Water Resource Facilities Research Articles

Field survey for assessing seawater reverse osmosis (SWRO) applications on very small islands in Indonesia

Very small islands in Indonesia face challenges in accessing clean water due to limited space for building water resource facilities, such as reservoirs. Most of the time, the inhabitants of these islands rely on rainwater and wells, which are not sustainable sources due to drought seasons and seawater intrusion. To address this issue, Seawater Reverse Osmosis (SWRO) can be implemented in these areas where seawater is abundant. However, there may be obstacles when applying SWRO systems in such environments. This study aimed to assess the capabilities of SWRO facilities, and the obstacles involved in evaluating clean water access on very small islands. We used a combination of structured questionnaires, interviews, and direct observations on two small islands in Indonesia, Belakang Padang Island and Labu Island. On Belakang Padang Island, we interviewed the water resource manager in October 2022 and March 2023 and surveyed 61 households in the Tanjung Sari subdistrict in October 2022. On Labu Island, we interviewed the staff of the SWRO system and surveyed 35 coastal households in September 2023. On both islands, the government improved residents’ access to clean water by constructing SWRO facilities in 2016 on Belakang Padang Island and in 2021 on Labu Island. However, on Belakang Padang Island, the system was not operational when we visited on March 15, 2023. The main obstacles were slow bureaucratic processes for repairs and maintaining the operation of SWRO facilities. These problems need to be addressed before expanding the implementation of this system to other very small islands in Indonesia.

Construction of Time-series Displacement Data of Yongdam Dam Based on PSInSAR Analysis of Satellite C-band SAR Images

The increase in water-related disasters due to climate change has a significant impact on the stability of water resource facilities. The displacement of a water resource facility is one of the important indicators to evaluate the stability of the facility. In this study, the time-series displacement of the Yongdam Dam was constructed by applying the persistent scatter interferometric synthetic aperture radar (PSInSAR) technique to the Sentinel-1 C-band SAR images. A sufficient number of persistent scatterers were derived to enable local deformation monitoring of the Yongdam Dam, and the dam showed very small displacement velocity except during the heavy rainfall in August 2020. In the future, C-band SAR imagery from the water resources satellite (Next Generation Medium Satellite 5) is expected to provide accurate displacement data for water resource facilities.

Quantitative analysis and management of sustainable development of ecological water resources and digital financial system based on an intelligent algorithm

Abstract In the modern day, water is a crucial resource for advancing society and preserving ecological balance. Growth, which lessens poverty and increases equality, is often seen as inextricably linked to the effective use of water resources. Traditional water system management aims to optimize surface water and subsurface aquifers to meet conflicting needs. As a result, the special difficulties in water resource management (WRM) would be exacerbated by the added uncertainty brought on by climatic change. Managing the world's water supplies sustainably is crucial to the planet's continued existence and prosperity. However, ecological planning for sustainable water development is difficult because of complex impacts, random processes, and hydrological restrictions. The study was inspired to address the issues head-on by creating a hybrid AI algorithm for ecological water resource sustainability and digital finance (HAI-EWRS-DF) system for solving complex, multi-scale problems in WRM. Control mechanisms, including social, financial, and sustainability on ground-level and surface-level water resource facilities, are recommended to enhance WRM to increase the applicable revenue, promote community well-being, and pave the way for greater economic development.

Development of a One-Parameter New Exponential (ONE) Model for Simulating Rainfall-Runoff and Comparison with Data-Driven LSTM Model

Runoff information can be used for establishing watershed water management plans. However, hydrological models with complex parameters make it difficult to quickly estimate runoff. This study developed a one-parameter new exponential (ONE) model for simulating rainfall-runoff using a single parameter, which was designed based on a nonlinear exponential function and watershed water balance that varies according to the soil water storage. The single parameter was included in the runoff function and implemented to continuously track the state of the soil water storage based on the watershed water balance. Furthermore, to validate the model’s effectiveness, it was applied to two multipurpose dams in Korea and the results showed that the daily results of the ONE model were better than those of a learning-based long short-term memory model in terms of the quantitative evaluation indices, monthly heatmap and annual runoff rate. This study demonstrated that rainfall-runoff can be simulated using only one parameter and that minimizing the number of parameters could enhance the practical utility of a hydrological model. The use of a single parameter is expected to maximize user convenience for simulating runoff, which is essential in the operation of water resource facilities.

