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Christiane I. Mulvihill

Publications and source records attributed to Christiane I. Mulvihill.

10 recordsLinked to original sources
USGS2012

Optimizing bankfull discharge and hydraulic geometry relations for streams in New York state

This study analyzes how various data stratification schemes can be used to optimize the accuracy and utility of regional hydraulic geometry (HG) models of bankfull discharge, width, depth, and cross-sectional area for streams in New York. Topographic surveys and discharge records from 281 cross sections at 82 gaging stations with drainage areas of 0.52-396 square miles were used to create log-log regressions of region-based relations between bankfull HG metrics and drainage area. The success with which regional models distinguished unique bankfull discharge and HG patterns was assessed by comparing each regional model to those for all other regions and a pooled statewide model. Gages were also stratified (grouped) by mean annual runoff (MAR), Rosgen stream type, and water-surface slope to test if these models were better predictors of HG to drainage area relations. Bankfull discharge models for Regions 4 and 7 were outside the 95% confidence interval bands of the statewide model, and bankfull width, depth, and cross-sectional area models for Region 3 differed significantly ( p < 0.05) from those of other regions. This study found that statewide relations between drainage area and HG were strongest when data were stratified by hydrologic region, but that co-variable models could yield more accurate HG estimates in some local regional curve applications.

New York↗
USGS2009

Fish Communities and Habitat of Geomorphically Stable Reference Reaches in Streams of the Catskill Mountain Region, New York

In 2002, the U.S. Geological Survey, in cooperation with the New York City Department of Environmental Protection, began a 5-year study to develop a database that documents the physical and biological characteristics of nine stable reference reaches from seven streams in the New York City West of Hudson Water Supply Watershed in the Catskill Mountain region of New York State. Primary objectives of this study were to (1) develop a reference-reach database of morphology, aquatic biology, and fluvial processes, and (2) summarize the relations between fish communities, aquatic habitat, and stable stream morphology in streams in the Catskill Mountain region. Secondary objectives included documenting year-to-year variability in fish populations and stream habitat in geomorphically stable streams and demonstrating how reliably Habitat Suitability Index models can be used to characterize habitat conditions and predict the presence and abundance of populations of trout species. Fish and habitat databases were developed, and several important relations were identified. Fish-community indices differed considerably among sites where trout were present and where they were either absent or present in very low numbers; these differences were reflected in higher Habitat Suitability Index scores at trout-dominated sites. Several fish- community and habitat variables were found to be strongly associated with indices of stability and, therefore, determined to be useful tools for evaluating stream condition. Lastly, preliminary results suggest Rosgen stream type data can help refine fish and habitat relations and assist in our ability to predict habitat potential and fish-community composition.

Scientific Investigations Report↗
USGS2009

Bankfull discharge and channel characteristics of streams in New York State

Equations that relate drainage area to bankfull discharge and channel characteristics (such as width, depth, and cross-sectional area) at gaged sites are needed to help define bankfull discharge and channel characteristics at ungaged sites and can be used in stream-restoration and protection projects, stream-channel classification, and channel assessments. These equations are intended to serve as a guide for streams in areas of similar hydrologic, climatic, and physiographic conditions. New York State contains eight hydrologic regions that were previously delineated on the basis of high-flow (flood) characteristics. This report seeks to increase understanding of the factors affecting bankfull discharge and channel characteristics to drainage-area size relations in New York State by providing an in-depth analysis of seven previously published regional bankfull-discharge and channel-characteristics curves. Stream-survey data and discharge records from 281 cross sections at 82 streamflow-gaging stations were used in regression analyses to relate drainage area to bankfull discharge and bankfull-channel width, depth, and cross-sectional area. The R 2 and standard errors of estimate of each regional equation were compared to the R 2 and standard errors of estimate for the statewide (pooled) model to determine if regionalizing data reduced model variability. It was found that regional models typically yield less variable results than those obtained using pooled statewide equations, which indicates statistically significant regional differences in bankfull-discharge and channel-characteristics relations. Statistical analysis of bankfull-discharge relations found that curves for regions 4 and 7 fell outside the 95-percent confidence interval bands of the statewide model and had intercepts that were significantly diferent (p≤0.10) from the other five hydrologic regions.Analysis of channel-characteristics relations found that the bankfull width, depth, and cross-sectional area curves for region 3 were significantly different p(≤0.05) from the other six regions. It was hypothesized that some regional variability could be reduced by creating models for streams with similar physiographic and climatic characteristics. Available data on streamflow patterns and previous regional-curve research suggested that mean annual runoff, Rosgen stream type, and water-surface slope were the variables most likely to influence regional bankfull discharge and channel characteristics to drainage-area size relations. Results showed that although all of these factors had an influence on regional relations, most stratified models have lower 2 values and higher standard errors of estimate than the regional models. The New York statewide (pooled) bankfull-discharge equation and equations for regions 4 and 7 were compared with equations for four other regions in the Northeast to evaluate region-to-region differences, and assess the ability of individual curves to produce results more accurate than those that would be obtained from one model of the northeastern United States. Results indicated that model slopes lack significant diferences, though intercepts are significantly different. Comparison of bankfull-discharge estimates using different models shows that results could vary by as much as 100 percent depending on which model was used and indicated that regionalization improved model accuracy.

