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Matthew A. Weber

Publications and source records attributed to Matthew A. Weber.

9 recordsLinked to original sources
USGS2016

Aquatic biodiversity in forests: A weak link in ecosystem services resilience

The diversity of aquatic ecosystems is being quickly reduced on many continents, warranting a closer examination of the consequences for ecological integrity and ecosystem services. Here we describe intermediate and final ecosystem services derived from aquatic biodiversity in forests. We include a summary of the factors framing the assembly of aquatic biodiversity in forests in natural systems and how they change with a variety of natural disturbances and human-derived stressors. We consider forested aquatic ecosystems as a multi-state portfolio, with diverse assemblages and life-history strategies occurring at local scales as a consequence of a mosaic of habitat conditions and past disturbances and stressors. Maintaining this multi-state portfolio of assemblages requires a broad perspective of ecosystem structure, various functions, services, and management implications relative to contemporary stressors. Because aquatic biodiversity provides multiple ecosystem services to forests, activities that compromise aquatic ecosystems and biodiversity could be an issue for maintaining forest ecosystem integrity. We illustrate these concepts with examples of aquatic biodiversity and ecosystem services in forests of northwestern North America, also known as Northeast Pacific Rim. Encouraging management planning at broad as well as local spatial scales to recognize multi-state ecosystem management goals has promise for maintaining valuable ecosystem services. Ultimately, integration of information from socio-ecological ecosystems will be needed to maintain ecosystem services derived directly and indirectly from forest aquatic biota.

California, Oregon, Washington↗
USGS1998

Level II scour analysis for brigde 5 (STOCTH00360005) on Town Highway 36, crossing Stony Brook, Stockridge, Vermont

This report provides the results of a detailed Level II analysis of scour potential at structure STOCTH00360005 on Town Highway 36 crossing Stony Brook, Stockbridge, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). Results of a Level I scour investigation also are included in appendix E of this report. A Level I investigation provides a qualitative geomorphic characterization of the study site. Information on the bridge, gleaned from Vermont Agency of Transportation (VTAOT) files, was compiled prior to conducting Level I and Level II analyses and is found in appendix D. The site is in the Green Mountain section of the New England physiographic province in central Vermont. The 23.0-mi2 drainage area is in a predominantly rural and forested basin. In the vicinity of the study site, the surface cover is forest on the left and right banks downstream and left bank upstream, while the right bank upstream is pasture with some shrubs and brush. In the study area, Stony Brook has an incised, sinuous channel with a slope of approximately 0.01 ft/ft, an average channel top width of 109 ft and an average bank height of 11 ft. The channel bed material is predominantly gravel with a median grain size (D50) of 71.7 mm (0.235 ft). The geomorphic assessment at the time of the Level I site visit on April 12, 1995, and Level II site visit on July 9, 1996, indicated that the reach was stable. The Town Highway 36 crossing of Stony Brook is a 50-ft-long, one-lane bridge consisting of one 48-foot steel-beam span (Vermont Agency of Transportation, written communication, March 23, 1995). The opening length of the structure parallel to the bridge face is 46.3 ft. The bridge is supported by a vertical, concrete abutment on the left and a vertical, concrete abutment with wingwalls on the right. The channel is skewed approximately 5 degrees to the opening while the opening-skew-to-roadway is 0 degrees. A scour hole 2.0 ft deeper than the mean thalweg depth was observed during the Level I assessment along the left side of the channel at the downstream bridge face where the flow impacts a bedrock outcrop. Scour protection measures at the site included type-1 stone fill (less than 12 inches diameter) along the right bank upstream and at the upstream and downstream ends of the left abutment, type-2 stone fill (less than 36 inches diameter) at the upstream end of the upstream right wingwall, and type-3 stone fill (less than 48 inches diameter) at the downstream end of the downstream right wingwall. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E. Scour depths and recommended rock rip-rap sizes were computed using the general guidelines described in Hydraulic Engineering Circular 18 (Richardson and Davis, 1995) for the 100- and 500-year discharges. Total scour at a highway crossing is comprised of three components: 1) long-term streambed degradation; 2) contraction scour (due to accelerated flow caused by a reduction in flow area at a bridge) and; 3) local scour (caused by accelerated flow around piers and abutments). Total scour is the sum of the three components. Equations are available to compute depths for contraction and local scour and a summary of the results of these computations follows. Contraction scour for all modelled flows ranged from 2.0 to 3.2 ft. The worst-case contraction scour occurred at the 500-year discharge. Abutment scour ranged from 9.7 to 22.2 ft. The worst-case abutment scour occurred at the 500-year discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured-streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and Davis, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

