Suburban areas are subject to strong anthropogenic modifications, which can influence hydrological processes. Sewer systems, ditches, sewer overflow devices and retention basins are introduced and large surface areas are sealed off. The knowledge of accurate flow paths and watershed boundaries in these suburban areas is important for storm water management, hydrological modelling and hydrologic...

Hydrological modeling is an area where modeling has been used for a very long time. Applications range from forecasts for the hydro power industry, public safety, agriculture and environmental monitoring. Still, to the best of our knowledge, Modelica has been very little used in hydrological modeling so far. In this paper, we aim to show that the Modelica language is well suited for hydrologica...

Multi-objective evaluation of distributed hydrological models enables an analysis of prediction behaviour of individual sub-systems within a catchment. The aim of this paper is to demonstrate an application of multi-response, multisite calibration strategy for a distributed hydrological model, so that model limitations can be identified and subsequently improved. The study was carried out for c...

A two-stage formal approach to hydrological model conceptualization is described. The approach requires the definition of hydrological variables in terms of states and rates, the construction of state-rate diagrams and the definition of equations for the rates based on an indepth understanding of the related hydrological processes. It is inferred that the approach can help modellers arrive at m...

Vegetation affects water balance of the land surface by e.g. storage of precipitation water in the canopy and soil water extraction by transpiration. Therefore, it is essential to consider the role of vegetation in affecting water balance by taking into account the temporal dynamics of e.g. leaf area index, rooting depth and stomatal conductance in hydrological models. However until now, most c...

Urbanization leads to the replacement of natural areas by impervious surfaces and affects the catchment hydrological cycle with adverse environmental impacts. Low impact development tools (LID) that mimic hydrological processes of natural areas have been developed and applied to mitigate these impacts. Hydrological simulations are one possibility to evaluate the LID performance but the associat...

A methodology for programming hydrological processes into watersheds using grid-type digital elevation models (DEMs) is investigated. This methodology is based on the basic configuration of the flow directions structure in the DEM, which is stored in files where information about topological relations and other frequently used features are saved. Some basic functions for managing topological da...

The environmental requirement of the river is the amount of water to maintain natural ecological conditions and health of quality of the river water. In this study, to estimate the environmental water requirement of Karoun River, Dez, Great Karoun and Beheshtabad sub-basin (upper Karoun) using hydrological Montana method and offers based on frequency analysis of hydrological flow normally and u...

Environmental Flow Requirement (EFR) is defined as the flow that is necessary to ensure the existence of habitats in water resources systems. EFR is defined in rivers as flow index commonly. Tennant method is the most popular hydrological method in rivers and based on the historic flow data. The most common method of hydraulic rating method is the wetted perimeter method. Habitat simulation tec...