New York↗
USGS2007

Regionalized equations for bankfull discharge and channel characteristics of streams in New York State — Hydrologic Regions 1 and 2 in the Adirondack Region of northern New York

Equations that relate drainage area to bankfull discharge and channel characteristics (width, depth, and cross-sectional area) at gaged sites are needed to define bankfull-discharge and channel characteristics at ungaged sites and to provide information for watershed assessments, stream-channel classification, and design of stream-restoration projects. Such equations are most accurate if derived from streams within an area of uniform hydrologic, climatic, and physiographic conditions and applied only within that region. Stream-survey and discharge data from 15 active (currently gaged in 2005) streamflow-gaging stations and 1 inactive (discontinued) streamflow-gaging station in hydrologic Regions 1 and 2 were used in linear-regression analyses to relate drainage area to bankfull discharge and bankfull-channel width, depth, and cross-sectional area. The four resulting equations are the following: (1) bankfull discharge, in cubic feet per second = 49.6*(drainage area, in square miles) 0.849 ; (2) bankfull channel width, in feet = 21.5*(drainage, in square miles) 0.362 ; (3) bankfull channel depth, in feet = 1.06*(drainage area, in square miles) 0.329 ; and (4) bankfull channel cross-sectional area, in square feet = 22.3*(drainage area, in square miles) 0.694 . The coefficients of determination (R 2 ) for these four equations are 0.95, 0.89, 0.89, and 0.97, respectively. The high coefficients of determination for these equations indicate that much variability is explained by drainage area. Recurrence intervals for the estimated bankfull discharge of each stream ranged from 1.01 to 3.80 years; the mean recurrence interval was 2.13 years. The 16 surveyed streams were classified by Rosgen stream type; most were B- and C-type, with a few E- and F-type cross sections. The hydrologic Regions 1 and 2 equation for the relation between bankfull discharge and drainage area was graphically compared to curves developed for 5 other hydrologic regions in New York State. The 95-percent confidence interval for the hydrologic Regions 1 and 2 curve fully encompassed the curves for Regions 4a, 5, and 6, showing that there are very few differences in the relation between drainage area and bankfull discharge in these four regions. However, the curves for Regions 4 and 7 lay outside the 95 percent confidence intervals of the Region 3 curve, indicating that these 3 regions do not have similar bankfull-discharge to drainage area relations.

New York↗
USGS2007

Regionalized equations for bankfull-discharge and channel characteristics of streams in New York State — Hydrologic Region 3 east of the Hudson River

Equations that relate drainage area to bankfull discharge and channel characteristics (such as width, depth, and cross-sectional area) at gaged sites are needed to define bankfull discharge and channel characteristics at ungaged sites and can be used for stream-restoration and protection projects, stream-channel classification, and channel assessments. These equations are intended to serve as a guide for streams in areas of similar hydrologic, climatic, and physiographic conditions. New York State contains eight hydrologic regions that were previously delineated on the basis of high-flow (flood) characteristics. This report presents predictive equations for bankfull characteristics (discharge and channel characteristics) for streams east of the Hudson River, referred to as Hydrologic Region 3. Stream-survey data and discharge records from 12 streamflow-gaging stations were used in regression analyses to relate drainage area to bankfull discharge and bankfull channel width, depth, and cross-sectional area. The four predictive equations are: (1) bankfull discharge, in cubic feet per second = 83.8*(drainage area, in square miles) 0.679 ; (2) bankfull channel width, in feet = 24.0*(drainage area, in square miles) 0.292 ; (3) bankfull channel depth, in feet = 1.66*(drainage area, in square miles) 0.210 ; and (4) bankfull channel cross-sectional area, in square feet = 39.8*(drainage area, in square miles) 0.503 . The coefficients of determination ( R 2 ) for these four equations are 0.93, 0.85, 0.77, and 0.92, respectively. The high coefficients of determination for bankfull discharge and cross-sectional area indicate that much of the range in the variables is explained by the size of the drainage area; the smaller correlation coefficients for bankfull channel width and depth indicate that other factors also affect these relations. Recurrence intervals for the estimated bankfull discharge of each stream ranged from 1.16 to 3.35 years; the mean recurrence interval was 2.08 years. The 12 surveyed streams were classified by Rosgen stream type; most were B and C type, with occasional E- and F-type cross sections. The Region 3 equation (curve) for bankfull discharge was compared with those previously obtained for seven other hydrologic regions in New York State. The differences confirm that the hydraulic geometry of streams is affected by local climatic and physiographic conditions.

