GIS-Based Surface Runoff Modeling Using Empirical Technique For A River Basin In South India

Precipitation is the primary source of fresh water in the world. Surface runoff will happen when the amount of rainfall is greater than the soil’s infiltration capacity. In most water resource applications, runoff is the most important hydrological variable. Aside from these rainfall characteristics, there are a number of catchment-specific elements that have a direct impact on runoff amount and volume. This research focuses on estimating surface runoff over the lower Vellar basin, a river basin in the southern part of India, by integrating Soil Conservation Service-Curve Number (SCS-CN) method with GIS. This technique is one of the most common methods used by hydrologists for estimating surface runoff. Curve Number (CN) is an index established by the Natural Resource Conservation Service (NRCS) to denote the potential for stormwater runoff. The nature of the watershed is explored first by creating land use and land cover pattern followed by the preparation of slope, drainage, and location maps. The area taken for this study is the lower Vellar basin situated in the Cuddalore District of Tamil Nadu, India. The curve number is analyzed using the rainfall data of 15 years (2001-2015) and the runoff is being calculated. The watershed pattern of the study area is also explored being analyzed and executed. Preservation of the runoff water is also discussed.

Rainfall-Runoff Modeling Using NRCS-CN method and GIS approach

Rainfall-Runoff modeling is a hydrological modeling which is extremely important for water resources planning, development, and management. In this paper, Natural Resource Conservation Service-Curve Number (NRCS-CN) method along with Geographical Information System (GIS) approach was used to evaluate the runoff resulting from the rainfall of four stations, namely, Bilodra, Kathlal, Navavas and Rellawada of Sabarmati River basin. The rainfall data were taken for 10 years (2005-2014). The curve number which is the function of land use, soil and antecedent moisture condition (AMC) was generated in GIS platform. The CN value generated for AMC- I, II and III were 57.29, 75.39 and 87.77 respectively. Using NRCS-CN method, runoff depth was calculated for all the four stations. The runoff depth calculated with respect to the rainfall for Bilodra, Kathlal, Navavas and Rellawada shows a good correlation of 0.96. The computed runoff was compared with the observed runoff which depicted a good correlation of 0.73, 0.70, 0.76 and 0.65 for the four stations. This method results in speedy and precise estimation of runoff from a watershed.

Spatiotemporal Analysis of Water Resources in the Haridwar Region of Uttarakhand, India

Watershed management plays a dynamic role in water resource engineering. Estimating surface runoff is an essential process of hydrology, since understanding the fundamental relationship between rainfall and runoff is useful for sustainable water resource management. To facilitate the assessment of this process, the Natural Resource Conservation Service-Curve Number (NRCS-CN) and Geographic Information Systems (GIS) were integrated. Furthermore, land use and soil maps were incorporated to estimate the temporal variability in surface runoff potential. The present study was performed on the Haridwar city, Uttarakhand, India for the years 1995, 2010 and 2018. In a context of climate change, the spatiotemporal analysis of hydro meteorological parameters is essential for estimating water availability. The study suggested that runoff increased approximately 48% from 1995 to 2010 and decreased nearly 71% from 2010 to 2018. In turn, the weighted curve number was found to be 69.24, 70.96 and 71.24 for 1995, 2010 and 2018, respectively. Additionally, a validation process with an annual water yield model was carried out to understand spatiotemporal variations and similarities. The study recommends adopting water harvesting techniques and strategies to fulfill regional water demands, since effective and sustainable approaches like these may assist in the simultaneous mitigation of disasters such as floods and droughts.

