The paper deals with calibration of the simulation models of hydraulic part of an irrigation project. Calibrated simulation model can be used in design, reconstruction, enlargement or maintenance of the pressurized irrigation systems. Computer model of the water distribution system is a valuable tool which can assist engineers and planners in analyzing the hydraulic performance of water delivery systems. Calibration of the water distribution model consists in comparison of pressures and flows predicted with observed pressures and flows for known operating conditions (i.e., pump operation, tank levels, pressure-reducing valve settings), and adjustment of the input data for the model to improve agreement between observed and predicted values. In practice, given a set or sets of measured state variables, engineers apply trial and error techniques with their judgment to vary the parameters and accomplish this task. Trial and error techniques are tedious do not guarantee reasonable results. The paper introduces the methodology of determination of calibrated parameters automatically. Described methodology of calibration is based on optimizing procedures using the harmony search approach.
The abundance of water has certainly been a very important resource for the development of the Po Valley and has necessitated, more than once, interventions of regulation and drainage that have contributed strongly to imprint a particular conformation on the land. Already in Roman times there were numerous projects of canalisation and intense and diligent commitment to the maintenance of the canals, used for navigation, for irrigation and for the working of the mills. The need to control the excessive amount of water present was the beginning of the exploitation of this great font of richness that was constantly maintained in subsequent eras. In the early Middle Ages, despite the conditions of political instability and great economic and social difficulty, the function of the canals continued to be of great importance, also because the paths of river communication often substituted land roads, then left abandoned. After the 11th century A.D. the resumption of agricultural activity was conducive to the intense task of land reclamation of the Lombardian countryside and of commitment by the cities to amplify their waterways with the construction of new canals and the improvement of those already existing. The example given by Milan, a city lacking a natural river, that equipped itself with a dense network of canal, used in various ambits of the city life (defence, hygiene, agriculture, transport, milling systems) and for connections with the surrounding territory, can be considered as emblematic. In the surrounding countryside, the activity of the Cistercian monks of Chiaravalle represents one of the situations more indicative of how land reclamation and waterways contributed fundamentally to the organisation of the territory over the span of the ages.
The irrigation system control is identified as a complex hierarchical process of stochastic nature, at the head of which the uncertainties, caused by random variations of meteorological factors (climate) and diversion capacity regime from irrigation canals, were laid.
Under such conditions application of the determinate methods for irrigation system control regarding the effectiveness surrenders to the formalistic and empirical methods.
The most appropriate method is the developed by us, method of preventive control.
As a result of retrospective analysis, to each system status, for example, diversion capacity, it is fixed the factors which lead to its changes, for example, rain layer or total evaporation. To every consequence “factor – system status” it is fixed the indicator and it is determined the probability of its exceeding in retrospective series.
The control is in following of such indicator dynamics, forecasting of the most probably changes within system status and adjustment of the water delivery regime to canal reaches with diversion capacity regime from irrigation canals by means of standard preventive graphical chats of water flow control within hydraulic structures and pumping stations.
Use of such control method allows to minimize the uncertainty influence, also it does not require the major modifications in the design and engineering infrastructure.
As an exception can be the measures, directed to the increase of self-regulating qualities of irrigation systems, namely the ability of on-line water volume control, which is regulated in the idle capacities, provided in canal beds or special reservoirs.
The example of such decision in practice is the Kakhovskaya irrigation system in the South of Ukraine. The use factor of water resources on this system reaches 0.85, the technological discharge water does not exceed 7%, the deficit of productive moisture reserve in soil at the end of interirrigation period does not exceed 20% and all these data were obtained under adverse weather conditions.
Canal connecting Elbląg with Ostróda was built in the XIX century to transport corn to the port of Elbląg. Due to economic and political changes it never played its economic function. Now it is a tourist attraction. The canal is thus of some tourist value which is difficult to assess. Tourist value of the Elbląg Canal was assessed with the travel cost method (TCM) within the study carried out in 2003. The study allowed for estimating the object’s value based on its usefulness expressed by inclination to payment. Three groups of users were distinguished when analysing the demand for recreational canal’s services: tourists using ships of the Elbląg–Ostróda Navigation Company, individual sailors and anglers. Total tourist value of the canal calculated as NPV of the annual value of canal’s services depends on adopted interest rate. At a rate of 3.2% the value is 328 thous. PLN (73.9 thous. euro), at a rate of 4% – 282 thous. PLN (63.5 thous. euro), while at 8% interest rate it decreases to 160 thous. PLN (36.0 thous. euro).
