Engineering Services

man on building site

Seth is a licensed professional engineer in Maryland, and has a Masters degree in Civil Engineering from the University of Maryland at College Park.   His area of focus is in stormwater management design/analysis, natural channel / stream restoration design, water resources, H&H and sediment transport modeling, and watershed management and planning. To complement his academic background, Mr. Brown is also Rosgen certified (Level II).

 

 

He has also worked with the following clients:

  • Baltimore County, Maryland
  • Counties of Fairfax, Loudoun, and Stafford in Virginia
  • Federal Highway Administration
  • National Highway Institute
  • National Academy of Science
  • Environmental Protection Agency
  • Maryland State Highway Administration
  • Cities of Falls Church, Fairfax and Alexandria in Virginia
  • Multiple HOAs, including Burke Centre, Reston Association and the Lake Caroline Community.
  • Tennessee Department of Transportation
  • City of Germantown, Tennessee
  • Meridian Airport Commission, Meridian, Mississippi

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CONFERENCE PRESENTATIONS:

Virginia Lakes and Watershed Association Annual Conference, Restoration of Four Mile Run: A Status Update, Richmond, VA, March, 2010

Virginia Lakes and Watershed Association Annual Conference, Snakeden Branch Stream Restoration: Then and Now, Richmond, VA, March, 2006

North Carolina State University Stream Restoration Institute Regional Conference on Stream Restoration, From Rhetoric to Restoration: A Case Study in Jumping Hurdles, Winston-Salem, NC, June, 2004

American Society of Civil Engineers – Environmental and Water Resources Institute Annual Conference, Automated Hydraulic Analysis: Strengths and Weaknesses, Philadelphia, PA, June, 2003

 

RELEVANT PUBLICATIONS:

Developing Performance Data Collection Protocol for Stream Restoration.  Prepared for the National Cooperative Highway Research Program, Task 8, Transportation Research Board. Prepared by GKY & Associates, Inc. and ICF Consulting.  March, 2006.

 

SPECIFIC PROJECTS AND EXPERIENCE:

Watershed Planning

Reston Watershed Plan (2001/02).  Managed several tasks involved with the development of a watershed plan for Reston, Virginia.  Tasks in this project include an intensive public outreach effort, physical and biological assessments of targeted streams, hydrologic and hydraulic modeling, GIS support (in the ArcView environment), and the development of conceptual designs for potential projects to aid in the improvement of water quality.  Stream assessments utilized protocols such as the EPA Rapid Bioassessment for habitat assessment and the Bank Erosion Hazard Index (BEHI) for physical assessment.  H&H modeling will be developed in the GIS environment using HEC-GeoHMS (for hydrological modeling) and HEC-GeoRAS (for hydraulic modeling).

Lower Gunpowder Watershed Management Study (1999/2000): Played a significant role in the development of a highly-detailed water quality management study for the Lower Gunpowder Watershed.  In the field component of the study, he aided in Level III Rosgen field assessments through out the watershed.  These assessments provided crucial geomorphic information which aided in the understanding of the fluvial geomorphic patterns in the watershed and the relative stability of streams draining it.  For the office component,a commercial Geographical Information Systems package, ArcView, was utilized to map the results of field investigation.

Stream Assessment and Restoration/Stabilization Design

Stream Assessment and Restoration, City of Fairfax, Virginia (2010): Aided in stream assessment (BEHI) and prioritization of potential stream projects for several miles of impacted stream in City of Fairfax area.  Led an effort to produce a comprehensive report on the physical condition of the streams in Fairfax City and two five-year plans to stabilize and restore the most impacted stream segments.  Prioritization schemes were developed using parameters such as feasibility, location, access, impacts to utilities and costs.

Stream Assessment and Prioritization Plan, Burke Centre HOA, Burke, Virginia (2009): Led an effort to assess several miles of stream using the Bank Hazard Erosion Index protocol (BEHI) in order to develop prioritization plan for potential stream restoration and stabilization projects for Burke Centre.  Authored a report detailing the assessment efforts and results of the analysis, and presented this information to the community.

Reedy Creek Channel Improvement Monitoring, Richmond, VA (2010): Task leader responsible for mitigation compliance for a stream restoration project associated with a flood control enhancement of Reedy Creek.  Provided in-field and in-office support to engineering and environmental science staff. In this role, he has reviewed documents, such as the 30-day post-construction monitoring report and coordinated field efforts to collect additional stream cross-section data. Was involved in the review of the six-month and annual monitoring reports, which will entail benthic collection, fish sampling, vegetative surveys, stream stability assessment, photographic documentation, and habitat assessment using the EPA RBP method.

