Beach Management
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Monitoring IThe efficient and effective management of a barrier beach requires periodic monitoring to assess the health and state of the beach. This monitoring ranges from observations and collection of visual data such as photography, measurements relating to the characteristics off the beach itself, and acquisition of data relating to the conditions affecting the beach such as the wind and wave climate. The Beach Management Manual (Simm et al., 1996) states that these data are necessary for three reasons:
Monitoring should be ongoing as opposed to a one-off survey when coastal defences are installed, and ideally should be initiated prior to the implementation of a management scheme that would result in significant changes to the beach. If this is not the case, then an educated decision as to the form of management methods can not be made, or the likely effects of implementation accurately predicted. A record of adopted shoreline management activities is as important as the data collection itself, enabling future analysis to take changes in beach management into account when interpreting information collected. Monitoring should be undertaken as a co-ordinated
process with other bodies who may have an interest in coastal change
at the site, or the site itself in general. This would include bodies
such as English Nature who may confer a conservation designation
on to the beach. Which data to collect Beach monitoring should not be undertaken without a clear programme and procedures for data collection and an understanding of why the data is required. When determining the monitoring programme the individual character of the beach and the conditions affecting it need to be considered, as well as the context within which the monitoring is occurring. Defra (2001) advise that the development of a monitoring strategy should address a number of issues to determine what should be measured and using what methods:
Simm et al. (1996) advise an initial site visit for familiarisation and to enable an appropriate data-collection programme to be set up. Types of data to be collected, modes of collection and the accuracy/resolution required should be established from the outset, with collection methods which are standardised, repeatable, accurate and cost-effective introduced (Defra, 2001). Information which is readily available in the public domain may be used as part of the dataset and therefore not need to be especially recorded. This may include data from wave and tidal gauges, or climate conditions. The following list briefly describes the types of data which may be collected.
It is only when the information collected regarding these different factors is combined that a full understanding of the beach character and change can be obtained. A programme identifying types of monitoring and methods should be established and adhered to to allow comprehensive and useful datasets to develop. How frequently to monitor A consistent and periodic monitoring regime should be undertaken that enables data and information to be collected at equal time intervals and at the same times each year. This enables a comprehensive dataset to develop and provides enough information for informed decisions to be made. However, some flexibility is needed to allow for adhoc monitoring visits – after severe storms, for example, when useful information may be gathered regarding beach response to extreme conditions. The frequency of monitoring depends upon the trends that are of interest. If, for example, seasonal trends are required, then surveys at 3-monthly intervals are appropriate chosen to coincide with season changes, and carried out at the same times every year. For long-term trends, the more surveys completed per year the better, but the data set needs to be longer to guarantee any accurate results. Therefore the most useful frequency would be at least 3 or 4 times a year over a long period of time, enabling analysis of seasonal changes and long-term trends. Short-term trends and fluctuations require monitoring after storm events, or following a change in conditions or beach management methods. For the most representative view of the effects of storms on beaches, monitoring should be undertaken as soon as practicable following the peak of the storm i.e. the next low tide if possible. Analysis and use of data A clearly defined approach is necessary for the analysis of data, to enable best use to be made of it. This is especially true if collecting data for the identification of long-term trends where monitoring will be continued for a number of years, potentially by a number of different people. The Beach Management Manual (Simm et al., 1996) states that the use of data requires reviewing the information obtained and decided what further monitoring is necessary and whether changes to the management strategy should be instigated. To assure cost-effectiveness and efficiency of monitoring, data should be analysed meaningfully before being used to inform management decisions and be disseminated to the correct audience. Monitoring practices should be reviewed every few years to ensure that they are compatible with the contemporary requirements and priorities, and to allow for the use of cheaper available methods. References
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