Many of already existing roads cross wetland river valleys. Also the roads nowadays planned are cutting through valuable wetlands. It is necessary to evaluate the range of their impact on the natural environment. This paper focuses only on the analysis of the road crossing impact on the groundwater level. Two options of crossing the wetlands were analyzed, building the road on embankments and in the bridge. It was assumed that the valley is filled with organic material under laid by permeable sands. Calculation results showed that building a road in the valley affects groundwater level only to the slight extend. Water conditions in the valley may be affected only during the construction of the road. Calculation results were confirmed by field observations.
It should be stressed that the object of this paper is the evaluation of water conditions. Environment might be influenced by other factors.
The research was set up in the Neretva River valley in the Southern part of Croatian Karst area, where implementation of modern hydrotechnical practices within the river catchment’s area led to intrusion of seawater to groundwater resulting in soil salinization in the delta. The region has great agro-ecological potential for intensive production of vegetables and Mediterranean fruits. Since the combination of the effects of saline groundwater and the use of this water for irrigation may have disastrous effects on the productivity of agricultural soils water, a project was started in order to set up a permanent monitoring network. The aim of this study was to determine the salt dynamics in the surface water on five locations which are considered as potential sources of the irrigation water (Modric canal, Neretva River near Opuzen, Crepina, Jasenska and Vidrice pumping station) during a 4-year period (1999–2002). The surface water samples had been collected on monthly basis and analyzed for all parameters required in the irrigation water quality classification. The results show considerable spatial and temporal variability of determined parameters. Thus, in the Neretva River near Opuzen, total salt concentrations in water ranged from 0.4 to 7.7 dS·m–1, and in Modric from 1.65 up to17.2 dS·m–1. Dominant cations and anions on all observed locations were Na+ and Cl–. Constantly high concentration of Na+ in sampled surface waters is of a special concern. Utilization of the water of such quality may cause problems related to the use of alkaline waters for irrigation, which can further cause permanent loss of fertile soil.
Two-third of the area of the Netherlands is flood prone. Storm surges at the North Sea, floods in the rivers, failure of secondary dikes, as well as heavy rainfall may cause flooding. Most of the flood prone areas rely for their existence on drainage by pumping, because their surface level may be permanently or during floods up to several metres below the surrounding water levels. During the past decades climate change is generally felt as a reason for major concern. However, the impacts of climate change on increase in extreme conditions may be up to 45% per century. If we look at the man-induced changes in land use, due to increase in population and rapid increase in the value of public and private property, then one may observe an increase of 100–1,000% per century. One should therefore wonder what would have to be our major concern.
In the paper the relevant processes are described, based on some characteristic data on water management and flood protection in the Netherlands. It is shown that impacts of climate change on water management and flood protection may be expected, but that such impacts can easily be accommodated during improvement works on water management systems and flood protection provisions that from time to time will be required. It will be much more important to take carefully into account the risk of flooding in the planning of land use development, especially for valuable types of land use like urban and industrial areas, green houses and recreation areas.
Irrigation in Croatia was until recently a neglected measure in food production, especially in continental part of the country. Development of drainage system in the last fifty years was more important due to the problems caused by floods and excess water in the fields. In the last decade the hydrological regime has been changed and drought events became as frequent as flood events, causing even more damage. Future development of agriculture in the northern counties of Croatia depends on the introduction of new, profitable crops which imply irrigation as an essential factor of future social and economic growth.
The first step in the implementation of irrigation was the development of National Irrigation Master
Plan as a framework for future activities.
According to the recommendations of the National Master Plan all counties have created County Irrigation Plans considering local natural conditions, social and economic background.