Four Mile Run Stream Corridor Restoration, Arlington County/Alexandria, VA (2010): Task manager responsible for coordinating stream restoration design services to develop a stream corridor restoration design intended to transform an urban flood control channel with reduced environmental amenities to a more natural and self-maintaining river system. Restoration efforts will focus on use of natural channel design paradigm when developing stream designs which will minimize erosive conditions as well as provide the cross-sectional and longitudinal geometry required to maintain a stable river system.

Cameron Run Ecological Restoration, Alexandria, Virginia (2007/08): Project manager for conceptual design (35%) of 4 miles of ecological restoration of Cameron Run, a severely impacted urban riverine system that drains approximately 40 sq. mi. of developed area. Efforts include Rosgen Level II assessment of entire design reach, identification of critical areas of impact on stream ecosystem, opportunities for wetland and other water quality features (e.g., vernal pools, etc.), and 10% and 35% conceptual designs of a naturally self-maintaining system using natural channel design concepts.

NCHRP Study on Stream Restoration Protocols (2006): Led an effort to conduct an email survey of all State DOT’s to collect information on stream restoration monitoring programs and existing methods on assessing performance of stream restoration projects.  The results of this survey were compiled along with information on protocols commonly used by resource and regulatory agencies in the collection performance data on stream restoration projects.  Also, an extensive literature search was performed to find information related to the use of stream restoration as a stormwater best management practice.  The results of the study provide information on current stream monitoring protocols used by States throughout the Country along with detailed case studies to highlight these protocols.  Also, technical recommendations and guidance are provided on future protocol development and the programmatic aspects of monitoring plans.

Cardinal Glen Stream Restoration Study (2004/05):  Provided key expertise in evaluating a stream restoration project that had been designed and constructed previously by another party.  This evaluation included a review of the design as well as in-field assessment of the construction work performed.  Also, proposed several key fixes to minimize further problems with this project.  This evaluation took the form of a comprehensive report.

Upper Snakeden Branch Stream Restoration (2003/04):  Project manager for a stream restoration design in Reston, Virginia.  Performed a Level II Rosgen assessment of the existing planform and cross-sectional stream geometry.  A one-dimensional hydraulic model was developed for the existing conditions using HEC-RAS to determine areas of critical in-stream velocity and shear stress.  Using this model as a guide, a proposed geometry was designed using sound geomorphic principles, and a proposed hydraulic model was developed.  Proposed the use of in-stream rock structures such as rock and cross vanes, and imbricated rock walls, as well as more “natural” solutions, such as log vanes and coir biologs.  Developed a comprehensive planting plan and schedule.

Redhouse Run Tributary “C” Stream Restoration (1999/2000):  Project engineer and designer for the restoration of Redhouse Run Tributary C.  The stream was in need of restoration and had been severely damaged due in part to the increased urbanization of the watershed as well as a trend of upstream-moving headcuts.  The restoration required an intense field component, which was necessary to fully understand the dynamics of the geomorphology for the impaired stream.  Aided in Rosgen Level III assessments for all reaches in the study.  Determined the hydrology for the watershed using GISHydro2000, a customized GIS application working within the ArcView environment.  Led design to restore the stream relying on CADD software to visualize as well as determine the proposed geometry.

Germantown/Lateral C Stream Restoration and Stabilization (1997):  Project engineer and designer for a stream restoration/stabilization.  Lateral C, a tributary of the Wolf River, had become severely eroded and entrenched due to intense urbanization within its watershed.  He developed a HEC-2 model to simulate various peak events in a tributary of the Wolf River in the Germantown, Tennessee area, which were determined by the development of a HEC-1 model for the area.  Using the output from the HEC-2 model, a stream restoration/stabilization plan was produced which included the use of a CADD package to develop plans for the construction of the river alignment and retaining walls used in project.

Pond and Lake Management / Bathymetric and Dredging Efforts

Burke Centre Pond Inventory and Management Study, Burke, VA (2006): Led the field and office efforts to investigate the condition of several streams in the Burke Centre area and develop recommendations based upon this data.  Bathymetric surveys were performed for all of Burke Centre’s ponds to verify recent engineering reports on the condition of the ponds.  These surveys were compared with historic bathymetric mapping and original design documents to estimate sediment delivery rates.  A prioritization plan was developed using this data providing recommendations of pond improvements based upon available budget funds.  Innovative techniques, such as bio-dredging, were investigated for use in the plan.

