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<br />frog large-scale mining operations are
<br />comparable to those from industries.
<br />Urban areas affect, and are affected
<br />by, distant human activities. Among
<br />the obvious effects are increased popu-
<br />lation densities and increased concen-
<br />trations of residential, industrial and
<br />commercial buildings and facilities,
<br />with resultant increases in areas that
<br />are impervious. Hydrological impacts
<br />then include the effects of these
<br />changes on the natural drainage, ru-
<br />noff, ground water, sediment, water
<br />quality, water demands, and on measures
<br />utilised for the disposal of wastes and
<br />surplus water and for the supply of
<br />water~ Among the hydrological problems
<br />associated with urbanisation are the
<br />continually increasing demands for
<br />water for various uses, changes in the
<br />physical environment that alter the na-
<br />tural water balance and the disposal of
<br />wastes that may contaminate strea~s and
<br />ground water. The most important to-
<br />pics for research are changes in sur-
<br />face runoff caused by urbanisation:
<br />quantity and quality of runoff; soil
<br />moisture and ground water: water de-
<br />mand forecasting: water quality ef-
<br />fects related to ground water: and ef-
<br />fects of waste water and sludge on the
<br />natural purification capacity of re-
<br />ceiving vaters and on aquatic life.
<br />
<br />~MERICAN SOCIETY OF CIVIL ENGINEERS.
<br />1975: -Urban sediment problems: a
<br />statement of scope, research, legisla-
<br />tion and education-. ASCE Task Commit-
<br />tee on urban sedimentation problems, J.
<br />Hydraul. Divn., Proc. ASCE, Vol.
<br />l0l(HY4), p329-340.
<br />
<br />Key words: sediment control:
<br />runoff: urbanisation: erosion
<br />trol.
<br />
<br />urban
<br />con-
<br />
<br />Present (1974) erosion control guide-
<br />lines and technology indicate that:
<br />there are sufficient and varied erosion
<br />control guidelines available for use as
<br />models for local governments. Past im-
<br />plementation experience can provide va-
<br />luable information to new programs and
<br />help avoid many initial problems.
<br />Evaluation of social and physical dam-
<br />ages still remains a weak point in ecO-
<br />nomic analyses of control systems;
<br />however, design criteria developed for
<br />agricultural areas should be reviewed
<br />for adequacy in each case until suffi-
<br />cient experience in urban areas is do-
<br />cumented and evaluated. Guideline
<br />handbooks are meant to provide general
<br />local information and should not be
<br />used arbitrarily as final design manu-
<br />als. Erosion control systems do not
<br />have to be 108 percent effective in re-
<br />ducing soil loss to be acceptable.
<br />Needed research for more useful erosion
<br />and sediment control should be focused
<br />in two general areas: on improving the
<br />application of rurally developed tech-
<br />nology to the urban situation and on
<br />developing methods and criteria for
<br />evaluating social and physical costs of
<br />various control systems relative to al-
<br />ternative costs of allowing specific
<br />amounts of sediment into specific water
<br />bodies.
<br />
<br />~MERICAN
<br />
<br />SOCIETY
<br />
<br />OF
<br />
<br />CIVIL
<br />
<br />ENG INEERS.
<br />
<br />"
<br />
<br />1975: -Committe~ report, ~SDects of
<br />hydrological effects of urbanisation-.
<br />J. "ydeaul. Divn., Proc. AseE,
<br />Vol.lU (HYS) , 9449-460.
<br />
<br />Key words:
<br />urbanisation:
<br />bibl1O'lraphies.
<br />
<br />ground
<br />low
<br />
<br />water
<br />flow:
<br />
<br />resources:
<br />streamflow:
<br />
<br />.
<br />
<br />Urbanisation both alters and compli-
<br />cates the natucal hydrologic cycle.
<br />However, the effects are often not con-
<br />sistent, but dep!:\d on thE' nature and
<br />magnitude of th~ urban influence~ The
<br />effects of urbanisation on four asoects
<br />of the hydrologic cycle are examined:
<br />(1) low flow, (2) total runoff, (3)
<br />infiltration; and (4) ground water re-
<br />charge. 80th supporting data and a se-
<br />lected bibliography are provided.
<br />Inherent in the alteration of the hy-
<br />drologic cycle by urbanisation is the
<br />contamination by urban wastes, and th~
<br />consequent pollution of the water re-
<br />source.
<br />
<br />.
<br />
<br />~MERIC~N SOCIETY OF CIVIL ENGINEERS.
<br />1975: .Conclusions, work group on
<br />user needs for problem solving-. In,
<br />Urban runoff, quantity and quality,
<br />ASCE, New York; pJ4-35.
<br />
<br />Key words:
<br />urbanisation:
<br />
<br />urban
<br />water pollution.
<br />
<br />runoff:
<br />
<br />~MERIC^N SOCIETY OF CIVIL ENGINEERS.
<br />1976: .Utility of urban runoff model-
<br />ing-. Proceedings of a s~cial ses-
<br />Sion,. Sprinq Annual Meeting, AGU, Wash-
<br />ington, DeC. ASCE, Urban Water Re-
<br />sources Research Program Technical ~em-
<br />orandum No.3l; l26pp. (NTIS PB-261
<br />460).
<br />
<br />.
<br />
<br />Key words: urbanisatjon~ urban
<br />runoff: computer models: water pollu-
<br />tion sources: data coll@ction;
<br />rainfall-runoff relations~ips:
<br />combined sewers: urban drainage;
<br />.odel studies: mathematical models.
<br />
<br />The proceedings of a Special Session,
<br />Spring Annual Meeting, American Geophy-
<br />sical Union, Washington, D.C., on 14
<br />April 1976 include three invited papers
<br />by a Panel on Local Government Model
<br />Use and Need, seven related invited pa-
<br />pers, two written discussions, and the
<br />full text of all Session floor discus-
<br />sion. A third of the about 60 partici-
<br />pants contributed to the floor discus-
<br />sion, which occupied two-fifthS of the
<br />total Session duration~ The thrust of
<br />the Session was an attempt to define
<br />reasons why mathematical models of
<br />urban runoff should be used more exten-
<br />sively and .ore effectively in local
<br />government projects: that is, why the
<br />use of more sophisticated models would
<br />be more cost-effective than simpler,
<br />traditional procedures. Rationales
<br />were identified for planning, design
<br />and automatic control applications.
<br />The Session provided an outstanding op-
<br />portunity for communication bet.ween
<br />users of the findings of research pro-
<br />ducts and the science-oriented re-
<br />searchers..
<br />
<br />.
<br />
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