Vermont↗
USGS1997

Level II scour analysis for Bridge 7 (CHARTH00010007) on Town Highway 1, crossing Mad Brook, Charleston, Vermont

This report provides the results of a detailed Level II analysis of scour potential at structure CHARTH00010007 on town highway 1 crossing Mad Brook, Charleston, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). Results of a Level I scour investigation also are included in Appendix E of this report. A Level I investigation provides a qualitative geomorphic characterization of the study site. Information on the bridge, gleaned from Vermont Agency of Transportation (VTAOT) files, was compiled prior to conducting Level I and Level II analyses and is found in Appendix D. The site is in the White Mountain section of the New England physiographic province in north-central Vermont in the town of Charleston. The 6.59-mi 2 drainage area is in a predominantly rural and forested basin. In the vicinity of the study site, the surface cover is pasture except for the upstream left bank, which is forest. The stream banks are tree covered upstream and on the downstream left bank side. In the study area, Mad Brook has an incised, sinuous channel with a slope of approximately 0.01 ft/ft, an average channel top width of 41 ft and an average channel depth of 5 ft. The predominant channel bed materials range from gravel to boulders with a median grain size (D 50 ) of 105 mm (0.344 ft). The geomorphic assessment at the time of the Level I and Level II site visit on October 28, 1994, indicated that the reach was stable. The town highway 1 crossing of Mad Brook is a 27-ft-long, two-lane bridge consisting of one 25-foot concrete T-beam span (Vermont Agency of Transportation, written communication, August 4, 1994). The bridge is supported by vertical, concrete abutments with wingwalls. The channel is skewed approximately 10 degrees to the opening. The opening-skew-to-roadway computed from surveyed data is 5 degrees, but historical bridge records indicate this angle is closer to 10 degrees. There was scour evident during the Level I assessment due to the presence of two subfootings at the base of each abutment wall. Although the subfootings may have been constructed at the same time as the abutment walls, the subfootings may have been constructed at a later time in response to streambed degradation under the bridge. The right abutment was noted as undermined during the Level I assessment. Scour protection measures at the site were type-1 stone fill (less than 12 inches diameter) on the upstream right and downstream road embankments and type-2 stone fill on each wingwall and the downstream left bank. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E. Scour depths and rock rip-rap sizes were computed using the general guidelines described in Hydraulic Engineering Circular 18 (Richardson and others, 1995). Total scour at a highway crossing is comprised of three components: 1) long-term streambed degradation; 2) contraction scour (due to accelerated flow caused by a reduction in flow area at a bridge) and; 3) local scour (caused by accelerated flow around piers and abutments). Total scour is the sum of the three components. Equations are available to compute depths for contraction and local scour and a summary of the results of these computations follows. Contraction scour for all modelled flows ranged from 0.0 to 0.3 ft. The worst-case contraction scour occurred at the incipient overtopping discharge, which was less than the 100-year discharge. Abutment scour ranged from 6.2 to 9.4 ft. The worst-case abutment scour for the right abutment was 9.4 feet at the 100-year discharge. The worst-case abutment scour for the left abutment was 8.6 feet at the incipient overtopping discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured-streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

Vermont↗
USGS1996

Level II scour analysis for Bridge 42 (RANDVT00120042) on State Highway 12, crossing Third Branch White River, Randolph, Vermont

