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Sherman R. Ellis

Publications and source records attributed to Sherman R. Ellis.

5 recordsLinked to original sources
USGS1987

Runoff characteristics and washoff loads from rainfall-simulation experiments on a street surface and a native pasture in the Denver metropolitan area, Colorado

Rainfall simulation studies were conducted in conjunction with the Denver Regional Urban Runoff Program to: (1) Compare runoff quantity and quality from two different intensities of rainfall on impervious plots having identical antecedent conditions, (2) document a first flush of constituent loads in runoff from l,000-square-foot street-surface plots, (3) compare runoff characteristics from a street surface subjected to simulated rainfall with those from a 69-acre urban basin of mixed land use subjected to natural rainfall, (4) perform statistical analysis of constituent loads in the runoff with several independent variables, and (5) compare the quantity and quality of runoff from 400-square-foot plots of native grasses used for pasture and subjected to simulated rainfall with that from a 405-acre basin covered with native grasses used for pasture and subjected to natural rainfall. The rainfall simulations conducted on the street surface showed that higher intensity simulated rainfall produced a higher percentage of runoff than lower intensity rainfall. A first flush of constituent loads occurred for most constituents in the runoff from most rainfall simulations on the street surface; however, a first flush did not occur in the runoff from simulated rainfall on the pasture. The event mean concentrations of constituents in the runoff from simulated storms on the street surface were generally much smaller than the event mean concentrations of constituents in the runoff from an adjacent urban basin. Analysis of the data from the rainfall simulations on a street surface indicates that intensity of rainfall and total rainfall are important variables determining constituent loads. The design of the experiment was such that intensity of rainfall and total rainfall were highly correlated, thus precluding the development of useful regression equations to predict washoff loads. The quality of runoff from the simulated rainfall on the pasture was influenced by the disturbed perimeters of the plots; however, the runoff-to-rainfall ratios for the simulated storms fell within the range of ratios measured for natural storms over the adjacent 405-acre basin.

Professional Paper↗
USGS1979

Quantity and quality of urban runoff from three localities in the Denver Metropolitan area, Colorado

Considerable variation in constituent concentrations was shown in urban runoff data for 1975-77 from three metropolitan Denver drainage basins. Constituent concentrations, greatest during initial rainfall runoff, generally peaked midday of snowmelt runoff, corresponding with maximum melting and runoff. Instantaneous loads of constituents were largely a function of discharge. Days since last street sweeping or antecedent precipitation had no apparent effect; snowmelt-runoff loads apparently increased with number of days snow had been on the ground. Urban storm runoff may significantly contribute total ammonia nitrogen, total nonfiltrable residue, total copper, total iron, total lead, and total zinc; and snowmelt runoff may significantly contribute sodium and chloride, to local receiving waters. Data from two basins were used for calibration and verification of U.S. Environmental Protection Agency's Storm Water Management Model II for rainfall-runoff modeling of flow and total nitrogen. The model assumption that land-surface loads of total nitrogen are directly proportional to number of days prior to storm during which accumulated rainfall was less than 1.0 inch was not substantiated. (Woodard-USGS)

Colorado↗
USGS1978

Hydrologic data for urban storm runoff from three localities in the Denver metropolitan area, Colorado

Urban storm-runoff data, collected from 1975 to 1977, on three catchment areas in the Denver, Colo., metropolitan area are presented. The catchment are predominantly a single-family residential catchment area in Littleton, a multifamily residential and commercial catchment area in Lakewood, and a high-density residential and commercial catchment area in Denver. Precipitation, rainfall-runoff, snowmelt-runoff, water-quality (common constituents, nutrients, biochemical oxygen demand, coliform bacteria, and solids, trace elements, and pesticides), and catchment-area data are necessary to use the U.S. Environmental Protection Agency 's Storm Water Management Model II. The urban storm-runoff data may be used by planning, water-management, and environmental-protection agencies to assess the impact of urban storm runoff on the hydrologic system. (Woodard-USGS)

Colorado↗