A group of geometric concrete blocks that mimic rock pools have been installed at San Diego Bay in California by eco-engineering company Econcrete to prevent flooding while providing habitats for marine life. The project, named Coastalock, is a coastal defence system with textured and indented surfaces that encourage organisms to latch on and colonise it. It was designed by Econcrete as an alternative to traditional man-made flood defences that typically offer little or no value to underwater ecosystems. Above: Econcrete has designed man-made rock pools. Top image: they have been installed at San Diego Bay Econcrete's installation was carried out with the Port of San Diego corporation on two sites at Harbor Island as part of the area's Blue Economy Incubator, a scheme for trialling new and sustainable marine technologies.