Comparative Study on Flora Characteristics and Species Diversity on Dam Slopes for Sustainable Ecological Management: Cases of Eight Dams in Korea

Dams are gray infrastructure, providing various benefits such as flood control, water supply, and power generation. In order to create the next generation of infrastructure that explores how nature can act as infrastructure to meet development and ecological sustainability, artificial plantings have been attempted on dam slopes in Korea since 2000. As the planted trees are now stabilized to form a forest, it is time to study the floral characteristics and functions for effective ecological management and the safety of the dams. In this study, we investigated and analyzed flora in the slopes of eight dams in Korea. The comparative study of the whole flora in both the planted zones of the slopes of dams and left and right forests of dams revealed that the number of plant species was higher in the planted zones than in the left and right forests of the same size area. The plant family containing the greatest number of species in the slopes was Asteraceae, followed by Poaceae, Fabaceae, and Rosaceae. Currently, the community structures and families in the slopes of dams exhibit the characteristics of habitats in the initial stage of vegetation succession. Our investigation of planted species and immigration species in the slopes revealed that the latter comprised 89.9%. An average of 34.4% of species were interacting with the dam slope and the left and right forests. The species diversity index on dam slopes showed a tendency to be higher as the number of planted species increased and the period time increased. Average growth heights of planted trees were identified as 0.5–1.6 m for the shrubs layer, 3.5–4.5 m for the small trees layer, and 6.0–7.2 m for the trees layer. The heights of major trees, including Pinus densiflora, Quercus spp., Prunus sargentii, Styrax japonicus, and Cornus controversa, were similar to or higher than those of their counterparts in natural forests. As a result, dam slopes were similar to natural forests, having potential as habitats for various flora. To harmoniously maintain the ecological health and safety of water resource facilities of the slopes of dams, however, it is necessary to conduct periodic and various investigations on changes of the flora and growth of trees, and actively manage them.

Using an unmanned aerial system to monitor and assess irrigation water channels susceptible to sediment deposition.

The irrigation channel of the Qishan River is among the most crucial agricultural water resource facilities in Qishan District, Kaohsiung City, Taiwan. The channel was blocked by debris due to flood events caused by Typhoon Morakot in 2009. This study analyzed images captured by an unmanned aerial system to identify channel areas susceptible to sediment deposition and propose measures for reducing the effects of natural hazards on irrigation water resources. The analysis results revealed that the channel was located downstream of the Qishan River; however, debris flows, riverbank landslides, and natural dam breaches deposited sediment in the downstream section, preventing the flow of water. Furthermore, the sediment and driftwood blocked the channel. The channel was also blocked due to a hyperconcentrated flow. Sediment deposition areas and volumes were estimated. On the basis of these results, we suggest that the damaged riverbed groundsills and river tributary banks be restored to inhibit erosion. In addition, subsurface water collection and transfer structures should be constructed to maintain the flow of water during the dry season. The study findings are expected to increase the efficiency of agricultural irrigation water management and prevent natural hazards from affecting water resources.

Legislative and policy issues related to the advancement of the maintenance system of water resource facilities

Legislative and policy issues related to the advancement of the maintenance system of water resource facilities

Optimization of water distribution of network systems using the Harris Hawks optimization algorithm (Case study: Homashahr city)

In this article applies the Harris Hawks Optimization Algorithm for optimization of the water distribution network of the Homashahr located in Iran for a period of one month (from 30 September 2018 to 30 October 2019). The utilized time-series data included water demand, reservoir storage. In this article, a model based on the Harris Hawks Optimization Algorithm (HHO) was developed for the optimization of the water distribution network. The analysis showed that the best solutions achieved by the Harris Hawks Optimization Algorithm (HHO) were 35,508 $. The results revealed that the HHO algorithm was well in the optimal design of water supply networks problem. At the end, about 12% of the optimization was done by this algorithm.•In this article applied the Harris Hawks Optimization Algorithm for optimization of the water distribution network of the Homashahr located in Iran.•The method presented in this article can be useful for managers of water and wastewater companies, water resource facilities and water distribution system managing director for optimal network design to reduce costs.•The present algorithm performs better than the other algorithms in the discussion of the optimization of water distribution networks.

