摘要:

ABSTRACT:Water marketing has been proposed as one means of reallocating water supplies in the western United States. While markets for western water currently exist and may be expected to expand, the institutional constraints within which the markets must operate will limit the ultimate size and efficiency of those markets. Lack of articulation of public interests in the water resource itself leads to incomplete definition of the private rights to use the water, and it is those private rights which are sold or leased in the market. The increase in size and efficiency of any market in water rights will be dependent on the willingness of legislatures to specifically define the nature and extent of public interests in water supplies, and detailed definition is unlikely.

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03343.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:Water marketing is an increasing important topic for policy makers and water managers, especially in the Western United States. Indian reserved rights (orWintersrights) differ in significant ways from water rights under most state prior appropriation systems. AsWintersrights are quantified, a number of issues are emerging concerning the extent to which these water rights may be marketed, particularly to off‐reservation users. This paper will review the evolution of Indian reserved water rights and discuss key issues surrounding the marketing of these right

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03344.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:Voluntary water transfers through markets have been advocated by many diverse groups as a means to reallocate scarce water supplies in the semi‐arid western U.S. Although transfers of water rights have occurred almost since the creation of prior appropriation laws over a century ago, functioning water markets have been very slow to develop and are few in number. The structure, composition, administration and transactions of one of the most well established water markets, shares in the Bureau of Reclamation, Colorado‐Big Thompson project, are examined to better understand the institutional and transfer conditions that sustain an active water market. Results from a detailed study of C‐BT project records reveal that between 1970 and 1993 there were 2,698 transactions through which over one‐third of the project water changed ownership or type of use. Further analysis shows that the transactions involved many individual sellers and categories of buyers with different uses, including agricultural buyers. The transfer activity and efficiency of the C‐BT market has lead some to suggest that it be used as a model for other markets. However, because this market has fewer institutional restrictions, a well developed infrastructure and unique market conditions, it will be difficult to transfer this model to other areas without accompanying modifications in water right administration and ins

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03345.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:The concentrations of dissolved fixed inorganic nitrogen (ΣN) in Bermuda ground waters can be very high due to both natural and anthropogenic processes. The high anthropogenic flux is due to domestic cesspit operation. Mass balance calculations indicate that ground water seepage, especially rich in ΣN, is a major source of nutrients into the near shore coastal zone of Bermuda. The ground water flux of ΣN is approximately 1.5 to 4 times that of the sewage flux of ΣN to Bermuda's nearshore waters. This input of ΣN may be important in the development of algal blooms in these waters. Our work, coupled with other recent investigations, suggests that the ground water input of nutrients into nearshore marine waters is an important process glob

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03346.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:Recent stream survey data (1989–1993) from 31 stream segments of 21 streams within the upper South Umpqua Watershed Oregon were compared to 1937 stream survey data collected from these same stream segments. Current low‐flow wetted stream widths of 22 of the 31 surveyed stream segments were significantly different than in 1937; 19 stream segments were significantly wider while the remaining three stream segments were significantly narrower. In only 1 of 8 tributaries to the South Umpqua River which had headwaters within land designated wilderness area did low‐flow stream channel width increase since 1937. Conversely, 13 of the 14 tributaries to the South Umpqua River which originated from lands designated as timber emphasis were significantly wider than in 1937. The observed change in stream width was linearly related to timber harvest (r2= 0.44), road density (r2= 0.45), and the amount of large organic debris remaining within the active stream channel (r2= 0.43). These findings suggest that timber harvest and road construction may have resulted in changes in channel characteristics. These channel changes may also be a factor in the observed decline of three of the four populations of anadromous salmonids within the

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03347.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:The Rational Method continues to be the most widely used approach for estimating P‐year return frequency peak flow rates for small catchments of about one square mile or less in area. The Balanced Design Storm unit hydrograph method is perhaps the second most widely used technique for estimating peak flow rates (and is the most widely used method for developing runoff hydrographs) but is generally considered to be more accurate than the Rational Method. In this paper, both of these T‐year return frequency peak flow rate estimators are shown to be mathematically comparable. The close similarity between these two approximators may help explain why the Rational Method continues to be widely used even though other more computationally sophisticated techniques are readily available due to widespread computer softw

