Stream Order Research Articles

Sediment and phosphorus contributions from eroding banks in a large intensively managed watershed in western Iowa, United States

AbstractIn this study, a new remote sensing tool was used in conjunction with sampling of river bank sediments to map channel migration patterns and estimate the net contribution of bank erosion to the sediment and phosphorus (P) budget of the Nishnabotna River in southwestern Iowa. Between the years 2009 and 2018, we found that at least 1.81 ± 0.57 × 107 Mg of sediment and 8.26 ± 2.5 × 103 Mg of P entered the Nishnabotna River due to channel migration. This equates to 0.87 Mg of sediment per meter of channel per year and 0.40 kg of P per meter of channel per year. Barring additional deposition elsewhere in the river corridor, these values represent as much as 77% of annual suspended sediment and 46% of the annual P export from the watershed. Our results also indicate that the contribution of net sediment and P volume loss by stream order increases sharply from third to sixth order, even though the total channel length is much smaller in the higher orders. These results suggest that bank erosion is an important source of sediment and P within the watershed and that future attempts to decrease riparian exports of sediment and P should focus on high‐order reaches.

River reach-level machine learning estimation of nutrient concentrations in Great Britain

Nitrogen (N) and phosphorus (P) are essential nutrients necessary for plant growth and support life in aquatic ecosystems. However, excessive N and P can lead to algal blooms that deplete oxygen and lead to fish death and the release of toxins that are harmful to humans. Estimates of N and P levels in rivers are typically calculated at station or grid (>1 km) scale; therefore, it is difficult to visualise the evolution of water quality as water travels downstream. Using a high-resolution reach-scale river network and associating each reach with land cover fractions and catchment descriptors, we trained random forest models on aggregated data (2010–2020) from the Environmental Agency Open Water Quality Data Archive for 2,343 stations to predict long-term nitrate and orthophosphate concentrations at each river reach in Great Britain (GB). We separated the model training and predictions for different seasons to investigate the potential difference in feature importance. Our model predicted concentrations with an average testing coefficient of determination (R2) of 0.71 for nitrate and 0.58 for orthophosphate using 5-fold cross-validation. Our model showed slightly better performance for higher Strahler stream orders, highlighting the challenges of making predictions in small streams. Our results revealed that arable and horticultural land use is the strongest and most reliable predictor for nitrate, while floodplain extents and standard percentage runoff are stronger predictors for orthophosphate. Nationally, higher orthophosphate concentrations were observed in urbanised areas. This study shows how combining a river network model with machine learning can easily provide a river network understanding of the spatial distribution of water quality levels.

INVESTIGATION OF DRAINAGE IN URBAN AREA USING GEOGRAPHIC INFORMATION SYSTEM IN THE CASE OF NEKEMTE TOWN

Drainage is an important aspect of the urban, rural, forest, and agricultural environments as it aids in the removal of excess water volume. In Nekemte town, where this study is conducted, different drainage problems are encountered in different places. Most drainage structures built in this area were built without a thorough drainage investigation, causing a slew of issues for the people who lived there, particularly during the rainy season. The problems that increase the drainage problems from time to time in Nekemte town were caused by the illegal use of drainage structures (components) like pipes, culverts, and ditches, and their consequence is the overflow of water because of illegal waste (solid waste) in the drainage lines. The objective of this study was to investigate drainage problems using ArcGIS software in the case of Nekemte town. To achieve this objective, a digital elevation model of the area was created from contours. Different hydrological patterns were developed using the ArcGIS hydrology tool and combined with other tools to identify cross-drainage requirements. In the study area, there are ten (10) watersheds and an outlet (pour point). Three (3) stream orders exist in the study area. Protected areas are those that are at least fifty (50) meters from the stream network. The watershed, road (current and proposed), low drainage density, and stream order are all considered when calculating an area’s cross-drainage requirement. In the study zone, there are cross-drainage requirements in twenty (20) different places. Seventeen (17) of those cross-drainages lead to exits in the protected zone. The discharge of the area is also computed using the rational method. In general, this study found that cross drainage between Wollega and the stadium is inadequate and improperly placed.

Insights of dam site selection for rainwater harvesting using GIS: A case study in the Al- Qalamoun Basin, Syria

Today's world is plagued with water shortages, especially in developing countries. The problem is made worse by increasing water demands and decreasing rainfall occurrences in arid and semi-arid areas. Rainwater harvesting (RWH) has the potential to be a viable solution for this issue, as it can augment existing water supplies in the long term. This study aimed to identify suitable areas for RWH using a multi-criteria decision analysis (MCDA) based on the analytic hierarchy process (AHP) method, combined with geographic information system (GIS) and remote sensing (RS) techniques. This study has been carried out in the Al-Qalamoun Basin, the western part of Syria, which has not been studied for rainwater harvesting before. To fill this gap, a potential RWH map was created in the Al-Qalamoun Basin using nine factors, which are land use and land cover (LULC), soil texture, slope, rainfall, curve number (CN), stream order, distance to faults, distance to roads, and distance to residential areas. All thematic layers were allocated appropriate weights and combined using the weighted Overlay process (WOP) in ArcGIS 10.8 to produce a RWH map of the study area. The findings indicated that about 18.1% of the total study area was classified as most suitable and suitable for RWH. Validation of the RWH map with the existing dams indicated that the methodology adopted in this study had a high capacity to identify sites suitable for RWH. The study presents a useful and inexpensive tool for decision-makers to avoid unsuitable sites and focus on the most suitable sites for constructing dams.

Morphometric Analysis of Tectonically Active Bhimtal-Naukuchiatal Lake Basin, Kumaun Himalaya

Bhimtal-Naukuchiatal region, which is an integral part of the Kumaun Lesser Himalaya, is sensitive to natural disasters and has a fragile environment as a result of neotectonic activity along the thrust and secondary thrust/faults. With regard to neotectonic activity, this study aims to comprehend the tectonic instability of the basin. Morphometric analysis is a computable research of landforms that is crucial to understanding how the landscape has evolved in response to nearby tectonic activity. In present exercise we have calculated ten morphometric indices, viz., Valley floor width-height ratio (Vf), Hypsometric Integral (HI), Stream-Length gradient Index (SL), Bifurcation ratio (Rb), Drainage density (Dd), Stream Order (Sµ) and average Sinuosity (S), Relief (H), steepness (Ksn), Chi integral (?) and Asymmetric Factor (AF). The result shows low values of Vf indicate high upliftment rate, more incision and less channel down cutting. Most morphometric results suggest tilted basin, resulting in V-shaped valleys and a distorted and unstable longitudinal profile, which indicate the area is governed by both tectonics and lithology. The field geomorphic features along with the software based calculations suggest that the Bhowali-Bhimtal-Naukuchiatal is tectonically active zone.

Characteristics of the watershed and their implications for the hydrological response to water in the Nafit basin, East Iraq, Using Spatial Information Technology

It has been proven that spatial information technology, ie GIS, and remote sensing are an effective tool in the identification and planning of drainage pattern and management and planning of water resources. GIS and image processing were adopted to determine morphological characteristics and analyze them in the Nafit river basin in Diyala Governorate, east Iraq and western Iran. The basin morphometric parameters such as linear, aerial and relief aspects of the river basin were determined and computed using ArcGIS v. 10.3software. Stream orders in the basin affected to the conditions of rock structures and physiographies conditions. The study area is covered by (Fatha Formation, Injana Formation, Mukdadiya Formation and Quaternary deposits) with the area (3723km2). It is 6th order drainage basin and drainage pattern mainly in sub dendritic to dendritic type. The hydrological characteristics of the basin are influenced by the type and composition of the rocks and the amounts of rainfall.