Lake Caroline Bathymetric Survey and Assessment, Lake Caroline HOA, Caroline County, VA (2005): Led an effort to collect bathymetric data on a 277-acre man-made lake in order to aid in the determination of sedimentation rates of the impoundment facility.  Several weeks of field work was performed using HYPACK, the state of the art software for bathymetric surveying.  This data was compiled and analyzed in order to develop a bathymetric map of the entire lake bottom.  This data was compared with historic mapping to determine areas of sedimentation and estimated rates of sediment build-up.  This information, along with recommendations for future actions, was presented to the community.

Aquia Harbour Dredging Plan, Aquia Harbour HOA, Stafford County, VA (2004): Assisted in the development of a dredging plan used to obtain requisite permits for dredging activities.  Assisted in the collection of bathymetric data over a two-mile tidal riverine system and led the mapping efforts to support permitting efforts.

Design and Review (Drainage, Stormwater, Coastal)

Fairfax County Stormwater Management Retrofit Design, Fairfax, VA (2010): Responsible for conceptual as well final design and specifications for stormwater management facility retrofit in order to adhere to current code for water quality treatment.  Tasks include conceptual planning and design, involvement in public meetings, developing final plans, specifications and estimates to describe proposed work and erosion and sediment control plan, details and specifications.

City of Alexandria Basic Order Agreement, Alexandria, Virginia (2010): Task leader for the Windmill Hill Shoreline Stabilization project, overseeing the scour analysis and stabilization of a segment of tidally-influence Potomac shoreline.  The analysis requires an in-depth wave-fetch analysis to determine wave-action impacts on local conditions as well as storm surge heights.  The deliverable will include a detailed scour report along with design support for a section of vertical piling, a section of sloped rock revetment, and a natural shoreline area.

City of Alexandria Basic Order Agreement, Alexandria, Virginia (2010): Task leader for George Mason Elementary School Drainage Improvements, responsible for analysis of a hydraulically-undersized closed-drainage system in order to develop several alternatives for proposed improvements to the drainage system.  Water quality mitigation efforts will be required in order to remain in compliance with Chesapeake Bay standards, and the alternatives will have to conform with planned changes to school layout and nearby park improvements.

VDOT Location and Design Engineering Services Contract for Region IV-Northern VA (2010): Task manager responsible for hydrologic/hydraulic modeling/design and stormwater and drainage design services. He has overseen the application of standard H&H software to develop design solutions, such as water crossing improvements to reduce frequent flooding situations, and the development of cost-effective storm drainage design alternatives. Mr. Brown has overseen scour analysis required by VDOT for projects involving major stream crossings.

Route 234 / University Blvd Intersection Improvement, VDOT (2009): Acted as lead H&H design engineer responsible for storm drainage layout and stormwater management related to an interchange improvement in Prince William County, Virginia. Lane modification was required for Route 234 associated with widening to occur on University Boulevard. Oversaw the design of all inlets and pipes, as well as ensuring that VDOT water quality and quantity requirements are met.

VDOT Lucasville Road Hydraulic Crossing Improvement (2008/09): Lead engineer overseeing the hydraulic design associated with a proposed roadway improvement along Lucasville Road in PrinceWilliamCounty, Virginia. The existing pipe crossing at a local sag point in the study area is hydraulically deficient which had led to frequent roadway overtopping. Led an effort to design an improved hydraulic crossing to reduce flood potential as well as respecting roadway geometry constraints. Stormwater and storm drain design needs are associated with the project as well as stream channel improvements in the vicinity of the crossing.

Chester Stadium and Redevelopment Project in PA (2009): Task Manager responsible for providing technical support associated with water resources. Technical areas covered include erosion and sediment control, stormwater management and shoreline protection. Shoreline scour potential was analyzed by considering wave fetch, boat wake, riverine flows and ice floats. This analysis was performed to determine the relative stability of existing, and proposed, river bank slopes on site. The culmination of analyses associated with these technical areas was summarized in a water resources compendium, which was submitted to regulatory authorities.

Civil Engineering Services, Fairfax, VA (2008/09): Led several design efforts to aid the City of Fairfax’s Public Works Department as they address multiple localized flooding and pedestrian improvement projects.  Task manager for contract and acted as the primary client contact, lead and coordinate design efforts and provide public relations services when required.  Two small drainage designs as well as one pedestrian walkway improvement were included in this contract.

Georgetown Waterfront Park Wall Design, Washington, D.C. (2006): Led the design efforts for a tidally-influence portion of the Potomac River as part of the Georgetown Waterfront Park design.  The design efforts melded natural systems, a vegetated reinforced soil slope (VRSS), with harder engineered systems to enhance the aesthetic and naturalistic aspects of the interface between the park promenade and the Potomac River.

