Tehničke smernice za obezbeđivanje protivpožarne vode iz javnih vodovodnih sistema

In many European countries as well as in America there is no current common legislation requiring that public waterworks provide fire flows. Most public water supply systems provide fire water services to their community. In our country public waterworks do not have any decrees, regulations or technical norms either at state or local levels regarding fire flow supply from the public water supply system. Criteria for providing fire water and their classification are analyzed in this paper. Guidelines are recommended based on the determined parameters and criteria to improve the fire water supply from public distribution water systems. Recommended Technical guidelines are in compliance with the new Fire Prevention Act [19].U mnogim evropskim zemljama i Americi trenutno nema jedinstvenih zakona koji od javnih vodovodnih kompanija zahtevaju da obezbede protivpožarne protoke. Većina javnih vodovodnih sistema pruža protivpožarne usluge zajednici koju opslužuju. U našoj zemlji javna vodovodna preduzeća ne poseduju uredbe, propise i tehničke normative u vezi sa obezbeđenjem protivpožarnog protoka iz javnog vodovodnog sistema, kako na državnom tako i na lokalnom nivou. U radu je prikazan predlog tehničkih smernica-preporuka za poboljšanje obezbeđivanja vode za protivpožarne potrebe iz javnih vodovodnih distributivnih sistema. Predlog tehničkih smernica je usaglašen sa novim Zakonom o zaštiti od požara

Mathematical modelling of flow and sediment transport – the Tisa dam case study

Velike brzine toka nizvodno od brane na rijeci Tisi kod Novog Bečeja (Srbija), uzrokovane velikom razlikom u vodostaju između uzvodnog i nizvodnog toka, dovode do erozije obale na desnoj strani neposredno nizvodno od pomoćnog preljeva, zbog čega je ugrožena i stabilnost brane. Imajući u obliku složenu interakciju parametara toka i pronosa nanosa na toj lokaciji, u radu se koristi pristup utemeljen na prostornom (3D) matematičkom modelu tečenja i pronosa nanosa koji je namijenjen za rješavanje takvih složenih procesa. Modelom je definirano optimalno rješenje koje udovoljava svim zahtjevima stabilnosti analiziranih građevina, pri čemu se uspoređuju rezultati dobiveni analizom postojećih uvjeta s rezultatom mjera koje se predlažu za rješavanje problema.High flow velocities downstream of the Tisa Dam at Novi Bečej (Serbia), produced by the large difference between water levels in the upstream and downstream reaches, cause bank erosion by the right bank immediately downstream of the emergency spillway, threatening stability of the dam itself. Due to complex interaction between the parameters of flow and sediment transport at the given location, an approach involving a spatial (3D) mathematical model of flow and sediment transport, aimed at solving such complex processes, is investigated in this paper. An optimum solution meeting all requirements for the stability of structures in question has been reached by the model, through comparison of the results generated by the existing conditions with the result provided by the measures proposed to fix the problems

Tehničke smernice za obezbeđivanje protivpožarne vode iz javnih vodovodnih sistema

In many European countries as well as in America there is no current common legislation requiring that public waterworks provide fire flows. Most public water supply systems provide fire water services to their community. In our country public waterworks do not have any decrees, regulations or technical norms either at state or local levels regarding fire flow supply from the public water supply system. Criteria for providing fire water and their classification are analyzed in this paper. Guidelines are recommended based on the determined parameters and criteria to improve the fire water supply from public distribution water systems. Recommended Technical guidelines are in compliance with the new Fire Prevention Act [19].U mnogim evropskim zemljama i Americi trenutno nema jedinstvenih zakona koji od javnih vodovodnih kompanija zahtevaju da obezbede protivpožarne protoke. Većina javnih vodovodnih sistema pruža protivpožarne usluge zajednici koju opslužuju. U našoj zemlji javna vodovodna preduzeća ne poseduju uredbe, propise i tehničke normative u vezi sa obezbeđenjem protivpožarnog protoka iz javnog vodovodnog sistema, kako na državnom tako i na lokalnom nivou. U radu je prikazan predlog tehničkih smernica-preporuka za poboljšanje obezbeđivanja vode za protivpožarne potrebe iz javnih vodovodnih distributivnih sistema. Predlog tehničkih smernica je usaglašen sa novim Zakonom o zaštiti od požara

Rationalisation and reliability improvement of fire-fighting systems - the Novi Sad case study

Water supply systems are commonly used to supply fire-fighting water in most EU countries. To provide fast access to water, the standard practice is to install a huge number of hydrants along the entire water supply network. Pipe diameters and working pressures in the network are designed for a combination of the maximum hourly water demand and fire-fighting needs. However, in poorly managed water supply systems most of the hydrants are out of order. Although hundreds of hydrants exist in the network, the reality is that fire water tankers are usually refilled at just a few locations that are equipped with reliable hydrants maintained by the fire brigades. This paper presents a somewhat different approach for the provision of fire-fighting water. The approach discussed in the paper is based on the concept being introduced in the city of Novi Sad, Serbia, by cooperative efforts of the municipal Water Supply and Sewerage Company and the fire-fighting service. In addition to presenting the experience gained in the case study, some generic conclusions are drawn. As an alternative to having a number of unreliable and small hydrants distributed throughout the network, the new concept proposes the construction of several strategically positioned filling stations, with high-flow-rate pillar hydrants and good access roads for the manoeuvering of fire water tankers. If properly designed and distributed around the city, such filling stations would increase the reliability of fire-fighting operations. The filling stations' design methodology presented in this paper is composed of a fire-risk spatial assessment, a hydraulic check of water supply network operations and a worst-case traffic load analysis. By employing the proposed methodology, not only can the reliability of fire-fighting operations be increased, but if accepted and implemented the methodology can lead to leakage reduction and improvements in water quality and the system's energy efficiency. In the test case of Novi Sad, a large number of hydrants were replaced by 14 filling stations that have been designed and constructed. A hydraulic model of the water supply network was calibrated using pressure-drop tests and flow capacity measurements of the existing hydrants. The model was used to examine the performance of the designed filling stations during their parallel operation. The paper presents the results of the test application and recommendations for the possible implementation of the concept

Exploitation of Documented Historical Floods for Achieving Better Flood Defense

Establishing Base Flood Elevation for a stream network corresponding to a big catchment is feasible by interdisciplinary approach, involving stochastic hydrology, river hydraulics, and computer aided simulations. A numerical model calibrated by historical floods has been exploited in this study. The short presentation of the catchment of the Tisza River in this paper is followed by the overview of historical floods which hit the region in the documented period of 130 years. Several well documented historical floods provided opportunity for the calibration of the chosen numerical model. Once established, the model could be used for investigation of different extreme flood scenarios and to establish the Base Flood Elevation. The calibration has shown that the coefficient of friction in case of the Tisza River is dependent both on the actual water level and on the preceding flood events. The effect of flood plain maintenance as well as the activation of six potential detention ponds on flood mitigation has been examined. Furthermore, the expected maximum water levels have also been determined for the case if the ever observed biggest 1888 flood hit the region again. The investigated cases of flood superposition highlighted the impact of tributary Maros on flood mitigation along the Tisza River