Locating flood susceptible areas in Sabah Al-Ahmed city, Kuwait

In Kuwait, about 111 ​mm of heavy rainfall occurred overnight in 6 ​hours on the 6th of November, 2018, caused flash floods in several areas. This study deals with the preparation of flood risk maps for Sabah Al Ahmed city by using the digital elevation model (DEM) and geographic information system (GIS) tools. Secondly, the detection of areas at risk from flash floods was done using the hydrological method. Using hydrological methods of GIS tools, the present work started with fill, flow direction, flow accumulation, basin, stream link, stream order, and stream density. In addition, quantitative descriptions of watershed morphology were used, such as the length/width ratio which was 2.64, indicating that the watershed was slightly rounded. The form factor was calculated at 0.37, indicating an inconsistent shape. The relief ratio was 0.03, indicating it was low relief. As a result, the most detected channels were the seventh, sixth, and fifth stream orders. In addition, the stream morphological equations yielded a texture ratio of 48.6 ​km, indicating a smooth texture. The bifurcation ratio was 3.12, indicating that the surface runoff had a high velocity. Also, the drainage density was 3.7 ​km/km2, and the stream frequency was 7.2 streams/km2. The watershed had moderate texture. Finally, the flood risk map showed that the study area was a very high-risk area with 1.1% of the watershed. The GIS was used in a flood risk analysis due to the potential risk it posed on people, buildings, and infrastructure in the affected areas.

Development of a general protocol for rapid response research on water quality disturbances and its application for monitoring the largest wildfire recorded in New Mexico, USA

Anthropogenic and natural disasters (e.g., wildfires, oil spills, mine spills, sewage treatment facilities) cause water quality disturbances in fluvial networks. These disturbances are highly unpredictable in space-time, with the potential to propagate through multiple stream orders and impact human and environmental health over days to years. Due to challenges in monitoring and studying these events, we need methods to strategize the deployment of rapid response research teams on demand. Rapid response research has the potential to close the gap in available water quality data and process understanding through time-sensitive data collection efforts. This manuscript presents a protocol that can guide researchers in preparing for and researching water quality disturbance events. We tested and refined the protocol by assessing the longitudinal propagation of water quality disturbances from the 2022 Hermit's Peak—Calf Canyon, NM, USA, the largest in the state's recorded history. Our rapid response research allowed us to collect high-resolution water quality data with semi-continuous sensors and synoptic grab sampling. The data collected have been used for traditional peer-reviewed publications and pragmatically to inform water utilities, restoration, and outreach programs.

Implementation of space imageries, remote sensing and GIS techniques in the geological and geomorphological analysis of Wadi Fatima drainage basin, Saudi Arabia

This research aims to apply various digital image processing methods of satellite imageries and remote sensing techniques in the geological and geomorphological analysis of Wadi Fatima area, Saudi Arabia. This area includes a sequence of volcano-sedimentary rocks of Arabian Shield and it is characterized by diagnostic drainage lines. Landsat-7 images and digital elevation model (DEM) in a 30 m resolution data have been used in this work. These data were also used in the geological interpretations, extracting morphometric parameters, and geomorphological analysis of Wadi Fatima drainage basin.The geological map of Wadi Fatima drainage basin was constructed and interpreted from the processed Landsat ETM + space imageries. The structural lineaments map of Wadi Fatima drainage basin was extracted from the digital data of panchromatic Landsat ETM + band. The geomorphological analysis identified, delineated and gave the main geomorphic characteristics of Wadi Fatima drainage basin. The statistical analysis of structural lineaments and the stream orders of Wadi Fatima basin showing that the main directional trends of both have a common trend in the directions of NE-SW, N-S & E-W. This means that the main wadies of Wadi Fatima drainage basin are structurally controlled and follow up the main faults and shear zones in the area. This study results in accurate delineation and constructive detailed geological and geomorphological aspect maps of Wadi Fatima basin. Wadi Fatima basin is less dangerous due to its rectangular shape than the circular shape, because the top of the flood reaches after a long time.

A Geographic Information System (GIS) based approach for drainage and morphometric characterization of Beki river basin, India

Geographic Information Systems and remote sensing, have proved to be efficient tools in delineation of drainage pattern and different geometric methodology of geomorphologic, watershed management even GIS has been widely used in several flood management, and environmental applications. The river Beki with an area of 19,354.35 sq.km2 originates at Himalayan glacier (Kula Kangri glacier in Bhutan) 26.18° N latitudes and 90.53° E longitudes and flows though the plains of Assam and finally to the mighty Brahmaputra at 26.48° N latitudes and 91.02° E longitudes has been selected for detailed morphometric analysis. Morphometric parameters via; Stream order, Stream length, Bifurcation ratio, Drainage density, Drainage frequency, Drainage texture, Form factor, Circularity ratio, Elongation ratio and Compactness ratio etc. were measured for prioritization and compound parameter values were calculated. This study will help the local people to utilize the resources in right manner for Sustainable Water Resource Development of the Basin area. Moreover, the study can also be referred as a benchmark for studies on temporal change in geomorphology due to climate change. Different Morphometric analysis provides the explanation of physical characteristics of the watershed which are useful for the areas of land use planning, soil conservation, terrain elevation and soil erosion.

