Processing Modflow Research Articles

Steady-state simulation of groundwater flow in Khartoum state, Sudan

AbstractThe multi-aquifer system of the Nubian aquifer in central Sudan hydrogeological system was simulated using a three-dimensional steady-state model. The goal of the study is to detect the effect of pumping on the groundwater flow and thus, the aquifer productivity. The conceptual model of the study area was built based on the available geological and hydrogeological data guided by geophysical survey. Processing MODFLOW numerical code was used to calculate the hydraulic head and water balance under the existing boundary conditions. The model accurately simulated the hydraulic head with a determination coefficient of 0.88. The calibrated model indicated that the change in storage is 0.56 m3/day indicating the study area constitutes highly productive zone and is recommended for groundwater developments.

Influence of natural and anthropogenic factors on the hydrogeology and hydrogeochemistry of Wadi Itwad Aquifer, Saudi Arabia: Assessment using multivariate statistics and PMWIN simulation

The quantity and quality of the aquifers have been depleted by human activities such as industrialization, the use of fertilizers, excessive pumping, and the discharge of domestic wastewater. The government of Saudi Arabia (SA) built three dams in the Wadi Itwad so that Abha city could get 15,000 m3/d of water. Ten groundwater samples have been collected from ten wells (Well 1 – Well 10) located in Wadi Itwad. The samples were analyzed for total dissolved solids (TDS), electrical conductivity (EC), pH, turbidity, temperature, chloride (Cl-), potassium (K), sulphate (SO42-), nitrate (NO3–), nitrite (NO2–), fluoride (F-), ammonia (NH4), radium (Ra)-226, 228, and 234, total uranium (TU), and total faecal coliforms to evaluate the aquifer quality and quantity and to preserve it by isolating it during dry periods. Geographic Information System (GIS)–Inverse Distance Weighting (IDW) contour maps were utilized to collect and display the aquifer's hydrogeological parameters. The southeast of the downstream area shows the highest, whereas the lowest drawdown was in the northeastern and southwest parts of the downstream area. The TDS concentration was consistently within a narrow range of 573 to 606 ppm, and the anomalies in the SO42- and NO3– concentrations were consistent with and representative of runoff from agricultural areas. The low levels of NO2–, F-, and NH4 indicated negligible pollution. The concentration of radioactive elements was below the maximum contaminant level. Different hydrogeochemical processes within the aquifer system were distinguished using multivariate statistical analyses, including correlation analysis (CA), principal component analysis (PCA), hierarchical cluster analysis (HCA), and one-way analysis of variance (ANOVA). The Processing Modflow Windows (PMWIN) groundwater modeling explains that the abstraction rate needs to be lowered during the first few days of pumping and then raised again afterwards. This could aid in decreasing withdrawals and enhancing aquifer hydrogeological properties.

Impact of Boundary Conditions Dynamics on Groundwater Budget in the Campania Region (Italy)

Groundwater budgets and fluxes are affected by human activities and climate change. Numerical models are cost-effective tools to investigate the different components of the hydrologic cycle. In this study, a groundwater flow model of the unconfined aquifers of the Campania region (Italy) has been developed and calibrated in Processing Modflow 11, resulting in an accurate assessment of groundwater fluxes and their trends over fifteen years (2000–2015). The model was implemented using a high-resolution grid to capture small hydrogeological features such as wells and rivers and informed by time variable datasets used as boundary conditions (i.e., river and sea levels, aquifer recharge, evapotranspiration, and discharge from adjacent systems). Good calibration and validation performances were achieved for piezometric heads (R2 = 0.958). A set of scenarios was developed using constant boundary conditions (i.e., constant sea-level BC, uniform extinction depth BC), and the outputs were compared, quantitively assessing differences in groundwater fluxes. Simulations pointed out that using time series to inform boundary conditions in the model does not always result in a significant change in the computed fluxes. Overall, non-uniform extinction depth was the most influential condition, while both rivers and sea level conditions barely affected groundwater budgets. In addition, results highlighted the need for an accurate estimation of spatiotemporal variations of both recharge and evapotranspiration, due to their strong seasonal variability and their massive contribution to the hydrogeological cycle. Finally, a marked increase of evapotranspiration fluxes controlled by interannual variability of precipitation and atmospheric temperatures has been quantified over the modelled period.

