of the step test. Based on the results of measurements and analysis, parts of the water supply network were determined, on which it was necessary to perform detailed research.
By installing a flow meter in the Meljine reservoir, the amount of water entering the reservoir was measured, as well as the amount of water leaving the reservoir. Meters were placed before the water meter at the inlet and after the water meter at the outlet, where the most favorable conditions for measurement existed. After the measurement, a difference in the amount of water entering the tank between the water meter and the meter was observed.
After the first phase of flow measurement and research of losses and analysis of measurement results, and according to the Activity Plan, during May on the part of the water supply network supplied from the Meljine reservoir ultrasonic flow meters were installed at measuring points where there were even the smallest conditions for correct measurement.
The measuring points were determined in order to get the most complete insight into the distribution of the amount of water coming out of the Meljine reservoir on the part of the network where there are certain losses. During the measurement, three measuring points for all-day metering, seven places for control instantaneous metering and two metering points according to consumer business facilities were determined.
Simultaneously with the installation of the flow meter at the measuring points, the installation of the noise recorder was performed. The results of noise recording showed that the noise level does not indicate the existence of failures in the parts of the water supply network where they are installed.
After the completion of works on control, measurement and testing of pipelines and connections, it is estimated, based on the measured flow values, that about 4 l/s of uncontrolled water leakage on the water supply network was detected in the form of located faults.
According to the measurement data, considering the measured flow of the entrance to the Meljine reservoir of 8,145 l / s before detecting faults, night output of 6,606 l / s, the calculation gives a loss of about 80%, while reducing the night by 4 l / s faults on 2,606 l / s received a loss of about 32%.
Based on the conclusions on the conducted measurements and analysis of the results, Proposals for further activities to reduce losses and establish stability in the water supply system of the municipality of Kreševo were defined and presented. They need to be implemented as soon as possible in order to have a stable water supply of the population and economic capacities during the reduction of spring capacity, as well as increased consumption during the summer period.
Based on the accepted Offer, on the performance of the service of measuring flow and pressure between "ELNOS"Banja Luka in the capacity of the Purchaser and"NMAqua“Dejan Predojević s.p. Banja Luka, as the contractor, in December 2020, the measurement was performed.
The current pressure measurement was performed with two digital meters and flow measurement with one ultrasonic flow meter on the pipeline Ø700mm at the entrance to the mini hydro-power plant "Sithonia" in Gornji Podgradci.
Flow measurement on the inflow pipeline to the hydropower plant
Instantaneous flow measurement was performed ultrasonic flow meter on spirally welded steel pipeline of nominal profile Ø700 mm, where there were normal conditions that meet the technical requirements of precise measurement, ie on the rectilinear part of the pipeline.
Hydropower turbine pressure measurement
Pressure measurement was performed with two digital pressure gauge at an interval of 1 sec at two measuring points. The first pressure gauge is placed at the inlet to the plant, and the second is placed directly on the turbine.
As part of the continuation of the conceptual solution of the problem of water supply from the spring on the water supply system of the forestry Gorica in Šipovo, flow measurement and pressure control were performed.
By measuring the flow of water on the two catchments from which the said water supply system is supplied, the available quantities were determined, ie their yield.
By visiting and visually inspecting the part of the indented pipeline 100 mm from the catchment to and behind the connection point, the problems that need to be eliminated in the next period in order for the system to be functional were also determined.
By recording the height elevations of the pipeline, for which there has been no documentation of this type so far, and by making a longitudinal profile, a plan of necessary repairs will be made. In addition to the rehabilitation of existing facilities, as well as the replacement of certain fittings and valves in line shafts and overflow chambers, it will be necessary to build some additional facilities, in order to put the network in the length of about 6 km into operation.
Pressure measurement with control was also performed on the air valve which has the function of reducing the pressure towards the chamber-tank Čardak.
As long-term associates, we received an invitation from the management of the company "Peštan" to help them solve problems in the plumbing installation-hydrant network.
The leak was very difficult to notice, because the intensity of water leakage is very low. At the same time, the pressures in this part of the city's water supply network oscillate a lot, which makes it difficult to locate the place of water loss.
As this is a water supply network within the company, which is known to us from previous research, the job of locating a fault on the hydrant network has been made easier, considering the time required.
The correlation method narrowed the circle to the part of the hydrant network around the last building-hall to the north.
As a small part of the network remained, a visual inspection of the terrain around the building, which is in the same range - earth and asphalt surface, was performed. There were no visible signs of loss on the ground, but an inspection of the manholes with plumbing fittings revealed a fault in the manhole at the Ø80 mm pipe connection fitting.
LOCATED LEAK
By measuring with an ultrasonic flow meter on the part of the network that remained for the loss investigation, and which was isolated, approximately the same amount of water was determined on the basis of the issued bill for the consumed water for a month.
