OFF-ROAD VEHICLE USE IN THE COASTAL ZONE:USING GIS TO PROVIDE DECISION SUPPORT TO MANAGERS

L. Celliers (1), T. Moffett (2), B.Q. Mann (1), P. Pradervand (1), N. James (1)

(1) Oceanographic Research Institute, Marine Parade (ZA)
(2) Coastal Management Unit, Department of Agriculture and Environmental Affairs, Pietermaritzburg (ZA)

Introduction
KwaZulu-Natal (KZN) is one of four coastal provinces in South Africa (Fig. 1). This province has a warm-subtropical climate and a coastline of spectacular natural beauty. The coastal zone include elements such as estuaries, mangrove forests, coastal dune forests, sandy beaches, rocky shores and coral reefs. Recreational opportunities associated with the coastal zone are numerous and activities such as ecotourism are booming. Governance of the province is seated in a provincial legislature and responsibilities are often devolved to local authorities such as municipalities or Ezemvelo KwaZulu-Natal Wildlife, a parastatal conservation organisation.

Figure 1. The province of KZN, the coastal municipalities and major coastal conservation areas.

The use of off-road vehicles (ORVs) in the coastal zone is a popular activity along the coast of South Africa and vehicles have become a common sight on beaches. Beach driving has become associated with a number of recreational and tourism activities in the coastal zone. Beach driving allows fisherman convenient access to more remote areas of the KZN coastline and is essential for launching trailered boats from the numerous boat launching sites in the province. It has also become part of the ecotourism industry, particularly in the Greater St Lucia Wetland Park (GSLWP), where it is associated with activities such as turtle watching and birding.

Figure 2. Off-road vehicle use in the coastal zone of KZN during 2001. a) ORVs counted on beaches, expressed as number of vehicles per shore patrol, and b) Estimated number of annual boat launches from sites along the coast. Colour coding the same as for Fig. 1.

Both fishing from shore and from boats has a significant impact on the resources of the coastal zone and therefore beach driving, which allows access to these resources, needs to be controlled. Furthermore, people have an inalienable right to the opportunity to escape from the artificial impositions of others, and certain areas must be guaranteed to be free from motor vehicles [1]. Beaches are important open-air recreation sources for most coastal town-dwellers and are regarded as healthy, open places [2]. Consequently, designating specific beach areas where ORVs may be used, affects a number of users and user groups and a careful, inclusive approach are needed to accommodate all users when designating these areas. This follows the principles of integrated coastal zone management that dictates that coastal use be defined according to a spectrum of variables.

Scientific studies elucidating the effects of ORVs in the diverse environments of the coastal zone have been scant [3-6]. However, existing studies show that off-road vehicles influence the fauna and flora of beaches negatively, while also contributing to the destabilisation of coastal dunes (see review by [7]). Physical effects of ORVs on beaches include changes in the density of soil bulk, and erosion.

The legislation
Recently, the Minister of Environmental Affairs and Tourism passed new regulations to protect the interest of civil society and the environment of the coastal zone. The control of vehicles in the coastal zone of South Africa (Regulation No. 1399 of 2001) became effective on 20 January 2002 in terms of section 44 of the National Environmental Management Act (NEMA; No. 1-7 of 1998). The new regulations make provision for among others:

• The declaration of recreational use areas (RUAs) in the coastal zone within which vehicles may be used for recreational purposes.
• Licensing of boat launching sites (BLSs) from which recreational and commercial small-craft may launch.

Dealing with such matters in KZN, is the Department of Agricultural and Environmental Affairs (DAEA), and more specifically the Coastal Management Unit (CMU), the provincial government authority.

Objectives
The objectives of this study were to provide scientific decision support to the provincial authorities designated to deal with implementation of the regulations by addressing the following:

• Collate and map information relevant to the use of ORVs in the coastal zone of KZN as specified by the new regulations.
• Provide scientific and social justification for the siting of ORV use areas (RUAs and BLSs).
• Define the size, location and usage of potential RUAs.

Methods
A panel of experts comprising scientists and coastal zone managers were convened as a RUA Task Team. This panel identified seven coastal attributes or features with spatial dimensions that immediately disqualified an area from being considered for a RUA (Table 2). Spatial data relating to the seven exclusions were either extracted from existing data sources or were created as new overlays for the GIS project depicting the KZN coast.

Table 2. Seven attributes or features of the coastal zone of KZN that would disqualify such an area from being considered as a potential RUA.

EXCLUSION FEATURES
1. Any area outside the hard sand of the intertidal zone.
2. Fragile, rare, relict or vanishing vegetation.
3. Wildlife sanctuaries and reserves.
4. Unsuitable physical attributes of beaches or natural barriers.
5. Areas of fragile natural features or scientific interest.
6. Areas of potential beach user conflict.
7. Unidentified or unexplored key ecological processes.