Justification of the optimal base choice for the anti-filtration circuit during the reclamation of toxic waste storage facilities

Introduction. Storage facilities, designated for the toxic production waste and located on the premises of the former Sredne-Volzhsky chemical plant in Chapayevsk, Samara Region, are sources of negative environmental impacts. The situation is aggravated by the lack of a reliable seepage prevention circuit at toxic waste storage facilities, enclosed by natural impermeable layers. The purpose of the study is to substantiate the choice of the optimal base for seepage prevention curtains along the perimeter of toxic waste storage facilities by clarifying the filtration characteristics of impervious soils using the interpretation of special experimental filtration works, followed by the testing of the effectiveness of engineering solutions using the developed geological filtration model.
 Materials and methods. Processing Modflow is the software designed for the 3D filtration and pollutant transport modeling. The input data for a geological filtration model included technical reports on engineering surveys conducted in 2013 on the premises of the former Sredne-Volzhsky chemical plant, as well as the results of special experimental and filtration works and plant site level observations interpreted using the ANSDIMAT software.
 Results. The filtration characteristics of the clay rocks of Upper Quaternary deposits were clarified as a result of the interpretation of special experimental and filtration works by the ANSDIMAT software through graphic analytical methods, and the application of a numerical model by the Processing Modflow software to imitate these works. The resulting characteristics confirmed the usability of this engineering geological element as the base for the designed anti-seepage curtains. The Processing Modflow software was applied to confirm the high efficiency of the filtration prevention circuit, which allowed to significantly reduce inflows in toxic waste storage facilities in the course of their reclamation.
 Conclusions. In the process of reclamation of the area, occupied by the former Sredne-Volzhsky chemical plant, the option, recommended for implementation, is the installation of anti-seepage curtains around the perimeter of the toxic waste storage facilities for the circuit to be enclosed by the clay rock of the Upper Quaternary deposits. The proposed engineering solution will allow the highly toxic filtrate to be concentrated inside the toxic waste storage facilities to prevent its penetration into the environment.

Software DHI Feflow and Processing Modflow in Solving Groundwater Flow Problems for HPP Projects Design and Reconstruction in a Complex Geological and Hydrogeological Environment

Software DHI Feflow and Processing Modflow in Solving Groundwater Flow Problems for HPP Projects Design and Reconstruction in a Complex Geological and Hydrogeological Environment

Potential Use of Treated Wastewater as Groundwater Recharge Using GIS Techniques and Modeling Tools in Dhuleil-Halabat Well-Field/Jordan

Due to limited rainfall and precipitations, different developing countries depend on groundwater (G.W.) resources to challenge water scarcity. This practice of continuous and excessive G.W. pumping has led to severe water shortages and deteriorated water quality in different countries. Recharging of treated wastewater (TWW) into G.W. provides a critical solution for solving water scarcity, extending the well’s service life, and maintaining the G.W. supply. However, effective injection practice requires accurate tools and methods to determine the best location for groundwater recharge (GWRC). This work offers a new tool based on GIS–Multi-Criteria Analysis to identify the potential site and locations for GWRC with TWW. The developed methodology was applied to one of the most used well-field areas in Jordan (Dhuleil-Halabat). The G.W. flow for the B-B2/A7 formation system in the area of study was simulated using Processing Modflow (version 8.0). The analysis combined six thematic maps produced following the environmental, technical, and economic criteria to draw conclusions and recommendations. Both steady and transient conditions were used to predict the future changes that might occur under different stresses and after continuous GWR. The study evaluated three possible scenarios of artificial GWRC to evaluate the process efficiency and determine the effect on the water table level. The results revealed that only 0.05% (0.14 Km2) of the total surface area of 450 Km2 is suitable for GWRC. A GWRC with TWW at a rate of 3.65 Mm3/year (MCMY) would provide a good G.W. table recovery to 39.68 m in the year 2025, maintain a steady-state water table ≥ of 50.77 m for up to six years, and secure water supply for future generations. The proposed methodology can be used as a useful tool that can be applied to regulate the GWRC practice worldwide.