Morphometric Determination and Digital Geological Mapping by RS and GIS Techniques in Aseer–Jazan Contact, Southwest Saudi Arabia

The hydrological characteristics of the watershed in the southern Aseer and northern Jazan regions of Saudi Arabia (SA) were identified by integrated remote sensing (RS) and geographic information system (GIS) techniques using Shuttle Radar Topography Mission (SRTM) and Landsat data. For this purpose, the Wadi Ishran, Wadi Baysh, Wadi Itwad, Wadi Tabab, and Wadi Bayd drainage basins were extracted. Wadi Ishran is the largest, and Wadi Tabab is the smallest. Stream order and bifurcation ratio show that the Itwad and Bayd basins are permeable and of high aquifer potentiality. The multisupervised classification found seven rock units that were spread out in different ways across the basins. The areas with the highest vegetation were in the southeast, the centre, and the northwest. The bands’ ratios show more iron-rich sediments in the northeast and southwest. This paper’s outcomes serve as the basis for planning and managing groundwater resources. It finds potential groundwater zones, determines the risk of flooding, and chooses places where harvesting can be undertaken.

GIS based NRCS-CN modeling of rainfall-runoff in river Thamirabarani sub-basin, Southern India

River Thamirabarani sub-basin lies in the southern part of the Western Ghats in the Kanyakumari district of Tamil Nadu, India. The basin’s landforms are formed by swift surficial characteristics with undulated terrains composed of steep-sloped valleys, valley fills, and short-length streams with intensive flows that makes-up site-specific hydro-morphological characteristics. In this study, the GIS-based Natural Resource Conservation Service-Curve Number (NRCS-CN) model is used to assess rainfall-induced runoff by analyzing various hydrological parameters. The curve number (CN) is assigned to each hydrologic soil group (HSGs) based on the measurement of initial abstraction (Ia) and potential maximum retention (S) derived from soils, landuse/ land cover, antecedent soil moisture, etc. The resulting map shows the estimated runoff at the rate of 2.27 – 5.94 mm/m2/yr for the whole study area, whereas the higher runoff rate (4.83 – 5.94 mm/m2/yr) is noted in the upland range of the swift surficial terrains in the north and north-eastern parts that encompasses undulated structural hills, steep-sloped valleys, inselberg, and denudational hills, etc., whereas the work of swift surficial terrains and associated slope gradient of the landforms are considered to be higher runoff rate than the other parts. The moderate runoff rate (2.92 – 3.98 mm/m2/yr) is estimated in the middle parts of pediplains that consist of croplands, plantations, riverbanks, fallows, and built-up areas. Significantly, the lower runoff rate (<2.92 mm/m2/yr) sparsely occurred in the different landforms of the middle and southern parts that include pediplains, riverbanks, natural vegetative covers, valley-filled sediment deposits, etc. Overall results indicate that the higher runoff found over the swift surficial landforms in the north and north-eastern parts due to intensive flow through short-length stream orders. This study is mainly used for understanding hydro-morphological processes and their impacts on basin environments.