Loudoun County Stormwater Design for Loudoun County, VA (2005/06): Project manager for several stormwater design efforts to alleviate localized flooding concerns.  Designs were developed using CADD and other tools to provide conceptual-level plans for homeowner and County approval.  Project management tasks included overseeing subconsultants for various services, including surveying and geotechnical support.

Environmental Plan Review, Stafford County, VA (2005): Assisted in the review of erosion and sediment as well as stormwater management plans submitted to Stafford County.  The effort consisted of reviews of reports and other design documents related to water resources topics to ensure plans were compliant with County and State regulations.  Floodplain reviews were occasionally included in these reviews.  The reviews focused on quality control related to report calculations and assumptions as well plan documents.

Modeling (H&H, Sediment Transport, Water Quality, Floodplain)

South Wilmington Wetland Park, Wilmington, Deleware (2010): Task Manager responsible for H&H modeling and site plan development associated with the restoration and stormwater enhancement of 27 acres of historic marsh that is currently an impacted brownfield site. Developed grading and stormwater plans using complex two-dimensional hydraulic modeling (SWMM) to optimize the ecological, water quality treatment and aesthetic functions of the wetland. Acted as technical task leader by providing oversight of the integration of soil remediation information in order to minimize costs associated with disturbance of pollutant hot spot locations. Developed 10 percent design plans that integrated several hydraulic elements and connections to produce a well-functioning urban constructed/enhanced wetland.

Cameron Run Sediment Study, Alexandria, Virginia (2007/08): Led an effort to describe sediment transport properties of Cameron Run system.  The study aimed to provide technical assistance for on-going design alternative efforts by the USACE to prevent/mitigate flooding in the Huntington area along Lower Cameron Run.  This area experienced major flooding in response to a near 12-inch rain event in late June, 2006.  The final deliverable included a report that provides a proposed schedule and estimated volume of required dredge removal in order to mitigate for water surface rises due to a proposed levee to protect nearby homeowners.

Kesyer-McCool Bridge Replacement – WVDOH (2008): Oversaw efforts related to H&H analysis as well as storm drain design associated with the replacement of a 3,900 bridge on Route 220 spanning the Upper Branch of the Potomac River which connects communities in Maryland and West Virginia. Design activities for this project include H&H modeling and analysis of temporary and permanent impacts due to the proposed bridge in the Potomac River system, scour potential analysis, and bridge drainage design. HEC-RAS modeling was developed to reflect existing, temporary, and post-project hydraulic conditions. HEC-18 procedures were followed to estimate scour of three (3) large piers located within the 100-year flow limits. Rock outcroppings are common in this area, so rock core samples were provided along with particle size distribution to accurately analyze and determine predicted scour depths.

Kenmore Watershed Storm Sewer Study (2003/04):  Led the development of a model to analyze a commonly flooded area in the City of Fredericksburg to provide guidance for capitol improvements for the City.  The model utilized in this study is XPSWMM, which can simulate the impact of not only peak flow events on a system, but dynamic events as well.  XPSWMM is a commercially packaged version of the EPA-developed public-domain software package SWMM (StormWater Management Model). The objective of the project was to determine the causes of, and solutions to, flooding problems which plague a section of the City of Fredericksburg known as the Kenmore Watershed.  A major impetus for the study was severe flooding during the summer of 2000 that resulted in waist-deep water in sections of the City.  Responsible for developing a computer model of the stormwater drainage system using XP-SWMM.  The system is a complex network of inlets, culverts, storm drains, ponds, two major box flumes, a canal, and discharges to the Rappahannock River.  Modeled the existing stormwater infrastructure under various hydrologic scenarios to determine flood risk associated with different return period events.  Developed and evaluated potential solutions to the flooding problems.

Falls Church Stormwater System Modeling (2002/03):  Led an effort to model critical portions of the Falls Church stormwater system.  This effort utilized the XPSWMM modeling system, which allows for dynamic hydraulic modeling of storm sewer systems.  Field efforts were performed to locate all of the drainage structures in the system and this data was fed into a Geographic Information System (GIS) platform where it was integrated into the hydraulic model to ensure maximum accuracy of storm sewer locations and properties.  The analysis focused on located the sources and extents of localized flooding areas and proposed solutions were developed using this same software.  The results of the analysis were fed into a capitol improvement plan in order to more easily facilitate the updates for this aging and complex hydraulic system.

