ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05527.x

出版商:Wiley    

年代:1985

数据来源: WILEY

摘要:

The Supreme Court of Colorado ruled that a developed water right for tributary water that was independent of the priority system could not be recognized.

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05529.x

出版商:Wiley    

年代:1985

数据来源: WILEY

摘要:

Colorado Governor Lamm's views on necessary changes in water resources planning were excerpted from an article he wrote for the March–April 1985 issue of Colorado Municipalities.

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05532.x

出版商:Wiley    

年代:1985

数据来源: WILEY

摘要:

Executive Director David B. Preston will retire as of Oct. 31, 1985. He shared his philosophy and recollections with Ida M. Sayre, associate editor of the Journal, in late March 1985.

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05533.x

出版商:Wiley    

年代:1985

数据来源: WILEY

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05534.x

出版商:Wiley    

年代:1985

数据来源: WILEY

摘要:

The analyses of data gathered in AWWA surveys in 1976, 1978, and 1980 are simple—consisting primarily of means, medians, and frequency distributions for common water utility parameters. Water use in gallons per capita per day (litres per capita per day) was on a stable plateau from 1970 to 1980, with mean and median values of about 160 and 150 gpcd (606 and 568 L/d per capita), respectively. Analysis of rural water districts as a separate class was made possible for the first time by their increased participation in the 1980 survey. Their per‐capita water use was somewhat less than that of similar municipal utilities, whereas their rates were from one third higher to double, depending on the size of the rural district. For municipal utilities, water rates essentially doubled from 1970 to 1980, but this was still not enough to keep up with inflation during that decade.

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05536.x

出版商:Wiley    

年代:1985

数据来源: WILEY

摘要:

Dissolved‐air flotation as a primary clarification stage for the production of potable water is particularly effective for the treatment of algae‐laden waters and low‐turbidity, highly colored waters. Flotation has several process advantages over sedimentation—it can produce better water quality; it can be operated at high surface loadings, resulting in relatively small and shallow plants; and it can be started up quickly, with a steady water quality being achieved within 45 min. Also, the solids concentration of the sludge produced is significantly higher (about 3 percent) than that of sludge produced by sedimentation. This article discusses the design parameters for dissolved‐air flotation plants and gives detailed information on the design of flocculation and flotation tanks, the air saturation system, the production of microbubbles, and the different sludge removal systems that can be used. Performance data are given for flotation plants used for clarification of several raw waters, with special emphasis on the treatment of algae‐laden waters and low‐turbidity, highly colored waters. A cost comparison between flotation and sedimentation is also presented, taking into account both capital and operating costs. The overall costs of the two processes are similar. Therefore, the final process selection will depend on the additional advantages offered by both processes.

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05537.x

出版商:Wiley    

年代:1985

数据来源: WILEY

摘要:

Recharge wells can be used for replenishing groundwater, for regulating the flow of contaminated or brackish groundwater, and for limiting the catchment area of a groundwater pumping station. Computer models used to study the flow of groundwater are also examined.

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05538.x

出版商:Wiley    

年代:1985

数据来源: WILEY

摘要:

Tetrachloromethane and 1,1, 1‐trichloroethane were transformed in microcosms composed of aquifer materials to trichloromethane and 1,1‐dichloroethane, respectively. Further observations of tri‐ and tetrachloroethene in microcosms demonstrated the transformation of these compounds to dichloroethene. Biotransformation products of these four solvents by freshwater sediment microbiota, in sealed static microcosms, were determined by gas chromatography during incubation at ambient temperatures in the dark for periods of up to 16 weeks. Under conditions of neutral to acid pH, reductive potential, and the absence of oxygen and light, reductive dehalogenation of these four compounds occurred. Chlorinated alkenes were consistently more resistant to biotransformation than the chlorinated alkanes.

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05539.x

出版商:Wiley    

年代:1985

数据来源: WILEY

摘要:

The removal of barium (Ba) and radium (Ra), which are found in many groundwater sources, was achieved in laboratory studies with an ion exchange process. In the studies, a strong acid resin in the calcium form effectively removed Ba2+and Ra2+to meet standards. The resin was regenerated with reclaimed brine, which would reduce disposal problems in actual practice. Total hardness, alkalinity, pH, and other water quality parameters remained unchanged. Additional research is needed, however, to refine the process and establish the costs.

ISSN:0003-150X    

DOI:10.1002/j.1551-8833.1985.tb05540.x

出版商:Wiley    

年代:1985

数据来源: WILEY