Study on Drainage Network Pattern and Morphometric Analysis by Using Hydrology Support Algorithm

Abstract The degree of accuracy in the extraction of the drainage network and morphometric analysis of the basin plays a vital role in assessing geomorphological characteristics and hydrological processes. The extraction of the exact flow network from SRTM-DEM quantifies the drainage network, and morphometric parameters, which is the main objective of this study. The Thamirabarani river basin in Tamil Nadu, India is taken as the study area. The stream order threshold algorithm is used for stream rasterization to get the pattern of the basin’s drainage network. The hydrology-based algorithm uses a different range of threshold values to determine the stream pattern, which is comparable to the stream vectors of the toposheet. The drainage network distribution with a threshold value of 10000 gives many minor streams which imply dissimilarities with the stream network of toposheet, whereas the threshold value of 20000 shows remarkable similarity to an existing river system. The model with threshold 20000 provides a Stranhler-based drainage network with a basin area of 5664.52 km2. The basin is the fifth-order stream network with many lower-order streams. The drainage pattern is resulted in dendritic and sub-dendritic. The morphometric parameters of the basin are evaluated with the help of an aspect, slope, and contour. The slope of the study area is flat in the east and steeper in the west, along the area of Western Ghats. A bifurcation ratio ranges from 1.05 to 2.42, indicating that the drainage network is not influenced by structural disturbances in that area. The comprehensive evaluation of flow patterns along with morphometric properties obtained from this study provides data support for estimation of the volume of water in the basin, reservoir operation, and construction of hydrological structures. Also, this result can be used to compute watershed attributes normally used in hydrologic and water resources studies. The hydrology-based algorithm can be employed in other river basins to extract drainage network patterns.

Hydro-Morphometric Characters of Watershed Heshkaro River in Duhok City, Kurdistan Region, Northern Iraq Using Geospatial Techniques

Hydro-Morphometric analysis of the drainage systems is an efficient tool to manage water resources to protect from flooding or discover suitable locations for hydrological projects. This study aims to analyze the morphological and hydrologic processes of the Heshkaro River watershed using Remote Sensing and Geographic Information System techniques. The river causes damage to neighborhoods, which are located at the mouth during the rainy season. The ALOS PALSAR digital elevation model (12.5 m resolution) data and ArcGIS 10.8 toolbox were used to delineate the watershed and calculate the morphometric characteristics of the river drainage. The results show that the Heshkaro River basin is a fifth-order basin with 359 tributaries and a total length reached 214.13 km, where there is a strong exponential relationship (R2 =0.97) between the mean length of streams and stream order. In addition, the study area is an elongated shape, depending on the elongation and circularity ratio. Furthermore, the bifurcation ratio, basin relief, and slope degree indicate that the geological structure has little influence on the drainage pattern. The basin has low runoff, low relief, and high infiltration, as well as low exposure to erosion and sediment loading. The results of this study provide the requirement for deep management of the Heshkaro River watershed to secure the environmental sustainability of the basin.

Evaluating geo-hydrological environs through morphometric aspects using geospatial techniques: A case study of Kashang Khad watershed in the Middle Himalayas, India

The present study analyzes the geo-hydrological behaviour of the Kashang khad basin of the satluj river system in Kinnaur district, Himachal Pradesh. The major source of water in the region is the snowmelt, which contributes to the evolution of a drainage pattern. It highlights the importance of ASTER GDEM and satellite images for assessing and understanding the various geo-hydrological parameters such as drainage analysis, and topographic analysis for better basin management. Hydrological modelling of ArcGIS 10.5 has been used for the delineation and analysis of basins using SRTM DEM with 30 m resolution. Morphometric parameters like linear, relief, and aerial further help in the micro-level study of its physiographic characteristics and structural control of flow along with runoff, which can help predict floods, their extent, and intensity. It was found that the basin had a dendritic pattern with uniform lithology. The stream order ranges from 1st order to 5th order signalling homogeneity in texture and medium to high drainage density meaning permeable soil and good surface runoff. The drainage texture of 2.19 indicates the basin is prone to weathering and erosion. The bifurcation ratio ranges from 4.43 to 5.23, with a mean Rb of 4.82 showing the structural control on the elongated basin with Re of 0.56. The ASTER DEM and sophisticated morphometric attributes and hydrological environs can be effectively utilized in watershed management and other hydrological studies in higher mountainous regions.

