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Key words: control; sediment ment. urban hydrology: urbanisation; control; watershed erosion erosion; manage- . In urbanisation, critial sediment prob- lems occur between the appearance of earth-moving machines on the site and the completion of the development. The first step is often to strip the natur- al vegetation from the land and level the site. Then the sub-soil is left exposed to rainfall ~nd running water. In the Detroit metropolitan area, in the summer of 196B, 2.1 percent of the ~rban zone w~s under development. This part produced nearly the same amount of eroded soil materials as the undis- turbed 97.9 percent of the area. Erosion from the developing areas aver- aged 69 tons per acre per year, com- pared with an overall r2.te for th~ me- tropolitan area of about 3.~ tons, and an overall average rate from southeast Michigan of 2.6 tons. To control ero- sion, natural vegetation should be re- tained and protected. Where in~dequate veget~tion exists, temporary or per~~n- ent vegetation should be est~blished. The exposed area should bl? limited to the s~allest practical size for th~ shortest practical ti~~. Permanent vegetation and improvements such as streets or storm sewers should be in- stalled as early as ?ossible. Sediment basins should be constructed. Diversions, grassed waterways, grade stabilisation structures, and similar measures should be installed as early as possible. BOHNERT, J.E. 1971: -The effect land use on total runoff Etudy for Salt Creek Basin, Dupage Counties, Illinois.. 5th. Illinois University: (Diss. ~bstr. 32B: p5290). of urban a case Cook. and Thesis, 152pp. Key words: techniques; urban runoff; landuse change. analytical A synthetic hydrology method. the Thornthwaite water-budget orocedure, was used to test the hypothesis that urban land use, with its impervious surfaces should increase annual runoff. Studies in Salt Creek basin, Ill., where the impervious area increased from about 7 ~ercent in 1946 to an es- timated 22 percent in 1967, showed that runoff has increased throughout this period and suggested that in suburban districts, where impervious surfaces are discontinuous, some of the surplus water generated by the impervious sur- faces may be trapped by the surrounding pervious areas; increasing urban de- velopment increases the conversion of surplus water to runoff. . . BOUWKNEGT, J. 1977: -Flood waves from im- pervious areas". In, Symposium on ef- fects of urbanisation and industriali- sation on the hydrological regime and on water quality. IAHS Publication No.123, 1'93-100. Key words: urbanisation~ storm runoff: surface runoff; mathematical models. " Precipitation falling on an impervious surface runs off, in generDl, very ra- pidly. This results in ni5charg~s to the drainage system of consid~r~bl~ in- tensity and short duration. Th~s~ es- sentially nonst~tionary flows can b~ described by the St. Venant equations. There ~re several technioues avallcbl~ to solve thes~ equations, -and in this study the author has chosen the method of char~cteristics. This method has been successfully applied to many prob- lems and two examples are given. " BOYSEN, S.M. 1974: "Predicting sediment yield in urban areas.. In, Proceedings National Symposium on urban rainfall and runoff an0 sediment control, Un- iversity of Kentucky, l~xington, Ky.; 1'199-203. Key words: urbanisation; yield; ~rosion: erosion sPdiment control. sediment control; Predicting sediment loss from urban construction sit~s is an import~nt as- p~ct in thp planning and enforcement phases of a s~~iment control nrOQrRm. The Universal Soi 1 loss Eouation (!JSLEl is an excell~nt means of-r~latina soil management, cover, and other erosion control practices to erosion in agri- cultural areas. ThE' USLE, however, cannot individually be used to estimat~ sediment yield. This pArer describes a procedure to predict sodiment yield from urban construction areas. A sedi- ment basin design procedure bdsed on trap efficiency has been used for sev- eral. years in Maryland. The USLE con- cept for relating degree of ~rosion control to sedim~nt basin trap effici- ency is as yet untried in th~ field, but it appears to be one of the best procp-dures available. The Universal Soil loss Equation is complex. Urban construction sites are not only complex but also changing daily. The complexi- ties prevent accurate estimatp.s of sed- iment yields from urbDn sites. ~RADFORD, w.L. 1977: "Urban storm water pollutant loadinqs: a statistical sum- mary through 1972". J. Water Pollu- tion Control Federation, VOl.49{4): 1'613-622. Key words: water pollution; suspended solids; data collection; water pollu- tion sources: storm runoff: urban ru- noff: mathematical models; surface runoff: bacteria. The data on urban storm water pollutant loading rates ann composition available from the literature published throuqh 1972 were used to find differences re- lated to different regions of the na- tion, gross land use typ~s, average daily traffic, type of lan~scapinq, and type of street surface. Prom 153 re- cords, the mean ann standard deviation of dust and dirt loadinq rates and com- position were calculated for each of the ind~pendent vari~bles liste~ and compared to those of the entire data setw Although apparent differences exist between subsets and the whole set of data, with some important excep- tions, the null hypothesis was accepted