Estimation of nonlinear parameters of the type 5 Muskingum model using SOS algorithm

The Symbiotic Organisms Search Algorithm (SOS) is used as an algorithm based on the social behavior of Symbiotic Organisms in optimization of Non-linear 5 model parameters for flood routing.The data used in this article is 4 day observations from 30 November 2008 to 3 December 2008, which is located between the Molasani, and Ahwaz station on the Karun River.The time series data used included river inflow, storage volume, and river outflow.The results of the developed model with the Symbiotic Organisms Search Algorithm (SOS) were compared with the other Evolutionary algorithms including Genetic Algorithm (GA, and Harmony Search Algorithm (HS).The analysis showed that the best solutions achieved from the objective function by the SOS, GA, and HS algorithms were 143052.02, 143252.35, and 142952.45, respectively. The processes of these datasets determined that the SOS algorithm was premiere to GA, and HS algorithms on the optimal flood routing river problem.•In this article applied the Symbiotic Organisms Search Algorithm for Estimation of nonlinear parameters of the Muskingum hydrologic model of the Karun River located in Iran.•This method can be useful for managers of water, and wastewater companies, water resource facilities for predicting the flood process downstream of the rivers.•The present algorithm performs better than the other algorithms in the discussion of the optimization of Nonlinear 5 parameters of Muskingum model in flood routing.

Calibration of water quality model for distribution networks using genetic algorithm, particle swarm optimization, and hybrid methods

Chlorine reacts with both organic and inorganic matters in water. That is why water quality modeling has received great attention in recent years. The serious issue in municipal water quality modeling is gathering the essential input parameters of the model, particularly bulk decay (kb) and wall decay (kw) coefficients as well as their calibrations. Therefore, this study first thoroughly formulates the problem in the form of a heuristic optimization and then utilizes Genetic Algorithm, Particle Swarm Optimization, and Hybrid GA-PSO as the model optimizers in order to best calibrate kw for minimizing the difference of residual chlorine concentrations that exist between the simulated and observed values. These three algorithms are linked to EPANET, the hydraulic and water quality simulator. The method is then applied to a real-world water distribution network. Here, kw is considered as a decision variable. The objective function is to minimize both the Sum of Square Error and Root Mean Square Error between the observed and simulated chlorine concentrations. According to the simulation results obtained, the optimal value of wall decay coefficient is 1.233 m/day during the calibration process while the minimum and maximum differences between the measured and simulated chlorine rates were 0 and 0.18, respectively.•The method presented in this article can be useful for managers of water and wastewater companies, water resources facilities and operators and operation manager of water distribution system to manage chlorine dosing rate.•Due to adverse health effect of disinfection by product and poor microbial water quality as results of inefficient chlorination, control chlorine concentration in water distribution networks and its consequence on human health effect is necessary.•Hybrid PSO and GA methods are used to cope with their falling in local optimum and requiring highly computational effort.

An evaluation on power generation of water resources facilities in North Korea considering climate change

An evaluation on power generation of water resources facilities in North Korea considering climate change

Implementation of Sustainability on Small-scale Water Resource Facilities for Developing Countries

Implementation of Sustainability on Small-scale Water Resource Facilities for Developing Countries

Awareness of STI and HIV among Indian Women: New Evidences from DLHS-4

Introduction: Sexually transmitted infections (STIs) are important cause of infertility in men and women. Some STIs increase the risk of HIV acquisition and transmission by three-fold or more. In 2011, 12% of females and 6% of males in India reportedly suffered from STIs. The total number of people living with HIV/AIDS in India was estimated at around 20.9 lakh in 2011, 39% of which were women. It is, therefore, important that population, especially women in reproductive age, should be aware of STI/RTI and HIV/AIDS. The aim of this study is to assess the awareness of STI/RTI and HIV/AIDS among ever married women in India and also to highlight their sociodemographic and economic correlates from District Level Household and Facility Survey (DLHS)-4 data. Methodology: Data from 319,695 ever married women aged 15–49 years from 21 states/UTs of India, who participated in the DLHS-4 was considered. Chi-square and multiple logistic regression analysis were performed for analysis. Results: Overall around 25% of women had heard of RTIs/STIs, whereas 66% had heard about HIV/AIDS. Adjusted analysis indicated that all the variables that were considered, viz., type of locality, caste, age, education of women and of their husbands, socioeconomic group, religion, marital status and water resource and toilet facilities used were significantly associated with awareness of STI and HIV. Conclusions: Awareness of STI and HIV is still low among women in India. Comprehensive awareness programs and interventions are needed focusing on women, who are less educated and who are economically disadvantaged.