Rectangular drainage pattern of a submarine canyon controlled by extensional tectonic structures: Case study of the Afam Incision Surface (Tortonian, Niger Delta, Nigeria)

Submarine canyons are a key element of the growth of continental margin depocentres such as the Niger Delta, the progradation of which is commonly influenced by syn-sedimentary processes of gravity-driven tectonism. In such setting, canyons commonly constitute combined stratigraphic-structural traps because of: (i) their clayey infilling and, (ii) the incision of marine reservoirs. Nevertheless, most of the time, their drainage network and/or the external factors leading to their formation are poorly characterized, which is also the case in other settings when the resolution of geophysical dataset is less accurate. Here we use 3D seismic reflection data from the onshore eastern Niger Delta to study the morphology of a buried canyon system in relation to extensional tectonic structures, which are E-W trending growth-faults and roll-over anticlines. We map the Afam Incision Surface (AIS), which cuts up to 1000 m into subjacent Eocene-Miocene deltaic and continental series. In planform, the AIS is organized in 6 stream orders. The Afam Canyon which has the highest stream order is globally NNW-SSE oriented and is locally controlled by E-W oriented grabens, which give it right-angle changes of direction. It perpendicularly captures 5th and 4th order tributaries, each of which has an asymmetric cross-sectional profile controlled by one major growth-fault. In the southern area, the western tributaries all include an upstream part that drains in the opposite direction to the regional slope, leading to bayonet-shaped paths in planform. Whatever the stream order of the tributary considered; its increase is controlled by growth-faults. Therefore, the AIS planform network has the characteristics of a rectangular pattern. Erosion of the AIS as a submarine canyon system is consistent with its more than one-kilometer depth, preserved knickpoints within the thalweg of the main canyon; and the many erosional terraces boarded by arcuate scarps located along the main canyon and its tributaries. The formation of the AIS is correlated to the 50 m Tor2 sea-level fall at 9.5–9.2 my, and may have been initiated by by-pass currents that acted in tandem with retrogressive erosion. The latter greatly contributed to deepening and widening of the canyon and its tributaries whatever the orientation of the local slope. Erosion of the AIS was favored by the high-density of growth-faults. During the final excavation phases, the channelization of longshore drift currents by the canyon and its tributaries probably contributed to the destabilization of their upper margins.

Spatio-temporal sensitivity analysis of the wetland modules of a semi-distributed hydrological model

Hydrological models offer the opportunity to evaluate wetland conservation networks as nature-based solutions to mitigate hydrological extremes. To optimize the replication of a hydrological model response (i.e., stream flows), the models rely on input data (land cover, hydrographic network, soil types, topography, meteorological data) and parameters. However, the effect of parametric uncertainty on the simulated variables and the spatio-temporal variability of this sensitivity are insufficiently documented. This study presents an application of the novel global sensitivity analysis method, the Variogram Analysis of Response Surface, to the isolated and riparian wetland modules of HYDROTEL, a semi-distributed, process-based, deterministic model, on two watersheds located in the province of Quebec, Canada. The analysis accounted for: (i) the spatial variability by assessing the sensitivity at various locations in the watersheds and by compiling sensitivity indices for wetland networks discretized following the Strahler order classification which quantifies the structure of hydrographic networks and (ii) the temporal variability of the sensitivity using the Generalized Global Sensitivity Matrix. The results indicate that the parameters defining the geometry of wetlands (area, depth) are the most sensitive for both isolated and riparian wetlands, and for all Strahler orders. The temporal assessment of sensitivity highlights the seasonal controlling processes, including a peaking sensitivity of the maximum water depth in wetlands during spring snowmelt, whereas the sensitivity of the evapotranspiration parameter increases during summer, but is null during winter. Results also indicate that the parameters of the isolated modules are more sensitive for wetlands located on lower stream order (upstream/headwaters) while those of the riparian modules display a greater sensitivity when wetlands are located on higher Strahler orders (downstream/main channel). These findings deepen our understanding of the impact of wetland features on stream flows and provide guidelines to plan future data acquisition campaigns in wetlandscapes.

Identifying potential sites for rainwater harvesting ponds (embung) in Indonesia's semi-arid region using GIS-based MCA techniques and satellite rainfall data.

People have used rainwater harvesting (RWH) technology for generations to a considerable extent in semi-arid and arid regions. In addition to meeting domestic needs, this technology can be utilized for agricultural purposes as well as soil and water conservation measures. Modeling the identification of the appropriate pond's location therefore becomes crucial. This study employs a Geo Information System (GIS) based multi-criteria analysis (MCA) approach and satellite rainfall data, Global Satellite Mapping of Precipitation (GSMaP) to determine the suitable locations for the ponds in a semi-arid area of Indonesia, Liliba watershed, Timor. The criteria for determining the location of the reservoir refer to the FAO and Indonesia's small ponds guideline. The watershed's biophysical characteristics and the socioeconomic situation were taken into consideration when selecting the site. According our statistical analysis, the correlation coefficient results of satellite daily precipitation were weak and moderate, but the results were strong and extremely strong for longer time scales (monthly). Our analysis shows that about 13% of the entire stream system is not suitable for ponds, whereas areas that are both good suitability and excellent suitability for ponds make up 24% and 3% of the total stream system. 61% of the locations are partially suited. The results are then verified against simple field observations. Our analysis suggests that there are 13 locations suitable for pond construction. The combination of geospatial data, GIS, a multi-criteria analysis, and a field survey proved effective for the RWH site selection in a semi-arid region with limited data, especially on the first and second order streams.

Hydrological Inferences of Morphometric Parameters for Management of River Sub-basin in Semi-arid Tropics of India using Geospatial Technique

The runoff and sediment produced from a river basin due to effective precipitation depends on the characteristics of its catchment. The catchment characteristic is site-specific and varies from basin to basin. It depends upon the topographic characteristics, climatic parameters, soil properties, geology, and human-induced activities of the catchment. Knowledge of these factors is essential for sustainable management of natural resources, i.e. soil and water and site-specific conservation measures of the basin or watershed. Morphometric parameters of the basin truly reflect the combination of all characteristics, and this is one of the major indicators for the hydrological behaviour of any watershed or catchment. For the present study, Pairi River sub-basin, situated between 81°51'58.7"- 82°26'16.04" E longitude to 19°55'51.9"- 20°55'6.9" N latitude, has been considered for the morphometric analysis using geospatial technique . Results of morphometric analysis revealed that the Pairi sub-basin has seventh order drainage network with a dendritic pattern. The dendritic drainage pattern of the subbasin shows that the basin has homogeneous lithology and a lack of structural control. The drainage density and stream frequency indicates that the sub-basin has a gentle slope and good permeability of sub-surface material. So, this sub-basin is suitable for constructing artificial groundwater recharge structures to improve the groundwater resource. The length of overland flow revealed that surface runoff may reach the stream more quickly within the sub-basin. The bifurcation ratio varies different successive stream orders. The mean bifurcation ratio is low, indicating that the geologic structure does not distort the drainage pattern and produces low to moderate peak flow in the subbasin. The shape parameters such as form factor, circulatory ratioand elongation ratio indicate that the sub-basin is elongated in shape, high infiltration capacity, and flatter hydrograph with low to moderate runoff. This study can be useful for developing and managing natural resources of the Pairi sub-basin, like site-specific soil and water conservation measures such as check dam, percolation tank, water harvesting structure and development and management of groundwater, etc

Planning and Design of Sustainable Water Harvesting Structures using Geospatial System

The most precious & essential resource on the earth surface is water for survival of life. Though the annual rainfall is between 900 to 1500 mm in southern region of India. From the southwest monsoon, still most part of the southern region of India experience water scarcity. To increase the ground water storage & surface water, water harvesting is widely suggested approach which traps the surface runoff effectively. The location to locate water harvesting structures is depends upon the availability of sufficient water quantity which enhance the infiltration. The analysis of these structures in regard of planning & site suitability involves consideration of multiple terrain and weather parameters. In this context, Remote & GIS technologies are widely adopted while planning and implementation of water harvesting structures. The aim of this paper is to identify suitable sites for water harvesting structures and to propose the design for it using geo-spatial data and GIS technology. In this study various sites are opted for development of water resource planning in Southern region of India using geospatial techniques. ArcGIS software is used for the spatial analysis and the intermediate layer was formed by overlying thematic maps of land cover land use, soil, slope, stream order map, runoff potential map.