Engineering Commons^™

Faa Storm Water Program, W. H. Espey Jr., Raymond Rose, George I. Legarreta

United States Department of Transportation -- Publications & Papers

United states Environmental Protection Agency (EPA) promulgated regulations in November 16, 1991 pursuant to the Clean Water Act in the issuance of National Pollution Discharge Elimination System (NPDES) permit application regulations for storm water discharge. These regulations concern certain municipal and industrial activities. Air transportation facilities are included in the industrial activity category. The EPA storm water regulations specifically target airport deicing operations as an industrial activity. These regulations may increase Airport Improvement Program (AlP) trust fund expenditures for storm water control improvements. The Federal Aviation Administration (FAA), therefore, initiated a storm water program to assist airport operators in complying …

Magnitude Of The Scour Evaluation Program, Lawrence J. Harrison

United States Department of Transportation -- Publications & Papers

Tens of millions of dollars have been spent over the years on Federal-aid highway system bridges damaged by floods. Nearly 500,000 of the 577,000 existing bridges within the National Bridge Inventory are over waterways. The screening of these bridges over waterways for scour susceptibility will be completed, for the most part, by October 1992. The Federal Highway Administration has established January 1997 as the completion date for the scour evaluations of all existing bridges identified as scour susceptible. A cost-effective means of determining the specifics of bridges with unknown foundations is not currently available. Pending the development of technology to …

Scour Evaluations Of Existing Bridges, Michael J. Fraher

United States Department of Transportation -- Publications & Papers

The collapse of the Schoharie Creek Bridge on April 5, 1987 was a catastrophic instantaneous failure caused by scour of the bridge foundation. This particular collapse received wide media attention due to a home video of part of the collapse, the location on the New York State Thruway and the tragic loss of life. This particular collapse was not the first major interstate highway bridge failure attributed to scour of foundations. It is fair to say, however, that this was the event that finally brought stream stability and bridge scour issues to the attention of highway administrators and bridge engineers …

Merging Field & Laboratory Bridge Scour Data, J. Sterling Jones, Peggy A. Johnson, Arthur C. Parola

United States Department of Transportation -- Publications & Papers

Highway engineers are struggling with a major effort to assess and evaluate our nation's bridges for scour. Advanced technology is urgently needed to make a meaningful impact on this effort. This paper describes a need to focus laboratory and field research studies on a better understanding of the bridge scour processes.

An Evaluation Of Highway Flood Damage Statistics, Jennifer Rhodes, Roy Trent

United States Department of Transportation -- Publications & Papers

Hydraulic events result in thousands of incidents of property damage each year. The U. S. Army Corps of Engineers estimates that annual damage averages over $2 billion (CaE, 1991). Federal, state, and local agencies have set up emergency assistance programs to help pay these unusually heavy expenses. Despite the detail of the policies regulating such programs, a comprehensive database describing the causes and consequences of flood losses does not exist. In an effort to obtain clear and consistent statistics on highway related damage, the disaster files of the Federal Highway Administration's (FHWA) Emergency Relief (ER) Fund and the Federal Emergency …

"Status Of Scour Instrumentation Development", Roy Trent, Ian Friedland

United States Department of Transportation -- Publications & Papers

Improved understanding of scour and sedimentation processes near and at highway bridges is dependant on collecting reliable field data. Field data collection programs, however, have been hindered by inadequacies in instrumentation and measurement technologies. Through a coordinated program of research, the Federal Highway Administration (FHWA), State Highway Agencies (SHAs), National Cooperative Highway Research Program (NCHRP), and other agencies are working on scour instrumentation. Investigations are underway to develop a wide range of equipment types for many purposes and needs, e.g., portable equipment to be used by field crews during floods for scour inspection or measurement of scour processes; fixed equipment …

Risk-Costs For Scour At Unknown Bridge Foundations, G. Kenneth Young, Stuart M. Stein, Roy Trent

United States Department of Transportation -- Publications & Papers

A risk method sets priorities for bridge foundation information gathering. Scour failure risk is the product of failure cost and the probability of failure. The method is based on data (much of which is subjective) in the National Bridge Inventory, NBI. Risk determines the ranking of bridges for foundation data gathering in support of scour evaluation; high risks could vanish if substantial foundations are discovered.

Final Environmental Assessment For Endangered Species Habitat Enhancement/Creation Along Tile Missouri River Main Stem System

US Army Corps of Engineers

The interior least tern (Sterna antillarum) and the piping plover (Charadrius melodus) are federally endangered and threatened species, respectively, which nest on sandbars in the Missouri River. This nesting habitat has been decreasing in past years, at least in part due to vegetative encroachment. Vegetation is no longer regularly scoured from sandbars by heavy spring flows and/or ice, primarily because flows are regulated by the main stem dams. New sandbar creation is uncommon because the river carries less sediment and is no longer meandering along much of its course. Bank erosion still continues to supply sediment …

Biological Discussion Missouri National Recreational River Rehabilitation Gavins Point Dam To Ponca State Park, Nebraska & South Dakota

US Army Corps of Engineers

The corps of Engineers has received funding for the rehabilitation of the section 32 erosion control projects along the Missouri National Recreational River (MNRR). The project rehabilitation work is as outlined on the attached construction schedule.

Since the Fish & WIldlife's biological opinion on the section 32 program dated March 10, 1980, additional species that may occur in the program area have been listed, including the interior least tern, piping plover, the American burying beetle, and the pallid sturgeon.

The American burying beetle is listed as a federally endangered species in South Dakota. Extant populations are known to occur only …

Biological Assessment Missouri National Recreational River

US Army Corps of Engineers

This is in response to your May 21, 1992, letter requesting review and concurrence on a biological assessment prepared to evaluate routine actions of Section 404 and Section 10 of the Clean Water Act along the Missouri National Recreational River. This response has been prepared in coordination with the U.S. Fish and Wildlife Service's (Service) Nebraska Fish and Wildlife Enhancement Office.

This revision of your March 6, 1991, assessment addressed many of the concerns and recommendations that we brought to your attention in our April 2, 1991, letter to Mr. Kenneth Cooper and subsequent meeting on May 6, 1991. However, …

Dynamic Plug Flow Reactor Network Model For Contaminant Transport In Water Distribution Systems, James Uber, Ken Hickey, Mao Fang, Lew Rossman

United States Environmental Protection Agency: Staff Publications

We present a network water quality model that idealizes the distribution system as a network of ideal flow reactors, namely plug flow reactors. The plug flow reactors are linked together through an assumption of complete mixing at the network nodes. The resulting system of coupled 2-D (space - time) partial differential equations are discretized spatially using a finite difference scheme, and solved by numerical integration. The model will be evaluated with regard to its prediction capabilities, relative to previous modeling efforts.