This paper is going to present how is that process of integrated water resources management developing in the continental part of Croatia on the example of Osijek County Irrigation Plan located in the Danube river basin.
Lublin Upland and Roztocze region are known for the occurrence of a large number of springs of high yield. These springs are fed mainly from Cretaceous or Tertiary water-bearing horizon. In order to determine variability of springs’ yield, 61 selected springs were analysed in spring periods of the years 1998–2008. Collected hydrometric materials allowed for comparing average and extreme yield values of springs in various physiographic regions within the period of 11 years. Average value was 76.1 dm3·s–1, while the mean of the minimal yields was 44.7 dm3·s–1 and of the maximal – 132.7 dm3·s–1. Coefficient of irregularity of the springs’ yield ranged from 1.5 to 5.0, which may lead to the conclusion that the springs’ yield is constant or varies slightly. In some cases the irregularity was higher but it was determined by hydrogeological, meteorological and local factors.
Nutrient emissions by point and diffuse sources and their loads were estimated for the Odra catchment over the time period of the last 50 years by means of the model MONERIS. For nitrogen a change of the total emissions from 38 kt·a–1 N in the mid of 1950s a maximum of 105 kt·a–1 N in the early 1980s and a recent value of about 84 kt·a–1 N were estimated for the total Odra Basin. The share of the point source discharges on the total N emissions varied between 24% (1955) and 35% (1995). The emissions from groundwater and tile drained areas represent the dominant pathway (37–56% of total N emissions) during all investigated time periods. Emissions from tile drained areas increased from the mid of 1950s to end of 1980s by a factor of 20 and reached in this period the same amount as emissions by groundwater. For phosphorus the emissions changed from 4 kt·a–1 P in 1955 to 14 kt·a–1 P in 1990 and a recent level of 7 kt·a–1 P. Point source discharges caused between 36 to 66% of total P emissions and represent the dominant pathway for all investigated time periods. Erosion and discharges from paved urban areas and sewer systems was the dominant diffuse pathway of the total P emissions into the river system. The comparison of calculated and observed nutrient loads for the main monitoring stations along the Odra River shows that the average deviation is 12% for total phosphorus (1980–2000) and 15% for dissolved inorganic nitrogen (1960–2000). From the analysis it can be concluded that the present load of dissolved inorganic nitrogen (DIN) and total nitrogen (TN) of the Odra into the Baltic Sea is about 2.3 times higher than in the mid of 1960s. The maximum DIN load (1980s) was more than 3 times higher than in the 1960s. The change of the total phosphorus (TP) load is characterized by an increase from the 1955s to 1980 from 2 to 7 kt·a–1 P (factor 2.6). Around 2000 the TP load was 4 kt·a–1 which is only the double of the level of the 1955s
Along the paper the new method called Invertebrate Bankfull Assessment method (IBA method) of determination of bankfull discharge is presented. The investigation of bankfull discharge using IBA were performed within one Polish Carpathian stream in the mountain region: the Ochotnica Stream. As an index of bankfull the existence of certain species of invertebrates was used which are present and resistant to specific water discharge conditions. The borders within a cross section of the mountain stream with a gravel bed were defined where characteristic invertebrates are present which are recognized as bankfull borders. Finally three invertebrates benches (IB-ms) were recognized which are characterized by very specific invertebrate species. Bankfull discharge was calculated up to this IB-ms and corelated using Canonical Correspondence Analysis with other values of bankfull calculated for a cross section using different bankfull.
An increase of water retention in the programmes of small retention in the country to the year 2015 is estimated at 1141 million m3. It means annual mean increase of retention capacity by c. 60 million m3. Accomplishment of relevant actions in the years 1997–2007 allowed collecting 57 million m3 in lakes, c. 56 million m3 in artificial reservoirs, 18.5 million m3 in fishponds, c. 10.5 million m3 with the channel retention and over 2 million m3 in other investments. It makes total increase of water retention by 142 million m3 which is 12.4% of target retention and the mean annual increment of c. 13 million m3. The paper presents volumes of retained water, sources and structure of financing, mean unit costs of retention increments and the increase of retention capacity in particular voivodships (acc. to new administration division) in the years 1998–2007.