This report provides the results of a detailed Level II analysis of scour potential at structure RANDVT00120042 on State Highway 12 crossing the Third Branch White River, Randolph, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). A Level I study is included in Appendix E of this report. A Level I study provides a qualitative geomorphic characterization of the study site. Information on the bridge available from VTAOT files was compiled prior to conducting Level I and Level II analyses and can be found in Appendix D. The site is in the Green Mountain physiographic division of central Vermont in the town of Randolph. The 61.9-mi 2 drainage area is in a predominantly rural drainage basin. In the vicinity of the study site, the left and right banks have moderate tree cover with residential and commercial buildings on the overbank areas. In the study area, the Third Branch White River has a sinuous channel with a slope of approximately 0.013 ft/ft, an average channel top width of 133 ft and an average channel depth of 5 ft. The predominant channel bed material is gravel with a median grain size ( D 50 ) of 49.6 mm (0.163 ft). Bank material is sand and gravel (D 50 is 3.08 mm or 0.010 ft). The geomorphic assessment at the time of the Level I site visits on July 8, 1994 and December 13, 1994, indicated that the reach has experienced vertical degradation. A drop structure has been constructed downstream of the bridge to prevent further degradation. In addition to the degradation of the stream bed, there is local pier scour at the bridge site as well. At the nose of the pier in the main channel, the bed is approximately three feet below the mean thalweg and two feet below the bottom of the pier footing. The State Highway 12 crossing of the Third Branch White Riveris a 220-ft-long, two-lane bridge consisting of four concrete spans. The maximum span length is 57 ft. (Vermont Agency of Transportation, written commun., July 29, 1994). The bridge is supported by vertical, concrete abutments and three concrete piers. The toe of the left abutment is at the channel edge. The toe of the right abutment is set back on the right over-bank. The roadway centerline on the structure has a slight horizontal curve; however, the main channel is skewed approximately 5 degrees to the bridge. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E. Scour depths and rock rip-rap sizes were computed using the general guidelines described in Hydraulic Engineering Circular 18 (Richardson and others, 1993). Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. The scour analysis results are presented in tables 1 and 2 and a graph of the scour depths is presented in figure 8.

Vermont↗
USGS1996

Level II scour analysis for Bridge 16 (BRNATH00800016) on Town Highway 80, crossing Locust Creek, Barnard, Vermont

This report provides the results of a detailed Level II analysis of scour potential at structure BRNATH00800016 on town highway 80 crossing Locust Creek, Barnard, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). A Level I study is included in Appendix E of this report. A Level I study provides a qualitative geomorphic characterization of the study site. Information on the bridge, gleaned from Vermont Agency of Transportation (VTAOT) files, was compiled prior to conducting Level I and Level II analyses and can be found in Appendix D. The site is in the Green Mountain physiographic province of central Vermont in the town of Barnard. The 22.0-mi 2 drainage area is in a predominantly rural and forested basin. In the vicinity of the study site, the left banks are forested and the right banks are covered with shrub and brush. Vermont Route 12 is adjacent to the right bank. In the study area, Locust Creek has an incised channel with a slope of approximately 0.02 ft/ft, an average channel top width of 60 ft and an average channel depth of 4 ft. The predominant channel bed materials are gravel and cobble with a median grain size (D 50 ) of 102 mm (0.336 ft). The geomorphic assessment at the time of the Level I and Level II site visits on September 22, 1994 and October 12, 1994, indicated that the reach was stable. The town highway 80 crossing of Locust Creek is a 36-ft-long, one-lane bridge consisting of one 33-foot steel-beam span with timber deck (Vermont Agency of Transportation, written communication, August 23, 1994). The bridge is supported by vertical, log crib abutments with wingwalls. Type-2 stone fill (less than 36 inches diameter) protects the upstream and downstream left wingwalls and the downstream left road embankment. Type- 3 stone fill (less than 48 inches diameter) protects the upstream and downstream right wingwalls. The upstream left and downstream right road embankments are not protected and road wash is eroding these areas. The channel approach to the bridge is straight with the bridge skewed zero degrees to flow; the opening-skew-to-roadway is also zero degrees. Additional details describing conditions at the site are included in the Level II Summary, Appendix D, and Appendix E. Scour depths and rock rip-rap sizes were computed using the general guidelines described in Hydraulic Engineering Circular 18 (Richardson and others, 1993). Total scour at a highway crossing is comprised of three components: 1) long-term streambed degradation; 2) contraction scour (due to accelerated flow caused by a reduction in flow area at a bridge) and; 3) local scour (caused by accelerated flow around piers and abutments). Total scour is the sum of the three components. Equations are available to compute depths for contraction and local scour and a summary of the results of these computations follows. Contraction scour for all modelled flows ranged from 0.0 to 3.7 ft. The worst-case contraction scour occurred at the incipient-overtopping discharge, which was between the 100- and 500-year discharge. Abutment scour ranged from 17.5 to 23.2 ft. The worst-case abutment scour occurred at the 500-year discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured-streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1993, p. 48). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

Vermont↗
USGS1996

Level II scour analysis for Bridge 25 (BRNAVT00120025) on State Highway 12, crossing Locust Creek, Barnard, Vermont