A change model of the hydraulic characteristics of the territory occupied by the landfill of solid industrial and domestic waste

Introduction. A landfill of solid industrial and domestic waste (LSIDW) is a source of negative impact on the environment. Although landfills have coverings, and they are equipped with engineering systems designated for the capturing and treatment of the biogas, LSIDW landfills still have a negative impact on subsurface and surface waters due to the spread of leachate. The purpose of this work is to obtain predictive data on changes in the hydrogeological characteristics of the territory of Salaryevo landfill, and to develop a simulation model to assess the application of technical solutions in the course of the landfill reclamation.
 Materials and methods. Processing Modflow is the software designated for the 3D modeling of filtration and transportation of pollutants. An engineering report based on the engineering and environmental surveys, performed by JSC MosvodokanalNIIproekt in the Salaryevo landfill and its environs in 2017, served as the input data designated for a simulation model.
 Results. Processing Modflow software allowed to consider three options of cutoff walls, tailored to this landfill. The installation of cutoff walls on the east and west sides of the landfill, to be performed with regard for the sorption function of the cutoff walls, is the most effective solution. The results have shown that the cutoff walls, installed to prevent the leachate from seeping, can potentially reduce the area, exposed to the impact, by 500 m.
 Conclusions. It is recommended to install a cutoff wall in the west and a sorption curtain in the east in the course of recultivating Salaryevo landfill; this solution will ensure the containment of the leachate inside the landfill and prevent its spreading.

Analysis of three-dimensional ponded drainage of a multi-layered soil underlain by an impervious barrier

A general analytical model is proposed for predicting three-dimensional seepage into ditch drains through a soil column comprising of three distinct vertical anisotropic soil layers and underlain by an impervious barrier, the drains being fed by a distributed ponding head introduced at the surface of the soil column. The problem is solved for three different situations resulting from three different locations of the water table in the ditches, namely, when the water level lies in the first layer, when it lies in the second layer and finally when it falls in the third layer. The derived solutions are validated by comparing with analytical solutions of others for a few drainage scenarios; in addition, a few numerical checks on them have also been carried out by making use of the Processing MODFLOW environment. From the study, it is seen that ponded drainage of a multi-layered soil is mostly three-dimensional in nature, particularly in locations close to the drains and that the directional conductivities of the layers play a pivotal role in deciding the hydraulics of flow associated with such a system. Further, it has also come out of the study that by suitably altering the ponding distribution at the surface of the soil, the uniformity of water movement in a multi-layered drainage system can be considerably improved mainly if the directional conductivities of the bottom layers are relatively lower than those of the top layer. As soils in nature are mostly stratified and as no analytical solution to the three-dimensional ponded ditch drainage problem currently exists for a layered soil, the proposed solutions are expected to be important additions to the already existing repertoire of drainage solutions on the subject, particularly when looked in the context of reclamation of water-logged and saline soils in layered field situations.

On the practical application of the Cooper and Jacob distance-drawdown method to analyse aquifer-pumping test data

Studies have illustrated how Infinite Acting Radial Flow (IARF) can be used as an objective criterion than the u condition to evaluate the valid of applying the Cooper and Jacob time-drawdown (1946) method. The Cooper and Jacob (1946) time-drawdown and distance-drawdown methods work on the same principle which incorporates the u condition. A similar study to assess the use of IARF as a criterion to determine the applicability of the Cooper and Jacob distance-drawdown (1946) method to analyse aquifer-pumping tests would be beneficial to groundwater practitioners. This study uses numerical groundwater flow modelling to assess and evaluate the application of the Cooper and Jacob (1946) distance-drawdown method to analyse multi-well aquifer pumping tests in ideal homogenous porous and isotropic confined aquifers under unsteady-state flow. Three multi-well aquifer-pumping tests are simulated in ideal one-layer homogeneous and isotropic confined aquifer models using Processing MODFLOW and the data is analysed by the Cooper and Jacob (1946) distance-drawdown method. The results shows that the Cooper and Jacob (1946) distance-drawdown method can only estimate correct transmissivity and storativity parameters when it is applied to observation data after IRAF. The u values calculated for the analysis vary over a wider range and do not satisfy all the literature prescribed u values. The study demonstrates and recommends how IRAF should be used as an objective criterion to determine the validity of applying the Cooper and Jacob (1946) distance-drawdown method.

Numerical groundwater flow modeling for managing the Gabes Jeffara aquifer system (Tunisia) in relation with oasis ecosystems

The Gabes Jeffara aquifer system, in southeastern Tunisia, is essentially recharged by rainfall infiltration and by groundwater inflow from the Intercalary Continental aquifer in the northwest. The increase in groundwater pumping for irrigation in recent decades has induced a serious decrease in groundwater levels, depletion of springs and degradation of oasis ecosystems. A multidisciplinary study was carried out to better understand the behavior of oasis ecosystems and aquifer systems and to provide tools and recommendations for water resources management. An important part of the study was devoted to developing a hydrodynamic flow model of the Jeffara aquifer system, which can be used as a future groundwater management tool considering different recharge or exploitation scenarios. This model was built with Processing Modflow, gathering data on geology, hydrogeology, hydrology, rainfall, piezometry, withdrawals and spring flow rates. The model was calibrated in steady state with reference to the piezometric levels measured in 1970 and in transient state for the period 1972–2014, using records from more than 200 wells and piezometers. The analysis of current and future water consumption was carried out with existing data, processed satellite images and farmer surveys. This analysis was used to define water demand scenarios combined with scenarios of decreased groundwater withdrawal, reinforced groundwater recharge and use of alternative water resources. The scenarios tested with the model show that the situation will be critical in less than 25 years without radical measures to reduce groundwater withdrawals by at least 60 MCM/year.