Cultural Resources Report for the Cane Island Branch Section of the Buffalo Bayou Project Between Katy-Flewellen Road and Kingsland Boulevard in Fort Bend County, Texas

Gray & Pape, Inc., of Houston, Texas, under contract with BIO-WEST, Inc., has prepared the following report on cultural resources management activities in Fort Bend County, Texas. The project includes an archaeological survey of a total of approximately 0.93 kilometers (0.58 miles) along Buffalo Bayou between Katy-Flewellen Road and Kingsland Boulevard in Katy, Texas. The archaeological Area of Potential Effects is defined as the maintenance corridor, 30 to 60 meters (98 to 196 feet) long. The goal of this study was to assist Fort Bend County, the Texas Historical Commission, and the lead federal agency in determining whether or not intact cultural resources are present within areas for construction, and if so to provide management recommendations for these resources. All activities described herein were subject to Section 106 of the National Historic Preservation Act and issuance of an Antiquities Permit for Archeology (Permit 9319) applied for by Gray & Pape, Inc. on February 13, 2020, and issued by the Texas Historical Commission. No diagnostic or non-diagnostic artifacts were collected in the course of the current survey. As a project permitted through the Texas Historical Commission; however, Gray & Pape, Inc. submitted project records to the Center of Archaeological Studies at Texas State University. The Natural Resource Conservation Service is the lead federal agency for the project. Fieldwork was conducted between March 12 and March 16, 2020 and required approximately 40person hours to complete. Subsurface testing included a combination of systematic shovel testing and judgement sample auger probing. The site file research revealed two previously recorded archaeological sites (41FB101 and 41FB102) are located within the project area. At the beginning of the survey, an initial attempt was made to relocate previously recorded Sites 41FB101 and 41FB102 through surface inspection and limited shovel testing across the Area of Potential Effects along both sides of Buffalo Bayou. Recent disturbances from mechanical excavation along the channel slopes, the dumping of spoil across the surface of the two-track right-of-way along the bayou, and the active installation of sheet piling were photographed and mapped. Sites 41FB101 and 41FB102 could not be relocated within the Area of Potential Effects during the surface inspection, shovel testing or auger probing. No other historic or prehistoric artifacts or cultural features were identified as a result of this survey. During the initial reconnaissance, Rangia shells (n=8), including whole (closed) specimens and half shell, were observed on the surface in an area recently disturbed by heavy machinery. The shells were located east of Site 41FB101 along the two-track right-of-way and slope of the east bank of Buffalo Bayou. The majority of them were smaller than 3 centimeters (1.2 inches), with one whole specimen measuring approximately 6 centimeters (2.4 inches). Surface and subsurface inspection in the immediate area of these specimens failed to find evidence of associated cultural features or artifacts on the surface or in a buried context. A variety of modern bricks and brick fragments were also observed along the inner slopes of the east bank near the shell scatter. These same materials were later observed among the variety of riprap materials along the west bank of the bayou west of Site 41FB102 near a residential property immediately adjacent to the Area of Potential Effects. No additional cultural materials were observed on the surface with the exception of modern debris including plastics and aluminum cans. Gray & Pape, Inc. is not recommending a site designation for the Rangia shell or brick scatter observed during the survey for the foregoing reasons:1) there were no intact, buried deposits or features found; 2) there was no material that could be positively identified as artifacts; 3) the bricks observed were modern and likely deposited by landowners in attempts to prevent erosion; 4) the size, quantity, and inclusion of whole Rangia identified on the surface appear to be natural occurrences as opposed to the remains of an archaeological deposit or feature; and 5) it is impossible to determine the original location of the shell specimens at this time. Based on the results of this investigation, Sites 41FB101 and 41FB102 do not appear to extend into the existing easement belonging to the Fort Bend County Drainage District. Instead, both sites appear to be located on private property outside of the project Area of Potential Effects. As such, these sites have not been evaluated for National Register eligibility, but Gray & Pape, Inc. recommends that there will be no direct impact to these sites. It is also recommended that because the majority of project impacts will occur within sediments that have been repeatedly impacted by past channelization activities, the potential to identify intact, significant cultural resources is low. Gray & Pape, Inc. recommends the project be allowed to proceed as currently planned. As a protective measure during construction, high-visibility temporary fencing should be installed against the edge of the Area of Potential Effects in the vicinity of the two known sites. No additional cultural resources activities are recommended unless project plans change.