New York↗
USGS2006

Regionalized equations for bankfull-discharge and channel characteristics of streams in New York State—Hydrologic Region 7 in western New York

Computation of bankfull discharge and channel dimensions (width, depth, and cross-sectional area) at ungaged sites requires equations that relate bankfull discharge and channel dimensions to drainage-area at gaged sites. Bankfull-channel information commonly is needed for watershed assessments, stream channel classification, and the design of stream-restoration projects. Such equations are most accurate if they are derived on the basis of data from streams within a region of uniform hydrologic, climatic, and physiographic conditions and applied only within that region. New York State contains eight hydrologic regions that were previously delineated on the basis of high-flow (flood) characteristics. This report presents drainage areas and associated bankfull characteristics (discharge and channel dimensions) for surveyed streams in western New York (Region 7). Stream-survey data and discharge records from seven active and three inactive USGS streamflow-gaging stations were used in regression analyses to relate drainage area to bankfull discharge and to bankfull channel width, depth, and cross-sectional area. The resulting equations are: (1) bankfull discharge, in cubic feet per second = 37.1*(drainage area, in square miles) 0.765 ; (2) bankfull channel width, in feet = 10.8*(drainage area, in square miles) 0.458 ; (3) bankfull channel depth, in feet = 1.47*(drainage area, in square miles) 0.199 ; and (4) bankfull channel cross-sectional area, in square feet = 15.9*(drainage area, in square mile) 0.656 . The coefficients of determination (R 2 ) for these four equations were 0.94, 0.89, 0.52, and 0.96, respectively. The high coefficients of determination for three of these equations (discharge, width, and cross-sectional area) indicate that much of the range in the variables was explained by the drainage area. The low coefficient of determination for the equation relating bankfull depth to drainage area, however, suggests that other factors also affected water depth. Recurrence intervals for the estimated bankfull discharge of each stream ranged from 1.05 to 3.60 years; the mean recurrence interval was 2.13 years. The 10 surveyed streams were classified by Rosgen stream type; most were C- and E-type, with occasional B- and F-type cross sections. The equation (curve) for bankfull discharge for Region 7 was compared with those previously developed for four other hydrologic regions in New York State. The differences confirm that the hydraulic geometry of streams is affected by local climatic and physiographic conditions.

Scientific Investigations Report↗
USGS2005

Regionalized equations for bankfull-discharge and channel characteristics of streams in New York State—Hydrologic Region 5 in central New York

Equations that relate drainage area to bankfull discharge and channel dimensions (width, depth, and cross-sectional area) at gaged sites are needed to define bankfull discharge and channel dimensions at ungaged sites and to provide information for the design of stream-restoration projects. Such equations are most accurate if derived from streams within an area of uniform hydrologic, climatic, and physiographic conditions and applied only within that region. A study to develop equations to predict bankfull data for ungaged streams in New York established eight regions that coincided with previously defined hydrologic regions. This report presents drainage areas and bankfull characteristics (discharge and channel dimensions) for streams in central New York (Region 5) selected for this pilot study. Stream-survey data and discharge records from seven active (currently gaged) sites and nine inactive (discontinued gaged) sites were used in regression analyses to relate size of drainage area to bankfull discharge and bankfull channel width, depth, and cross-sectional area. The resulting equations are: (1) bankfull discharge, in cubic feet per second = 45.3*(drainage area, in square miles) 0.856 ; (2) bankfull channel width, in feet = 13.5*(drainage area, in square miles) 0.449 ; (3) bankfull channel depth, in feet = 0.801*(drainage area, in square miles) 0.373 ; and (4) bankfull channel cross-sectional area, in square feet = 10.8*(drainage area, in square miles) 0.823 . The high correlation coefficients (R 2 ) for these four equations (0.96, 0.92, 0.91, 0.98, respectively) indicate that much of the variation in the variables is explained by the size of the drainage area. Recurrence intervals for the estimated bankfull discharge of each stream ranged from 1.11 to 3.40 years; the mean recurrence interval was 1.51 years. The 16 surveyed streams were classified by Rosgen stream type; most were mainly C-type reaches, with occasional B- and F-type reaches. The Region 5 equation was compared with equations developed for six other large areas in the Northeast. The major differences among results indicate a need to refine equations so they can be applied by water-resources managers to local planning and design efforts.