RESPONSES OF SHALLOW GROUNDWATER SYSTEM TO DIFFERENT WATER-SAVING PRACTICES IN TYPICAL IRRIGATION AREA IN NORTHWEST CHINA

The Jinghui Canal Irrigation District (JCID) is a highly productive agricultural area of Shaanxi province, China. Because of severe water scarcity, implementing water-saving renovation practices for agricultural sustainability is necessary. To determine the influence of different water saving practises on the shallow groundwater system in the JCID, ArcGIS and Processing MODFLOW are used to simulate changes in shallow groundwater in the irrigated farmland in this area. The results show that field water-saving measures can reduce 18.5%-33.4% of well irrigation water, and the control effect on groundwater level drawdown is prominent. The shallow groundwater level s declining rate in some areas is increased, owing to the adjustment of the agricultural planting structure. Moreover, the spatiotemporal distributions of water and soil resources do not reasonably match, which offsets the active impact of water-saving renovation in the mitigation of falling groundwater tables. The groundwater s annual average decline rate has increased from 0.535 m year-1 during 1981-1997 to 0.734 m year-1 during 2000-2014. The groundwater cone of depression shows a continuous expanding tendency. The area in which the groundwater depth is larger than 13 m has increased from 358.56 km2 in September 1997 to 612.92 km2 in September 2014. However, successful agricultural water-saving renovation requires a practical feasibility of water-saving projects, in addition to an appropriate planting structure, strong bearing capacity of farmers, water-saving propaganda, and policy implementation of agricultural subsidy and water resource management.

Groundwater potential in a drought prone Betwa river basin, Bundelkhand

This study presented a modified concept of assessing groundwater potential and water table level behavior under varying rate of recharge potential for regional scale modeling of Betwa basin using Processing ModFlow for Windows model. Betwa basin of Bundelkhand region which covered the districts of Madhya Pradesh and Utter Pradesh was selected to apply this concept. The model was calibrated and validated using observed water table elevation data for the period 2005–2013, which showed agreement between observed and predicted water table elevation. The coefficient of determination (R2) ranged between 0.74–0.87 for calibration and 0.63–0.87for validation. Scenario analysis represents the water table elevation under three varying groundwater recharge condition in Shahijina, Garrauli, Mohana and Basoda sub-basin of Betwa basin. Results shows that the scenario based on recharge with 60% of surface runoff combined with river bed recharge and natural recharge has maximum influence on groundwater recharge. Groundwater recharge under the scenario varied from 0.33–1.61 m above reference level. Recharge from 30% of surface runoff combined with river bed recharge and natural recharge varied from 0.16–1.05 m above reference level. The study shall be useful for planning of groundwater development in Betwa basin and to suggest an alternate location for development of soil and water conservation structure. The water table elevation simulation also showed that the recharge levels and the sustainability of groundwater resources cannot be ensured unless water availability in arid to semi-arid region river basin increased.

Numerical analysis of effects of an open-pit coal mine to groundwater

In this study we investigated the hydrogeological problems of an open-pit brown coal mine in the Borsod coal basin with Processing Modflow software. The coal mine is located in the valley of the Sajó-river with high transmissivity overburden layer where the traditional dewatering solutions were not encouraging due to inrush risks and low cost-efficiency. A new way of barrier forming was found out and numerically simulated to prove the efficiency of the solution. Since there are several contaminated sites in the surroundings it was a key factor to assure that the new mine dewatering technique has only a negligible effect on the groundwater regime that undisturbs the known contaminant plumes nearby.

Application of Groundwater Model to Groundwater Regulation in Cangzhou Area

The development and utilization of groundwater in Cangzhou area has led to a series of environmental and geological problems such as groundwater-level declines and land subsidence. In order to alleviate the impact of groundwater abstraction on geological environment, a calibrated, transient groundwater numerical model of the Cangzhou area was developed using Processing Modflow. Then four kinds of groundwater exploitation schemes were designed and the groundwater flow fields for different schemes in the next 50 years were simulated and predicted. By comparing and analyzing the variation of the water levels in the mining layers and the variation of groundwater storage, the optimal groundwater extraction scheme was determined.

