Sand and gravel exploitation

In Belgium , sand and gravel exploitation at sea started in 1976 (29.000m³). Over the past few years, the exploitation increased and now the total amount fluctuate around 1.600.000m³ a year. A steadily growing interest in the use of sea sand has been observed, because of the depletion of existing sand quarries on land.

The quality of Belgian gravel not being perfect (the grains are too small), it is mostly sand that is exploited. This sand is used in the construction sector as draining and stabilisation sand or in the concrete industry where it is mixed with other aggregates. For huge infrastructure works, as the construction of a gas pipe line (Zeepipe 1991; Interconnector 1997), there is need for large quantities of sand in a short time. The Flemish Community also uses the sand for beach supplements and coastal protection.

Quantities of sand which have been exploited during the last decade.

The law of June 13, 1969 amended by the law of January 20, 1999 and the law of April 22, 1999 regulates the exploration and exploitation of sand and gravel in certain areas on the Belgian Continental Shelf. Two implementing decrees were published (BS 07.10.04):

• RD of September 1, 2004 (Belgian Official Journal of 10 October 2004, PDF, 14pp, 118KB) as regards conditions, geographic limits and procedures for granting licences, “Procedure decree”.
• RD of September 1, 2004 (Belgian Official Journal of 10 October 2004, PDF, 4pp, 46KB) as regards rules for environmental impact assessment.

In the procedure decree, there are 3 control zones defined, divided in sectors for which a concession can be issued. The accessibility for the control zones is defined:

• sectors 1a, 2c and 3a are open for exploitation all year round;
• sector 1b is only open for exploitation during the months March, April and May;
• sectors 2a and 2b are open for exploitation alternately for a period of 3 years. The consultative commission, established by RD of August 12, 2000 (B.S. 27.09.00) opened sector 2a from March 15, 2005 and so sector 2b is closed for exploitation;
• sector 3b is closed for exploitation as long as the sector is still being used as a dumping site for dredged material.

An exploration zone 4 has been defined. Based on the results of the exploration research, new sectors for exploitation will be defined in this zone. The maximum total surface will be 46 km².

Exceptionally concessions can be issued outside these zones.

The permits for exploiting sand and gravel can be obtained, according to this new law, by submitting a concession demand and an Environmental Impact Study (EIS). This EIS will be evaluated: MUMM evaluates the acceptability of the activity for the marine environment. The evaluation is donated to the Minister responsible for the marine environment, who will give his advice to the federal Minister of Economy. The advice of the Minister responsible for the marine environment is absolute: when the advice is negative, no concession can be issued.

On 17 March 2006 “ZeegraVZW” and “AWZ-Afdeling Kust en Maritieme Toegang” submitted an EIS (in Dutch, with annexes and figures) for the extraction of marine aggregates in the Belgian part of the North sea . The evaluation (in Dutch) and the advice of MUMM were donated to the Minister responsible for the marine environment on July 5 th 2006 . He gave his advice to the federal Minister of Economy who issued the concession (Belgian Monitor 18/08/2006).

The concessions are linked to a compensation used by the authorities for the continuous monitoring of the influence of the exploitation on the marine environment. MUMM uses mathematical models to study the sediment transport disturbed by the exploitations. The study tries to define the conditions of sustainable management and to distinguish the human impact from the natural variability in consequence of storms for example.

Each exploitation vessel must be equipped with an automatic recording system, the so-called black box. This black box can record parameters automatically: identification of vessel, trajectory (the green lines on the figure), date, time, position, speed, status of dredging pumps, etc. MUMM is responsible for managing the recording device and processing the data recorded, on behalf of the PPS of Economy. On the basis of this data it is possible to determine whether the conditions of the concession are respected.

Monthly trajectory of exploitation vessel (green lines) and exploitation sites (red dots).

On international level, the effects of sand and gravel exploitation are studied by the WGEXT Working Group of ICES, from which MUMM is an active member. Also in the framework of OSPAR is stated that member states should follow the ICES directives, because sand and gravel exploitation is a human activity with possible effects for marine ecosystems and habitats.