Estimation of surface runoff using NRCS curve number in some areas in northwest coast, Egypt

The sustainable agricultural development in the northwest coast of Egypt suffers constantly from the effects of surface runoff. Moreover, there is an urgent need by decision makers to know the effects of runoff. So the aim of this work is to integrate remote sensing and field data and the natural resource conservation service curve number model (NRCS-CN).using geographic information systems (GIS) for spatial evaluation of surface runoff .CN approach to assessment the effect of patio-temporal variations of different soil types as well as potential climate change impact on surface runoff. DEM was used to describe the effects of slope variables on water retention and surface runoff volumes. In addition the results reflects that the magnitude of surface runoff is associated with CN values using NRCS-CN model . The average of water retention ranging between 2.5 to 3.9m the results illustrated that the highest value of runoff is distinguished around the urban area and its surrounding where it ranged between 138 - 199 mm. The results show an increase in the amount of surface runoff to 199 mm when rainfall increases 200 mm / year. The north of the area may be exposed to erosion hazards more than the south and a change in the soil quality may occur in addition to the environmental imbalance in the region.

Quantitative assessment of surface runoff at arid region: a case study in the Middle of Nile Delta

Background Evaluation of surface runoff is an essential factor in the precision water and soil conservation management through their main extreme impacts on soil properties. The natural resource conservation service curve number model (NRCS-CN) model is used to estimate the magnitude of runoff. Collected topographic data is used to explain the effects of slope variation on water retention and surface runoff. Twenty-eight soil profiles are prepared in Nile delta, Egypt to cover different geomorphic units and hydrological soil groups in the study area. Results The results revealed that the highest value of surface runoff was distinguished close to the urban area and ranges between 40 and 50 mm. In urban areas, the surfaces are paved and there are no infiltration of water. Consequently, the runoff water directly flows to the storm channels. Runoff values ranging between 30 and 40 mm occurred at the north of the study area. The sloping surface and the nature of the clay soil contributed to generate more runoff than do lowland areas. Conclusion The study presented and tested the hydric runoff estimation based-model on the integrating of hydric balance parameters. The GIS tools analyze and compose these parameters to perform an indirect method for the quantity of water that results in direct surface runoff flow. This method helps to gain clear imaging of the surface runoff risks in the study area.

Incorporating Antecedent Soil Moisture into Streamflow Forecasting

This study incorporates antecedent (preceding) soil moisture into forecasting streamflow volumes within the North Platte River Basin, Colorado/Wyoming (USA). The incorporation of antecedent soil moisture accounts for infiltration and can improve streamflow predictions. Current Natural Resource Conservation Service (NRCS) forecasting methods are replicated, and a comparison is drawn between current NRCS forecasts and proposed forecasting methods using antecedent soil moisture. Current predictors used by the NRCS in regression-based streamflow forecasting include precipitation, streamflow persistence (previous season streamflow volume) and snow water equivalent (SWE) from SNOTEL (snow telemetry) sites. Proposed methods utilize antecedent soil moisture as a predictor variable in addition to the predictors noted above. A decision system was used to segregate data based on antecedent soil moisture conditions (e.g., dry, wet or normal). Principal Components Analysis and Stepwise Linear Regression were applied to generate streamflow forecasts, and numerous statistics were determined to measure forecast skill. The results show that when incorporating antecedent soil moisture, the “poor” forecasts (i.e., years in which the NRCS forecast differed greatly from the observed value) were improved, while the overall forecast skill remains unchanged. The research presented shows the need to increase the monitoring and collection of soil moisture data in mountainous western U.S. watersheds, as this parameter results in improved forecast skill.