Abe Barek landslide and landslide susceptibility assessment in Badakhshan Province, Afghanistan

Landslide is one of the most widely distributed mass movements in mountainous areas. With its wide spreading, abrupt, and seasonal characteristics, landslide always causes huge risks towards transportation, human settlements, industrial and mining plants, water resources facilities, and hydropower stations. Abe Barek landslide, which happened in the morning of May 2, 2014, in Ago District, Badakhshan Province, Afghanistan, buried 86 houses and took the lives of almost 2700 people. Many factors triggered the occurrence of this disaster. Firstly, the landslide-impacted area has a complex geologic structure that bears concentrated faults with mountain slopes covered by thick loess. Secondly, at the time of landslide, a continuous rainfall had deepened the level of moisture in the loess layer, which made the loess mass heavier and changed the soil body's mechanical properties. Thirdly, a similar landslide once happened on the same slope, which destroyed the land cover and transformed the topology of the slope. In addition, farming and irrigating activities may have also affected the stability of loess mass in this area. Upon an initial examination of landslide distribution in Badakhshan Province by using high-resolution remote sensing images from Google Earth, a total number of 609 landslide sites were identified in this area, and a landslide susceptibility assessment was completed by utilizing weight-of-evidence method. Several suggestions on landslide risk reduction in this remote mountainous area are proposed at the end of this paper.

基于基尼系数的中国水生态分区研究

PDF HTML阅读 XML下载 导出引用 引用提醒 基于基尼系数的中国水生态分区研究 DOI: 10.5846/stxb201306091529 作者: 作者单位: 中国水利水电科学研究院,水利部 水利水电规划设计总院,水利部 水利水电规划设计总院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(50709033); 中国水利水电科学研究院专项(水功能区限制纳污红线制度建设对策与措施) Establishment of aquatic ecosystem divisions based on the environmental Gini coefficient in China Author: Affiliation: China institute of water resources and hydropower research,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:提出了反映水生态系统空间分布规律和特征差异的水生态分区方案,并与国家现有的水资源分区、生态功能区划、水功能区划等相关区划成果相互衔接,为水资源综合利用、流域生态保护和经济社会发展规划提供实用的自然基础。以我国自然地理特征的空间变异与地域关联为依据,以流域为基本单元,进行水生态区划的初步研究,提出了分区的指标体系、步骤和区划方法,形成了两级的全国水生态分区体系。首先,划分为东部区、中部区、西北区和西南区4个水生态一级区;进行水生态二级区划时选取水资源量、降雨量、人口密度、NDVI作为分区的评价因子,根据洛伦茨曲线和基尼系数对分区合理性进行了检验。验证结果表明,各个水生态二级区的水资源量与降雨量、人口密度和NDVI值之间的基尼系数均不超过0.4,分区方案比较合理,从而形成34个水生态二级区,分布在东部13个,中部10个,西北6个,西南5个。 Abstract:The division scheme discussed in this study is based on the characteristics and spatial distribution of aquatic ecosystems; the scheme takes into account natural geographic features, water resources, hydrological characteristics, ecosystem functions, environmental and socio-economic conditions, and the impact of water conservancy projects on watersheds. It is based on divisions within China based on natural geography, ecological function, water resources, and water functions. This study proposes the establishment of national water eco-region divisions, including an indexing system, specific methods for establishment of divisions, and a sequence of steps for dividing water eco-regions. This study also divided watersheds nationwide into various water eco-regions, which were subsequently evaluated and verified using economic test procedures. The proposed water eco-regions would provide a viable basis for the comprehensive utilization of water resources, ecological protection, and economic and social development, for general planning of nationwide watersheds. There are three landforms extending from west to east in China, together with a dry and wet area stretching from the northwest to the southeast. Water eco-regions take into account existing physical geography, climate, water resources, and ecological conditions, as well as national ecological function zoning and water districts. From the perspective of systems analysis, we propose an indicator system that includes three layers, namely target, feature, and index layers; these provide a reflection of the spatial distribution of regional natural geographical and climatic conditions, water resources, aquatic ecosystems, human activities, the layout of economic and social structures, and ecological differences. The index layer included 11 indices; the key indicators among these for division of water eco-regions are landform, vegetation cover, and depth of annual runoff. A set of secondary indicators was used to adjust and correct the preliminary subdivisions; this included altitude, the status of aquatic systems, important protected species, the distribution of rivers and lakes, the location of reservoirs, administrative divisions, population density, and the distribution of large cities. The Gini coefficient (also known as the Lorenz factor) for economic income distribution was applied to evaluate the rationality of the proposed aquatic ecosystems division scheme. The eco-region scheme was adjusted and corrected according to evaluation results. The method took into account total water resources of each eco-region as an evaluation index, as well as rainfall, population density, and the NDVI value of each eco-region as distribution indices; these were used to verify the division schemes using the Gini coefficient and Lorenz curves. Results indicated that the division scheme was reasonable when the Gini coefficient for water resources and amount of rainfall was 0.10, when the coefficient for water resources and population density was 0.40, and when that for water resources and NDVI was 0.32. We propose a two-grade eco-region division system for national aquatic ecosystems. This includes four first-grade aquatic eco-regions, namely the east eco-region, middle eco-region, northwest eco-region, and southwest eco-region. These serve macro-economic management purposes, as well as fulfilling overall layout needs for the development and utilization of water resources and aquatic ecosystems protection. Based on water resource management and facilities for ecological protection and restoration in watersheds, 34 second-grade aquatic eco-regions are proposed, including 13 in the east eco-region, 10 in the middle eco-region, 6 in the northwest eco-region, and 5 in the southeast eco-region. The proposed national water eco-division scheme provides a scientific basis for national ecological protection and construction planning, for maintaining regional ecological security and promoting sustainable social and economic development, and for providing management information and tools for environmental management and decision-making departments. 参考文献 相似文献 引证文献