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03348.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:To quantify the effectiveness of best management practice (BMP) implementation on runoff, sediment, and nutrient yields from a watershed, the Nomini Creek watershed and water quality monitoring project was initiated in 1985, in Westmoreland County, Virginia. The changes in nonpoint source (NPS) loadings resulting from BMPs were evaluated by comparing selected parameters from data series obtained before, during, and after periods of BMP implementation. The results indicated that the watershed‐averaged curve number, sediment, and nutrient (N and P) concentrations were reduced by approximately 5, 20, and 40 percent, respectively, due to BMP implementation. The nutrient yield model developed by Frereet al. (1980) was applied to the water quality parameters from 175 storms, but it failed to adequately describe the observed phenomena. Seasonal changes in nutrient availability factors were not consistent with field conditions, nor were they significantly different in the pm‐ and post‐BMP periods. An extended period of monitoring, with intensive BMP implementation over a larger portion of the watershed, is required to identify BMP effectiv

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03349.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:Simulation of ground‐water flow and fate of contaminants in the subsurface environment constitutes a major phase of most environmental assessment and site remediation studies. These simulation studies yield information on spatial and temporal distributions of contaminants in the subsurface media. An important use of this information is to conduct exposure assessment studies. Spatial and temporal distributions of both chemical concentrations and exposed populations render this integrated exposure analysis task rather difficult. Geographic Information Systems (GIS), on the other hand, provide a platform in which layered, spatially distributed databases can be manipulated with ease, thereby simplifying exposure analysis tasks significantly. In this paper, we describe procedures that combine the simulation models and demographic databases under a GIS platform to automate the exposure assessment phase of a typical health assessment study. Procedures developed herein significantly simplify the post‐processing phase of the analysis, and render the overall task more ‘user friendly.’ A site‐specific application is included as a demonstration of the propose

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03350.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:Suspended solids and ammonium concentration profiles measured at five locations in Duluth‐Superior Harbor during July‐October 1985 were analyzed to quantify wind and ship effects on sediment resuspension and resulting harbor water quality. Wind components from the SE quadrant correlated strongly with depth‐averaged suspended solids concentrations that were unaffected by ship passage or thermal stratification. Winds from that quadrant have the largest fetch in the harbor. The highest correlation (r2= 0.93) was with the 6‐hour average of the ESE wind velocity component. Multiple linear regression analysis of data from post‐ship passage concentration profiles yielded numerical estimates of settling velocities of 0.08 to 0.25 cm s−1, typical of ship‐resuspended sediments, and vertical eddy diffusivities of 4 to 13 cm2s1. The results suggest that ambient vertical eddy diffusivities in the harbor are less than 4 cm2s−1in the absence of ship passages and with winds less than 5

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03351.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

ABSTRACT:Design of a stormwater pump station is a complicated procedure because of the large number of parameters that are involved. Even the most basic pump station serving a small catchment requires a computationally intensive iterative evaluation. However, the design problem consists primarily of finding the combination of temporary storage and pump capacity that accommodates runoff of the selected recurrence interval for the least cost. A procedure is developed for rapidly obtaining the needed relation between storage volume and discharge for small pump stations where a constant outflow can be assumed and the inflow hydro‐graph can be represented using the modified rational method with rainfall given by a widely‐used intensity‐duration equation. Accepting the limitations of the modified rational method and the simplifications applied to pump station operation, the procedure provides an uncomplicated way of rapidly finding the stormwater runoff volume that needs to be temporarily stored for given values of pump discharge and activation water level (or, equivalently, activation storage volume). Ultimate determination of temporary runoff storage will depend on an economic analysis of the trade‐off between storage volume and pump c

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1994.tb03352.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY