What ecological effects does a foreshore suppletion, and a beach suppletion, have on the marine ecosystem in the intertidal and shallow surf zone ( ... : This dataset contain the macrobenthic data collected in the subtidal area. Macrobenthos are the biota that lives in the sediment and are retained on a sieve of 1mm. The sampling design for the monitoring is following the BACI-design (Before After Control Impact), with a control area with similar habitat characteristics outside the influence of the suppletion activity. There is sampled before the suppletion and in the following two years after suppletion. In this BACI-monitoring, the seasonal aspect is taken into account, by taking samples in spring (March) and autumn (September). In the subtidal area, three depth strata were determined to investigated the influence of the suppletion outside the suppletion area. Stratum a (between low water line and -2m TAW) is the area were the foreshore suppletion is executed. Stratum b and c are taken respectively the depth zones -3m to -4m and -5m to -6m TAW. The amount of sampling locations was determined by the client and determines 15 points for each sampling moment. ...