Storm Sewer Infrastructure Mapping (2002/0):  Acted as project manager in effort to comprehensively map the entire storm sewer system for the City of Falls Church.  In this project, survey data in a database format was converted into GIS data, which aided the City in mapping their system as well as providing a tool to quickly and accurately manage their storm sewer system.

Falls Church Flood Insurance Study for Tripps Run (2002/03):  Assisted in the development of H&H modeling for a detailed flood insurance study for the City of Falls Church, Virginia, to update Federal Emergency Management Agency (FEMA) Flood Insurance Rate Maps (FIRMs) in the area.  To accurately and efficiently model the 1.5 miles of Tripps Run in this study, GIS data was utilized whenever possible.  Helped to collect and assemble GIS data from two sources and prepare the data for analysis.  One part of this analysis was the development of hydrologic modeling, which requires an analysis of land use and zoning data to determine existing and future runoff.  HEC-GeoRAS, an automated GIS tool, was utilized to increase the efficiency and accuracy of the hydraulic model development process.

SmartGrowth Policy Analysis, Environmental Protection Administration (2003):  Led the development and implementation of an analysis to investigate the water quality impacts of varying land use patterns for multiple sites across the Country.  This effort was performed to support the SmartGrowth initiative based in the EPA’s Office of Policy.  Geographic Information Systems coverages were provided and analyzed to determine proportional land coverage for various sites using different growth patterns.  Water pollutant loadings were assigned to land usages to determine total and relative impacts and changes in water quality impacts for the varying development patterns.

Flood Study Review for FEMA FIS Program (2001):  Provided review support for flood studies submitted to the Federal Emergency Management Agency (FEMA) for their Flood Insurance Study (FIS) program.  This project consisted of technically reviewing hydraulic models, such as HEC-2 and HEC-RAS models, as well as various hydrologic models (i.e., HEC-1, HEC-HMS, SWMM, etc.) submitted by communities and private developers when their development impacts areas within the 100-year floodplain, thus affecting flood insurance rates.

Thumb Run Fecal Coliform TMDL (2000): Provided GIS support for the Thumb Run TMDL development project.  He used BASINS to perform watershed delineations to analyze land use and USGS RCH3 stream network data within the Thumb Run watershed.  This model was used to identify the prime locations for BMP implementation and to set a fecal coliform total maximum daily load, TMDL, for Thumb Run.

South Branch Patapsco River Hydrologic Study (1999):  Performed in-depth hydrologic study of the South Branch Patapsco River in the Sykesville, Maryland area.  Due to increased traffic demands, Maryland State Route 32 required widening.  This action demanded the construction of a new crossing of the South Branch of the Patapsco River.  A customized Geographical Information System (GISHYDRO) was used to obtain information on soil data as well as existing and future land use information.  A TR-20 model was developed that utilized this information to produce a series of predicted peak discharges.  Other methods of determining  peak discharge include Log-Pearson Type III analysis, USGS Regression equations, and a thorough analysis of near by USGS stream gauge information.  The results of this study were used to determine the critical discharges needed to design the proposed structure spanning the South Branch Patapsco River.

Ken Branch Culvert Analysis (1999):  Worked as part of a team that analyzed a culvert system for the Ken Branch crossing of Maryland State Route 191.  The culvert system had historically been hydraulically inadequate which has caused a hazard to automobile traffic in the area.  Through the analysis of the system using HEC-RAS software, the team suggested improvements to the system to alleviate the flooding.

Meridian Municipal Airport Drainage Retrofit (1997):  Performed a detailed hydrologic and hydraulic study of the Meridian Municipal Airport in Meridian, Mississippi to determine actions required by the airport to become FAA compliant with regards to drainage conditions.  The hydrology of the site was determined through the employment of the HEC-1 computer program.  Hydraulics for the site were assessed through the use of FAA and locally-accepted methods for culvert analysis and design.  An extensive field inspection was performed to identify drainage lines that did not meet the proper FAA requirements.  Finally, several retrofit plan alternatives were considered, with budget constraints, before the adoption of a suggested plan of action.

FHWA National Bridge Scour Program, Tennessee Department of Transportation (1997):  Project engineer in effort to model and predict bridge scour for rural bridges in Western Tennessee to comply with the National Bridge Scour Program.  Was involved in all phases of the program, which included in-field bridge inspection as well as WSPRO model development.  Used WSPRO modeling and HEC-18 to predict scour depths at bridge piers and abutments.  Using the scour predictions produced by HEC-18, a detailed structural analysis was performed to determine the relative structural bridge stability.