Environmental Engineering Commons^™

A Two Dimensional Distributed Hydrological Model For Infiltrating Watersheds With Channel Networks, Donald Lee Currey

Civil & Environmental Engineering Theses & Dissertations

A numerical model named Old Dominion Watershed Simulation Model (ODWSM) is developed for simulating the rainfall/runoff process that occurs over watersheds. ODWSM's computational modules include the capability to simulate two-dimensional overland flow, spatially varied infiltration and depression storage, interception and channel flow for irregular and looped networks.

Overland flow computation is performed by writing the two-dimensional kinematic wave equations in an implicit finite difference form. Computational speed is gained by using an upwind differencing scheme and solving the equations in the direction of flow. This solution method allows for the calculation of infiltration and depression storage to include rainfall, current …

Runoff, Erosion, And Soil Quality Characteristics Of A Former Conservation Reserve Program Site, John E. Gilley, John W. Doran, Douglas Karlen, T. C. Kaspar

Department of Agricultural and Biological Systems Engineering: Faculty Publications

No-till and moldboard plow tillage systems were established on a former Conservation Reserve Program (CRP) site in southwest Iowa. Runoff rates from simulated rainfall events were significantly greater on sites returned to crop production than from adjoining, undisturbed CRP areas. Substantial soil loss was measured from the moldboard plow treatments, but no significant differences in erosion rates were found between the undisturbed CRP and no-till management systems. No-till management maintained levels of soil quality similar to those of CRP by preserving soil structural integrity and reducing losses of soil organic matter (SOM) associated with tillage. Conservation tillage systems which maintain …

A System Dynamics Approach To Modelling The Degradation Of Biochemical Oxygen Demand In A Constructed Wetland Receiving Stormwater Runoff, Leslie A. Mudgett

Theses and Dissertations

The objective of this research was to develop a tool to aid the Air Force Environmental Manager in the identification of the design parameters of a constructed wetland system that may be optimized to provide a desired biochemical oxygen demand (BOD) removal efficiency during the treatment of Air Force stormwater runoff. The objective is achieved through the development and use of a system dynamics model which simulates the hydrological functions of a constructed wetland as well as the processes within the wetland responsible for degradation of BOD. Based on literature review, the primary mechanism responsible for the degradation of BOD …

Fate Of Heavy Metals From Highway Runoff In Stormwater Management Systems, Harvey H. Harper

Retrospective Theses and Dissertations

The movement and fate of heavy metal inputs (Cd, Zn, Mn, Cu, Al, Fe, Pb, Ni and Cr) from highway runoff were investigated in a three-year study on 1.3 hectare retention facility near the Maitland Interchange on Interstate 4, north of Orlando, Florida. Physical characteristics of the retention pond and surrounding watershed were defined and field instrumentation was installed. Stormwater samples were collected over a one-year period, representing a wide range of intensities and antecedent dry periods. Stormwater characteristics were compared with average retention pond water quality to determine removal efficiencies for heavy metals within the pond. A total of …