Modification to the DRASTIC framework to assess groundwater contaminant risk in rural mountainous catchments

Mountainous headwater catchments are safeguards of quality groundwater and hence require special protection against contamination by anthropogenic sources. However, methods currently handling contamination risk fail to produce reliable results in mountainous watersheds because they overlook the influence of downhill flows and contaminant transport in the validation process. To overcome this difficulty, a new model based on so-called “concentration profiles” is presented that combines the DRASTIC framework for evaluation of intrinsic vulnerability, the categorization of land uses for evaluation of specific vulnerability to nitrate and Processing Modflow graphical user interface for simulation of nitrate transport. This model was tested in a mountainous region of Northern Portugal. The risk of groundwater contamination by nitrate was generally classified as moderate. The risky areas are regions used for agriculture and livestock production. These activities have raised nitrate concentrations of spring water (15–25 mg·L−1) downstream the risky areas. The Modflow simulations linked the risky areas (contaminant sources) to actual nitrate plumes (contaminant sinks) and modeled nitrate distributions at specific groundwater travel times. Winter plumes could be simulated for the 1-year stress period, and hence are flushable in a short time span. Spring and summer plumes could only be explained by contaminant transport during 10–20 years. In these cases, even if contaminant sources were immediately neutralized, the washout of nitrate would take decades. These results may hold back the fulfillment of sustainable development goals related to water and sanitation until 2030, and hence deserve reflection by water planners and policy makers. The modeling exercise provided extra evidence that safeguarding the catchment headwater is the keystone of groundwater quality protection in mountainous catchments. Therefore, application of this modified DRASTIC to other mountainous areas may not need to resort to Processing Modflow. The study comprises the main paper (this paper) and a MethodsX companion paper.

Optimum Groundwater Pumping Rate in Safwan-Zubair Area, Basrah Province, Using Simulated Annealing Technique

Safwan-Zubair area is located in the south –west part of Basrah Province in the south of Iraq, this area is involved within the Dibdibba plain which is considered as a part of Iraqi Western Desert. Dibdibba formation consists mainly from sand and gravel with some cementing materials like silt and clay, especially in the west of Zubair area. A linked simulation-optimization model for obtaining the optimum pumping rate of groundwater is presented in this paper. Processing Modflow for Windows (PMWIN v.5) is selected to simulate the aquifer behavior being studied. This model is integrated with an optimization model which is based on the simulated annealing (SA) technique. The calibrated values of hydraulic conductivity vary over the range (15-150) m/day; while, the calibrated values of specific yield vary over the range (0.125-0.45). The objective function converges to a maximum value of (0.636925E+8 m3/year). The percentage ratio of inactive wells is 10.9 %, many wells in the study area that occupy incorrect positions, these wells must be turn off for obtaining optimum pumping rate in the study area.

Simulation of Groundwater Flow and Migration of the Radioactive Cobalt-60 from LAMA Nuclear Facility-Iraq

This study provides a simulation of groundwater flow and advective-dispersive migration of radioactive Co-60 through an aquifer with three layers, which release or leak to groundwater from the Active Metallurgy Testing Laboratory (LAMA) Nuclear Facility-Iraq due to the nuclear accident scenario. Processing Modflow for windows (PMWIN) and Modular Three-Dimensional Multispecies Transport (MT3DMS) Models were used for this purpose. The study area and the contaminated area were 12.7 km2 and 0.005625 km2, respectively. Water levels of the groundwater have been measured in six monitoring wells. The simulation time was assumed to have started in 2016. The PMWIN model simulated the flow for two scenarios of water level in Tigris River (average and minimum water levels). The MT3DMS model simulated 10 years of plume travel, beginning in 2016. The simulated Co-60 concentrations after five years of travel were 32.34 and 34.44 μg/m3 for the two scenarios. The maximum predicted Co-60 concentrations at the end of Year 10 were 34.86 and 37.31 μg/m3, respectively. The sensitivity analysis showed that the simulated hydraulic heads in the observation wells and the simulated plume of Co-60 were highly sensitive to changes in the effective porosity but less sensitive to changes in other parameters of the dispersion and chemical reaction processes. The time necessary to reach steady state condition was predicted to be approximately 16 years. The contaminated area was isolated by using remedial process which is represented by three fully penetrating pumping wells with a suitable flow rate (0.045 m3/s) for controlling the movement of Co-60 pollutant.