Accuracy, Security, and Architecture Impacts and Challenges of Mobile and Web Technologies: Geolocation Field Data Collection in Washington State Water Resources

The purpose of this paper is to examine accuracy, security, and architecture impacts and challenges of mobile and web technologies through the case study of collecting geolocation field data in Washington (WA) State water resources. Effective management of water as a public resource relies on the capture, storage, and retrieval of accurate geographic position data. This is also true of a broad range of business domains beyond water resources, such as earth sciences, city planning, and navigation to name a few. Application developers must choose how to capture this information (with enough accuracy to be useful for its intended application) and get that data to a place where it can be processed and used. A traditional monotonic application using a Global Positioning System (GPS) and a mobile app using a smartphone are available today. The advent of HTML 5 now allows the development of a mobile web app, which is not dependent on any particular smartphone platform. These multiple technical options lead to two research questions: How does an HTML5 mobile web app solution work in terms of accuracy, security, and architecture, compared with a GPS-based solution and a mobile native app solution for collecting geolocation field data? And second, as HTML5 mobile web apps are a relatively new technology, what best practices can we uncover to assist in the process of choosing between an HTML5 mobile web app and a mobile native app, and also what are the best practices for building a mobile web app that can operate offline? To answer these questions, we build an HTML5 mobile web app called „LocationSharpener‟ for collecting GPS locations leveraging three of the new HTML5 features: IndexedDB, AppCache, and GeoLocation. We use the mobile web app to collect locations of water resources facilities like wells and diversions and analyze how accurately the app collects the geolocation data. We apply threat risk modeling to the mobile web app to analyze its security and privacy compared to that of the native mobile app approach. In addition, by documenting the architecture of the mobile web app with multiple views, we analyze how HTML5 affects the architecture and present best practices for building a mobile web app that can operate online and offline. The analysis of location accuracy shows the HTML5 mobile web app approach provides acceptable location accuracy even when offline. Threat modeling demonstrates that, in contrast to native mobile apps, mobile web apps offer a clear advantage to users and developers: an isolated execution environment makes it more difficult for a malicious mobile web app to read private data; As an outcome of the architecture documentation we also propose new best practices of developing a mobile web app using HTML5: the developer must consider two subsystems for online and offline use cases and a sequence of connected, disconnected, and connected deployment modes. Also, standards-based web apps are portable across virtually any operating system. This also eases the burden on developers, since they can write mobile web app once and deploy anywhere.

Real-time prediction of the peak suspended sediment concentration and sediment yield of the Lao-Nung River during storms

Based on rainfall erosion of soil and suspended sediment transport in storm events, a method is proposed to predict peak suspended sediment concentration and suspended sediment yield in watersheds based on rainfall characteristics prior to peak rainfall intensity. The rainfall characteristics factors that dominate peak suspended sediment concentration C p are rainfall erosion factor R ef , first peak rainfall intensity of area-average rainfall i p 1 and antecedent precipitation index I ap ; the rainfall characteristics factors that dominate suspended sediment yield Y ss in storm events are total rainfall P, suspended sediment yield factor R sf and antecedent precipitation index I ap . This research focuses on watersheds in Liau-Kwei observation station along Lao-Nung River in southern Taiwan as the research object, and adopts the PSED-model to simulate the discharge hydrograph, suspended sediment concentration hydrograph and suspended sediment yield in 11 storm events for analysis. The analytical results show that there is a good correlation between the above-mentioned rainfall characteristics factors and C p as well as Y ss , thus enabling C p and Y ss to be predicted by using Expressions (13) and (14). These two expressions are utilized to predict C p and Y ss of Typhoon Morakot in 2009, and the results are compared with those from simulation by using the PSED-model. The result of comparison shows there is a good capability in predicting. For the watersheds where it is necessary to predict C p and Y ss of a storm event for the benefit of effective operation of water resource facilities, the aforesaid rainfall characteristics factors can be utilized to establish applicable models for prediction.

