Traditionally, marine infrastructure development is regarded to have a negative impact on the ecosystem in or near which it occurs. As a consequence, a whole industry has been treated as a threat and the ingenuity of companies in this industry was forced to focus on minimizing potential negative impacts. Recent trends are to also consider potential positive spin-offs, by including nature-based components in the designs. In this context, Dutch dredging and marine contractor, Van Oord, launched its Coral Rehabilitation Initiative in 2010. A mobile laboratory, named ReefGuard, was developed, to be operated anywhere in the world for sexual reproduction and rearing corals at a large scale (Van Koningsveld et ah, 2017). ReefGuard is used to initiate 'Coral Engines': large scale nurseries with corals obtained through sexual reproduction as well as from fragmentation. These Coral Engines guarantee the long term and large-scale supply of genetically diverse corals for reef creation and rehabilitation. Having coral 'in stock' furthermore allows reefs to be repaired quickly following harmful events such as hurricanes. The involvement of local stakeholders in its setup and operation foresees in sustainable opportunities for research, education and awareness, and local employment. Since 2010 ReefGuard has been applied in five large scale field applications (Australia 2014, 2015, The Bahamas 2015, 2016, 2017) (Van Koningsveld et al, 2017; Robijns et al, 2018; Schutter et al, 2018) producing thousands of sexual recruits consistently. In 2017 a first Coral Engine was delivered with several tens of thousands newly settled coral recruits, and hundreds of one year old recruits and fragments. This paper explains the concept of the Coral Engine in more detail and shares perspectives for future implementation along marine construction projects across the world. Marine infrastructure projects thus become opportunities for coral reef rehabilitation with essential financial and logistical capacity on site, and often also a legislative requirement for compensation of harmful environmental impact.

People living behind coastal dunes depend on the strength and resilience of dunes for their safety. Forecasts of hydrodynamic conditions and morphological change on a timescale of several days can provide essential information to protect lives and property. In order for forecasts to protect they need be relevant, accurate, provide lead time, and information on confidence. Here we show how confident one can be in morphological predictions of several days ahead. The question is answered by assessing the forecast skill as a function of lead time. The study site in the town of Egmond, the Netherlands, where people depend on the dunes for their safety, is used because it is such a rich data source, with a history of forecasts, tide gauges and bathymetry measurements collected by video cameras. Even though the forecasts are on a local scale, the methods are generally applicable. It is shown that the intertidal beach volume change can be predicted up to three days ahead.