An approach to validate groundwater contamination risk in rural mountainous catchments: the role of lateral groundwater flows

Computer models dedicated to the validation of groundwater contamination risk in the rural environment, namely the risk of contamination by nitrate leachates from agriculture fertilizers, are frequently based on direct comparison of risky areas (e.g., cropland, pastures used for livestock production) and spatial distributions of contaminant (nitrate) plumes. These methods are fated to fail where lateral flows dominate in the landscape (mountainous catchments) displacing the nitrate plumes downhill and from the risky spots. In these cases, there is no connection between the spatial location of risky areas and nitrate plumes, unless the two locations can be linked by a contaminant transport model. The main purpose of this paper is therefore to introduce a method whereby spatio-temporal links can be demonstrated between risky areas (contaminant sources), actual nitrate plumes (contaminant sinks) and modeled nitrate distributions at specific groundwater travel times, thereby validating the risk assessment. The method assembles a couple of well known algorithms, namely the DRASTIC model [1,2] and the Processing Modflow software (https://www.simcore.com), but their combination as risk validation method is original and proved efficient in its initial application, the companion paper of Pacheco et al. [3].

EFFECT OF CLIMATE CHANGE ON GROUNDWATER AND SALTS STORAGE IN EL SHEIKH ZUWAID-RAFAH, NORTH SINAI, EGYPT

Identifying and quantifying future climate impacts on water resources has major economic and societal implications, rendering such studies extremely important for water planners. In this research, we integrate the outputs of the general global models GDFL-ESM2M (the suitable one of the three studied models; CNRM-CM5, GFDL-ESM2M and EC-EARTH) downscaled by regional climate model (RCA4) under representative concentration pathways RCPs scenarios 8.5, into two hydrological models to provide approximations of climate change impacts on water quantity and quality in El Sheikh Zuwaid-Rafah quaternary aquifer system which is the main source of water in the area. The projected changes of the rising scenario between the periods 1980-2005 and 2050-2075 from the three studied GCMs predicted an increase in the mean of July temperature between 4.2 - 4.8 K (kelvin degree), whereas January temperature was estimated to increase between 1.8 - 5.4 K (kelvin degree). The cumulative annual precipitation was estimated to decrease by a range varied between 30% to 51%. A Simple Bias correction (SBC) technique was implemented to correct the simulated monthly precipitation series of RCA4 (GDFL-ESM2M) over Sinai Peninsula. A three dimensional finite difference flow model (Processing MODFLOW -PM5), and the implemented solute transport model (MT3D) were used to predict the groundwater and the total dissolved solids storage. Results from running the raising scenario RCP 8.5 estimated that by the hydrological year 2074 groundwater recharge would be decreased by 2.73 M.m3, leading with the yearly exploitation to decrease groundwater storage to 11.83 M.m3 and decrease in dissolve salt storage 33.1 M. Kg.

Analysis of three-dimensional transient seepage into ditch drains from a ponded field

An analytical solution in the form of infinite series is developed for predicting time-dependent three-dimensional seepage into ditch drains from a flat, homogeneous and anisotropic ponded field of finite size, the field being assumed to be surrounded on all its vertical faces by ditch drains with unequal water level heights in them. It is also assumed that the field is being underlain by a horizontal impervious barrier at a finite distance from the surface of the soil and that all the ditches are being dug all the way up to this barrier. The solution can account for a variable ponding distribution at the surface of the field. The correctness of the proposed solution for a few simplified situations is tested by comparing predictions obtained from it with the corresponding values attained from the analytical and experimental works of others. Further, a numerical check on it is also performed using the Processing MODFLOW environment. It is noticed that considerable improvement on the uniformity of the distribution of the flow lines in a three-dimensional ponded drainage space can be achieved by suitably altering the ponding distribution at the surface of the soil. As the developed three-dimensional ditch drainage model is pretty general in nature and includes most of the common variables of a ditch drainage system, it is hoped that the drainage designs based on it for reclaiming salt-affected and water-logged soils would prove to be more efficient and cost-effective as compared with designs based on solutions developed by making use of more restrictive assumptions. Also, as the developed model can handle three-dimensional flow situations, it is expected to provide reliable and realistic drainage solutions to real field situations than models being developed utilizing the two-dimensional flow assumption. This is because the existing two-dimensional solutions to the problem are actually valid not for a field of finite size but for an infinite one only.