A model of potential RUAs in KZN was created with a GIS, using 100 m grid cells along the coast. Each 100 m cell was assigned a value of 0 or the sum of the grid cell value depending on whether it intercepted, or was within 100 m of an exclusion zone (e.g. an estuary mouth). A zero value was awarded if there were no underlying exclusion features. The cumulative effect of multiple exclusions in one coastal block was not considered and once a cell was designated a value greater than 1 it was considered to be exempt from being considered for a RUA. Once areas exempt from RUAs had been identified, the remainder of the coast was divided into coastal segments (³2 km) which were considered potential RUAs. The percentage of total coastline protected from ORVs was then calculated.

Figure 3. Coastal exclusion features relating to the siting of RUAs along the coast of KZN. Green cells represent potential RUAs.

Following the identification of potential RUAs according to the above mentioned exclusion features, a number of other important factors need to be addressed by a full environmental impact assessment as part of the application for a RUA. These other considerations include possible future marine protected areas, areas where subsistence fishing is prevalent, historical beach driving areas, and aesthetic value etc.

Results
The potential RUAs identified using this approach are shown in Fig. 4. The statistics pertaining to these potential RUAs are shown in Table 2.

Figure 4. Potential RUAs for the coastline of KZN, identified using seven exclusion characteristics.

Table 2. Summary of a potential RUA network using the current KZN provincial model for the designation of RUAs.

Total length of KZN coast (km) Total distance covered by potential RUAs (km) Mean length of potential RUAs (km) Maximum length of a potential RUA segment (km) Minimum length of a potential RUAs segment (km) Percent of KZN covered by RUAs

562 239 7.3 28.4 2.0 42.6

Conclusions [8, 9]
The following conclusions were reached following implementation and use of this system:

• Provides a logical decision support system that will prevent ad hoc applications from being considered.
• Good quality spatial data and sufficient human capacity to manipulate data in the GIS is essential.
• The model, by virtue of the seven exclusions, was criticised for being inflexible and in some cases being unreasonably stringent.
• Does not allow for subjectivity or biases, and provides a socially and scientifically justifiable motivation for not considering certain coastal areas suitable for ORV use.
• Although the guidelines were developed to site RUAs in KZN, the principles are sufficiently generic to be applied to the rest of the coastal provinces of South Africa and could potentially serve as a national model for the siting of RUAs and other similar areas.
• Integrated coastal zone management dictates that coastal use be defined according to a spectrum of variables. Similarly, RUAs influence a diverse number of users and user groups and a careful inclusive approach in their designation is needed to address all the concerns.

Future uses of the coastal GIS.
Currently the responsible siting of areas related to ORV use in the coastal zone is hampered by a lack of knowledge of the associated resources (impacts on beach fauna and flora, state of fish stocks, etc ). However, as the limitations on critical parameters are reduced by research and data collection, so will our ability to manage human impact increase. A coastal GIS will be essential to correlate and visualize the variety of data (scientific and socio-economic) that relate to the coastal zone in order to ensure wise human development in this sensitive environment (Fig. 5).

Figure 5. Potential future uses of a coastal GIS. a). Monitoring of ORV use in the coastal zone. Bar graph represent ORV numbers in a number of management zones along the coast, and b) Siting of boat launch sites according to the status of the extractive marine resources that this activity is primarily based on. The blue buffers around existing launch sites represent the operating areas based on a maximum operating distance of 30 km from the launch site, while the reefs most impacted by fishing activities from launch sites are shown in red.

Acknowledgements
The Recreational Use Areas Task Team and the organisations they represent are gratefully acknowledged for the time spent discussing and reviewing the many drafts of this document. The South African Association for Marine Biological Research and the Department of Agriculture and Environmental Affairs is thanked for their financial support.

---

References

1. National Parks Association of New South Wales Inc. Motor vehicles in natural areas. http://speednet.com.au/~abarca/NPApol01VEHICLES.htm . 2002.
2. Bird ECF. Beach management. Chichester: John Wiley & Sons Ltd., 1996 (281 pp.).
3. Brodhead JMB, Godfrey PJ. Effects of off-road vehicles on plants of a northern marsh. Report UM/NPSCRU No. 33. 1979.
4. Leatherman SP, Godfrey PJ. The impact of off-road vehicles on coastal ecosystems in Cape Cod National Seashore: an overview. Report UM/NPSCRU No. 34. 1979.
5. Van Der Merwe D, Van Der Merwe D. Effects of off-road vehicles on the macrofauna of a sandy beach. South African Journal of Science 1991;87:210-3.
6. Els S, McLachlan A. A survey of off-road vehicle use in the Eastern Cape. Report 21, SAB Institute for Coastal Research, Port Elizabeth, South Africa, 1990. 38pp.
7. Van Der Merwe D. The effects of off-road vehicles (ORV's) on coastal ecosystems - a review. Report 17, SAB Institute for Coastal Research, Port Elizabeth, 1988. 64pp.
8. Celliers L, Moffett T, James NC, Mann BQ. A strategic assessment of recreational use areas for off-road vehicles in the coastal zone of KwaZulu-Natal, South Africa. (submitted to Ocean and Coastal Management).
9. Celliers L, Moffett T, James NC, Mann BQ. A strategic assessment of recreational use areas for off-road vehicles in the coastal zone of KwaZulu-Natal, South Africa. ORI Unpublished Report 209, 2002. 13p.