Scientific Investigations Report↗
USGS2005

Regionalized equations for bankfull-discharge and channel characteristics of streams in New York State—Hydrologic Region 6 in the Southern Tier of New York

Equations that relate bankfull discharge and channel characteristics (width, depth, and cross-sectional area) to drainage-area size at gaged sites are needed to define bankfull discharge and channel dimensions at ungaged sites and to provide information for watershed assessments, stream-channel classification, and the design of stream-restoration projects. Such equations are most accurate if derived from streams within an area of uniform hydrologic, climatic, and physiographic conditions and applied only within that region. In New York State, eight hydrologic regions were previously defined on the basis of similar high-flow (flood) characteristics. This report presents drainage areas and associated bankfull characteristics (discharge and channel dimensions) for surveyed streams in southwestern New York (Region 6). Stream-survey data and discharge records from 11 active (currently gaged) sites and 3 inactive (discontinued) sites were used in regression analyses to relate bankfull discharge and bankfull channel width, depth, and cross-sectional area to the size of the drainage area. The resulting equations are: (1) bankfull discharge, in cubic feet per second = 48.0*(drainage area, in square miles) 0.842 ; (2) bankfull channel width, in feet = 16.9*(drainage area, in square miles) 0.419 ; (3) bankfull channel depth, in feet = 1.04*(drainage area, in square miles) 0.244 ; and (4) bankfull channel cross-sectional area, in square feet = 17.6*(drainage area, in square miles) 0.662 . The coefficient of determination (R 2 ) for these four equations were 0.90, 0.79, 0.64, and 0.89, respectively. The high correlation coefficients for bankfull discharge and cross-sectional area indicate that much of the variation in these variables is explained by the size of the drainage area. The smaller correlation coefficients for bankfull channel width and depth indicate that other factors also affect these relations. Recurrence intervals for the estimated bankfull discharge of each stream ranged from 1.01 to 2.35 years; the mean recurrence interval was 1.54 years. The 14 surveyed streams were classified by Rosgen stream type; most were C-type reaches, with occasional B-type reaches. The Region 6 equation (curve) for bankfull discharge was compared with equations previously developed for four other large areas in New York State and southeastern Pennsylvania. The differences among results indicate that, although the equations need to be refined by region before being applied by water-resources managers to local planning and design efforts, similar regions have similar relations between bankfull discharge and channel characteristics.

Scientific Investigations Report↗
USGS2004

Guidelines for surveying bankfull channel geometry and developing regional hydraulic-geometry relations for streams of New York State

Many disturbed streams within New York State are being restored in an effort to provide bank and bed stability and thereby decrease sedimentation and erosion. Efforts to identify and provide accurate indicators for stable-channel characteristics for ungaged streams have been hampered by the lack of regional equations or relations that relate drainage area to bankfull discharge and to channel depth, width, and cross-sectional area (bankfull hydraulic-geometry relations). Regional equations are needed to confirm bankfull hydraulic-geometry, assess stream stability, evaluate restoration needs, and verify restoration design for ungaged streams that lack stage-to-discharge ratings or historic peak-flow records. This report presents guidelines for surveying bankfull channel geometry at USGS stream gages and developing regional hydraulic-geometry relations (equations) for wadeable streams in New York. It summarizes methods to (1) compile and assess existing hydrologic, geometric, photographic, and topographic data, (2) conduct stream-reconnaissance inspections, (3) identify channel-bankfull characteristics, (4) conduct longitudinal and cross-section surveys, (5) measure stream discharge, (6) develop and refine bankfull hydraulic-geometry equations, and (7) analyze and assure data completeness and quality. The techniques primarily address wadeable streams with either active or discontinued surface-water and crest-stage gages. The relations can be applied to ungaged or actively gaged streams that are wadeable, and may be extended to non-wadeable streams (with some limitations) if they have drainage areas comparable to those used to develop the relations.

Open-File Report↗