Downloaded from http://egsp.lyellcollection.org/ by guest on September 27, 2021 Aspects of geology in planning F. G. Bell, J. C. Cripps, M. G. Culshaw & M. O'Hara ABSTRACT: The planning of man's environment is a complex operation which requires the interaction of many disciplines. Generally speaking, the physical development of society occurs by the implementation of a series of separate, but converging, aims which may be expressed in terms of, for instance, improvements to living conditions, public health or mobility. A development plan usually attempts to achieve these aims at minimum financial cost while reconciling many conflicting influences. So far as the use of land is concerned, since some land is inherently more suitable for some purposes than for others, there are clear cost implications in implementing a particular development plan and savings may be possible if the ground conditions are considered at an early stage. However, problems often arise with quantifying this cost due to a lack of appreciation of all the effects of a plan, including unexpected and undesirable ones. Since many natural systems pose threats to society, they should be taken into account during planning. The monetary costs may be less tangible, but security of life, disruption to production and destruction of property all reduce the well-being of society. Whether the causative hazards are the result of either planned or unplanned changes to the environment, or due to naturalprocesses, they can only be successfully predicted or avoided if their mode of interaction with human activities is understood. In this paper the opportunity is taken to explore some of themore important geological factors which may significantly influence the planned use of land. Both natural and man-made geological hazards are considered. In addition, attention is given to the sources and interpretation of geological information in the context of planning. Introduction Over recent years public concern regarding the alte- ration and degradation of the environment has caused The ultimate objective of planning is to determine a governmental and planning authorities to become more particular course of action and so involves attempting to aware of the adverse effects of indiscriminate develop- resolve perceived problems. Although the policy which ment. As a result laws have been passed to help protect the develops from planning embodies a particular course of environment from spoilation. Most policies which deal action, planning proposals are often controversial in that with land-use are concerned with either those processes they may offend one or more sections of the community. which represent threats to life, health or property includ- Hence, in the last analysis, planning policies are the ing, for instance, hazardous events, pollution of air or prerogatives of government since legislation is necessary water; or the exploitation, protection or conservation of to put them into effect. natural resources or the restoration of despoiled areas. Land-use planning represents an attempt to reduce the Since land-use inevitably involves the different de- number of conflicts and adverse environmental impacts velopment of particular areas, some type of land classifi- both in relation to society and nature. In the first instance, cation(s) constitute the basis on which land-use planning land-use planning involves the collection and evaluation is carried out. However, land should also be graded of relevant data from which plans can be formulated (Fig. according to its potential uses and capabilities. In other 1). The policies which result depend on the economic, words, indices are required to assess the environmental sociological and political influences in addition to the status of natural resources and their potential. Such perception of the problem. In this context, the primary indices should establish limits, trends and thresholds, as role of engineering geologists should be to provide well as providing insight that offers some measure of planners and engineers with sufficient information so success of national and municipal programmes dealing that, ideally, they can develop the environment in har- with environmental problems. For example, in 1976 the mony with nature. Indeed, as indicated in Fig. 2, the US Geological Survey adopted a land-use and land cover geologist can offer much useful information at all levels of classification system which has been used to compile planning and development from the initial identification maps and thereby to provide a land-use inventory of the of a social need to the construction of a dam, road, airport whole country by 1985. or town that is required to satisfy that need. Even after Obviously one of the aspects of planning which construction, further involvementmay be necessary in the intimately involves geology is the control or prevention of form of advice on hazard monitoring, maintenance, or geological processes or hazards which mitigate against remedial works. The most convenient method of provid- the interests of man. The development of planning ing the necessary geological information is usually, at policies for dealing with hazards in particular, requires an least partially, in the form of a map. assessment of the severity, extent and frequency of the From CULSHAW, M. G., BELL, F. G., CRIPPS, J. C. & O'HARA, M. (eds) 1987. Planning and Engineering Geology, Geological Society Engineering Geology Special Publication No. 4, pp. 1-38. Downloaded from http://egsp.lyellcollection.org/ by guest on September 27, 2021 2 F.G. BELL, J. C. CRIPPS, M. G. CULSHAW ~ M. O'HARA the ground conditions can affect both the viability and implementation of planning proposals. The incorpora- [ SOCIAL NEED] tion of geological information into planning processes should mean that proposals can be formulated which do IENGINEERING not conflict with the ground conditions present. GEOLOGY IPaNNE"sl IMAPSt 1 Conservation, restoration and reclamation I of land Hazards1 - 1:5o.ooo ,{NATIONAL I Land is one of the most important of human assets and since there is insufficient to satisfy the demands placed I upon it, this resource should not be wasted. What is more, + Foundation 1:5.000 '~ DISTRICT] derelict land has a blighting effect on the surrounding area Conditions , which makes its restoration highly desirable. Conservation is concerned with safeguarding natural phenomena and the preservation and improvement of the -!- geotechnical 1:500 quality of the environment. As such it is closely associated values with the geology as geology and environment are inti- mately interrelated. However, in the case of the mineral extraction industry, the geologist may find himself in conflict with the conservationist. On the other hand ~REMEDIAL l geological knowledge should be made use of in conserva- tion programmes since these should seek to make the wisest use of natural resources and in this concept there is no conflict with the geologist. I NEED FULFILLEDI Conservation is not simply preservation, it seeks to improve existing conditions rather than simply maintain- ing the status quo. Hence conservation does involve the reconciliation of differing views so that the best com- FIG. 1. The relevance of engineering geology to different stages of promise can be reached. Obviously in this context land- planning and development. (After Forster & Culshaw 1987). use is important. In some instances the same land can be used simultaneously to cater for several needs, whilst in hazard in order to evaluate the degree of risk. Once this others the uses to which it can be put are consecutive has been accomplished methods whereby the risk can be rather than concurrent and the final effect can be either to reduced have to be investigated and evaluated in terms of restore the land to its original use or to a new use which public costs and benefits. The risks associated with forms an acceptable part of the landscape. Thus a geological hazards may be reduced, for instance, by sequence of events must be planned to ensure the greatest control measures carried out against the hazard produc- efficiency in the use of resources and that the most ing agent; monitoring and warning systems which allow acceptable final state is achieved. Hence in such situa- evacuation; restrictions on development of land; and the tions, the geologist must be involved with planning from use of appropriate building codes together with structural the onset. If this is not done, then natural resources may reinforcement of property. In addition, the character of be sterilized as a consequence of premature alternative Public initiative and response l 1 t' 1 PROBLEMS COLLECT REVIEW AND AND FORMULATE AND IMPLEMENT DEFINE GOALS INTERPRET PLANS ADOPT PLANS AND DATA PLANS OBJECTIVES Evaluate impacts-environmental, social, economic, fiscal / COLLECT DATA FORMULATE PLANS IMPLEMENT PLANS Earth Science and other Land use Zoning and subdivision regulations information Watershed Erosion and r,edimentation control Background studies Natural resources ordinences Existing land use Hazard mitigation Building end housing code= FIG. 2. Diagram showing the land- Transportation Open space Environmental impact statements Economic Waste management Capital improvement programs use planning process. (After Wil- Political Public facilities Health and sanitation codes liam Spangle and Associates et al. Social Land capability studies 1976). Downloaded from http://egsp.lyellcollection.org/ by guest on September 27, 2021 ASPECTS OF GEOLOGY IN PLANNING