Strong Nonagricultural Demand Keeps Agricultural Land Values Increasing

The Florida Land Value Survey, conducted by the Food and Resource Economics Department at the University of Florida, provides estimates of the value of different types of agricultural land for geographic regions of the state. The survey questionnaire was designed to obtain estimates of the market value for different types of land as of May 2005. Survey respondents included rural appraisers, farm lenders, real estate brokers, farm managers, land investors, county extension agents, personnel from the Farm Services Agency and the Natural Resource Conservation Service, county property appraisers, and other persons who develop and maintain information about rural land values in their areas. Respondents provided 185 usable county reports for the 2005 survey. This document is FE625, one of a series of the Food and Resource Economics Department, UF/IFAS Extension. Original publication date January 2006. FE625/FE625: Strong Nonagricultural Demand Keeps Agricultural Land Values Increasing (2005) (ufl.edu)

Hydro-meteorologic Assessment of October 2015 Extreme Precipitation Event on Santee Experimental Forest Watersheds, South Carolina

The extreme precipitation event on October 3-4, 2015, likely resulting from the convergence of a persistent deep easterly flow, the continuous supply of moisture, the terrain, and the circulation associated with Hurricane Joaquin off the eastern Atlantic Coast (http://cms.met.psu. edu/sref/severe/2015/04Oct2015.pdf) resulted in extreme and prolonged flooding in many parts of South Carolina. We present the precipitation amounts and intensities observed at four gauges on the USDA Forest Service Santee Experimental Forest (SEF) watersheds during this extreme event in conjunction with the antecedent conditions for 5 days prior to the event. All four rain gauges recorded 24-hr maximum rainfall of 340 mm or more during October 3-4, exceeding the Natural Resource Conservation Service (NRCS) 100-yr 24-hr design rainfall data. The 5-day antecedent measured rainfall prior to October 3 already exceeded 170 mm in three of the four gauges resulting in weekly (September 28-October 4 totals exceeding 625 mm in all gauges. Local surface water ponding of as much as 0.46 m above land surface was observed on one of the groundwater wells at an elevation of 10.395 m. The recorded stage heights at one 1st order (WS 80) and one- 2nd order (WS79) watershed gauging stations over topped the compound weir (WS 80) and weir/culvert (WS 79) outlets, with the highest stages coming near the invert of the bridge above the weir gauges and inundating large riparian areas upstream of them. Preliminary calculations yielded peak flood discharges of at least 17.4 m3 s-1 (10.9 m3 s-1 km-2 or 996 cfs/mi2) and 33.9 m3 s-1 (6.8 m3 s-1 km-2 or 620 cfs/mi2) for a 1st and 2nd order watersheds, respectively. These values exceeded the previously measured peak discharges within a 25-year record of 3.8 m3 s-1 and 11.2 m3 s-1 for these two watersheds that were recorded on October 24, 2008. When compared with computed design discharges the estimated peak flood discharges on October 4, 2015 exceed the values for a 500-yr return period. These extreme peak flood discharge results may provide insights for a need to revisit existing approaches for hydrologic analyses and design of cross drainage and other water management structures as concerns about extreme storm events resulting from global warming continue.

A Conceptual Modeling of spatio-temporal database to Estimate Runoff Changes in Urbanized Watersheds

This paper presents the development of a conceptual model of a database that allows the monitoring of changes in watersheds over time and verifies the impact of these changes on runoff. The conceptual model was developed using ER modeling techniques. ER diagrams were constructed from the semantic analysis of the variables involved in the issue of runoff in watersheds using the Curve Number method of Natural Resource Conservation Service. The conceptual model was developed based on the concepts of states and events, and the use of time as a basis for organizing spatial data allowed to record the time and place of any changes. The model of representation of spatial data based on object was employed. Through the proposed conceptual model, it is possible to store the results of several simulations for a watershed, linking each simulation to a specific event and identifying which scenario is valid at the time. Thus, it is possible to identify quantitative changes related to runoff over time and relate them to the events that caused them and the entities involved in such events. The conceptual model supports the existence of alternate realities, allowing the simulation and comparison of past and future scenarios.