Water-resource facilities and management strategy for Oman

Catastrophic floods and prolonged periods of drought are the main ‘water’ challenges facing Oman. So the inhabitants have had to resort to ingenious ways of utilising the available-water resources, such as through building falaj systems and the optimal selection of suitable crops, but nevertheless when exposed to extremely-dry weather conditions, temporary and even permanent migration is still the only option left to some of those adversely affected. The water problem has been compounded as a result of the rapid economic development of Oman since the beginning (in 1967) of the extraction there of crude oil in commercial quantities. During this period, the general health of the population has improved, the average family-size has grown, and the mean life-expectancy has increased. Also, as the economy has prospered, the number of immigrant workers has risen to become today approximately 25% of the total population. Thus the requirement for more reliable supplies of potable water has increased substantially and is still growing. The demands placed upon natural groundwater resources (i.e. fresh-water aquifers) have become excessive: seawater intrusion has occurred into some fresh-water aquifers as a result of the over-extraction of ground water and, in others, the aquifers have simply dried up. The Government has resorted to the use of desalination technologies for producing the additional potable-water supplies needed. However, desalination is relatively expensive and energy intensive! So a programme of better water-resource management is being implemented. This has required the collection of meteorological data for many regions of Oman. It is realised that the construction of dams across the wadi watercourses, to harness flash-flood water during storms, has the potential for reducing the need for the non-sustainable over-exploitation of underground aquifers. Also the possibility of utilising images taken from Earth-orbiting satellites for the exploration for ground-water fracture-zone aquifers is being considered in order to try to locate substantial resources, which have failed to be detected by conventional drilling methods, because such water is often at great depths (exceeding 1 km).

A penalty-based optimization for reservoirs system management

A model is presented for planning the operations of interconnected surface water resource facilities equipped with hydroelectric power stations. These facilities are operated for the purpose of water supply, hydroelectric power generation and low flow augmentation for navigation purpose. The model is formulated as a deterministic large-scale nonlinear program, with decision variables being the monthly reservoir releases, and canal and pipeline flows through turbines. A solution procedure is proposed based on penalty method in which the nonlinear constraints are assigned penalty weights and moved to the objective function. The resulting problem with linear constraints is solved using reduced gradient techniques. The calculations of the reduced gradient is carried out efficiently by utilizing the special structure of the matrix involved in the linear equality constraints. The results of this procedure are compared against those obtained using a subgradient optimization algorithm. The method has been validated using a five-reservoir system of the Senegal River Basin in West Africa, where it serves as the model-base of the planning decision support system.

Impact of changing computer technology on hydrologic and water resource modeling

The increasing availability of substantial computer power at relatively low costs and the increasing ease of using computer graphics, of communicating with other computers and data bases, and of programming using high‐level problem‐oriented computer languages, is providing new opportunities and challenges for those developing and using hydrologic and water resources models. This paper reviews some of the progress made towards the development and application of computer support systems designed to aid those involved in analyzing hydrologic data and in operating, managing, or planning water resource facilities. Such systems of hardware and software are being designed to allow direct and easy access to a broad and heterogeneous group of users. These systems often combine data‐base management; simulation and optimization techniques; symbolic colored displays; heuristic, qualitative approaches; and possibly artificial intelligence methods in an interactive, user‐controlled, easily accessible interface. Individuals involved in the use of such systems are not only those with technical training, but also those representing different interest groups and having non‐technical backgrounds. The essential difference between what is happening now and the more traditional off‐line, non‐interactive approaches is that instead of generating solutions to specific problems, model developers are now beginning to deliver, in a much more useful and user‐friendly form, computer‐based turnkey systems for exploring, analyzing and synthesizing plans or policies. Such tools permit the user to evaluate alternative solutions based on his or her own objectives and subjective judgments in an interactive learning and decision‐making process.