This report provides the results of a detailed Level II analysis of scour potential at structure BRNAVT00120025 on State Highway 12 crossing Locust Creek, Barnard, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). A Level I study is included in Appendix E of this report. A Level I study provides a qualitative geomorphic characterization of the study site. Information on the bridge available from VTAOT files was compiled prior to conducting Level I and Level II analyses and can be found in Appendix D. The site is in the Green Mountain physiographic division of central Vermont in the town of Barnard. The 11.6-mi 2 drainage area is in a predominantly rural and forested basin. In the vicinity of the study site, the banks have woody vegetation coverage. In the study area, Locust Creek has a sinuous channel with a slope of approximately 0.023 ft/ft, an average channel top width of 49 ft and an average channel depth of 4 ft. The predominant channel bed material is cobble (D 50 is 109 mm or 0.359 ft). The geomorphic assessment at the time of the Level I and Level II site visits on September 23 and December 16, 1994, indicated that the reach was stable. The State Highway 12 crossing of Locust Creek is a 41-ft-long, two-lane bridge consisting of one 39-foot concrete slab type superstructure (Vermont Agency of Transportation, written communication, August 23, 1994). The bridge is supported by vertical, concrete abutments with wingwalls. The channel is skewed approximately 30 degrees to the opening while the opening-skew-to-roadway is 45 degrees. A scour hole 1 ft deeper than the mean thalweg depth was observed along a bedrock outcrop near the upstream left wingwall during the Level I assessment. The scour protection measures in place at the site are type-1 stone fill (less than 12 inches diameter) along the left abutment, upstream right bank, and both downstream banks; type-2 stone fill (less than 36 inches diameter) at the downstream side of the right road approach and upstream left bank; type-3 stone fill (less than 48 inches diameter) at the upstream end of the upstream right wingwall and downstream end of downstream left wingwall; type-5 (wall/ artificial levee) at the upstream end of the upstream left wingwall. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E. Scour depths and rock rip-rap sizes were computed using the general guidelines described in Hydraulic Engineering Circular 18 (Richardson and others, 1993). Total scour at a highway crossing is comprised of three components: 1) long-term streambed degradation; 2) contraction scour (due to accelerated flow caused by a reduction in flow area at a bridge) and; 3) local scour (caused by accelerated flow around piers and abutments). Total scour is the sum of the three components. Equations are available to compute depths for contraction and local scour and a summary of the results of these computations follows. Contraction scour for all modelled flows ranged from 0.0 to 1.4 ft. The worst-case contraction scour occurred at the 100-year discharge. Abutment scour ranged from 8.5 to 20.9 ft. The worst-case abutment scour occurred at the 500-year discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured-streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1993, p. 48). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

Vermont↗
USGS1996

Level II scour analysis for Bridge 25 (BRNATH00290034) on Town Highway 29, crossing Locust Creek, Barnard, Vermont

This report provides the results of a detailed Level II analysis of scour potential at structure BRNATH00290034 on Town Highway 29 crossing Locust Creek, Barnard, Vermont (figures 1-8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). Results of a Level I scour investigation also are included in Appendix E of this report. A Level I investigation provides a qualitative geomorphic characterization of the study site. Information on the bridge, gleaned from Vermont Agency of Transportation (VTAOT) files, was compiled prior to conducting Level I and Level II analyses and is found in Appendix D. The site is in the Green Mountain section of the New England physiographic province in central Vermont. The 11.5-mi 2 drainage area is in a predominantly rural and forested basin. In the vicinity of the study site, the surface cover is forest, except for pasture on the downstream right overbank. In the study area, Locust Creek has an incised, generally straight channel with a slope of approximately 0.03 ft/ft, an average channel top width of 64 ft and an average channel depth of 7 ft. The predominant channel bed materials are gravel and cobble with a median grain size (D 50 ) of 89.3 mm (0.293 ft). The geomorphic assessment at the time of the Level I and Level II site visit on October 13, 1994 and December 16, 1994, indicated that the reach was stable. The Town Highway 29 crossing of Locust Creek is a 37-ft-long, one-lane bridge consisting of one 32-foot concrete span (Vermont Agency of Transportation, written communication, August 23, 1994). The bridge is supported by vertical, concrete abutments with wingwalls. The channel is skewed approximately 25 degrees to the opening while the opening-skew-to-roadway is 25 degrees. There was no observable scour protection measure at the site. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E.

Vermont↗