Newlyn

Newlyn, Cornwall, United Kingdom

Implementing nature-inclusive design to deliver multiple benefits. Situated on the shores of Mount’s Bay in southwest England, Newlyn’s heavily developed coastline relies on hard seawalls and breakwaters to manage flood risk and has limited foreshore space to implement nature-based solutions, such as dune restoration. With a fixed line of hard defenses competing with sea levels at the cost of intertidal habitat, innovation to protect coastal communities and biodiversity is needed. The Newlyn Coastal Research and Development project, a partnership between the Environment Agency and Kier and Atkins, trialed 88 eco-armor units around the existing breakwater to investigate the ability of this innovative technology to enhance intertidal biodiversity while fulfilling its primary function as coastal armor. This pilot was among the first to use the technology, typically used in moderate and subtidal environments, in an intertidal, high-energy setting. Four suppliers were used: Exo Engineering, ECOncrete, ARC Marine, and JP Concrete. The low-carbon element of the concrete mixes saved 41 tonnes of embodied carbon in material alone compared to standard CEM I ordinary Portland cement mix concrete units. The project received the Concrete Society’s Devon & Cornwall Region Sustainable Concrete Award in 2022 for its innovative practices.

Article Cover: Eco-armor units from four suppliers were evenly distributed around an existing rock breakwater to maximize learning opportunities from the project. (Photo by Environment Agency)

Producing Efficiencies

The eco-armor units, which have been evenly distributed around the apron of the existing rock breakwater to maximize performance learning, feature low-carbon concrete mixes, have an altered pH similar to seawater, and make use of local aggregate, supporting a local circular economy. One aggregate is a byproduct from a quarry, which is regulated if excess aggregate enters the local watercourse. Using this byproduct reduces pollution risk. Growth of marine species on the units can create a carbon sink while protecting the breakwater asset. Radio frequency ID tags and scanners are used to monitor specific units without removing growth.

Using Natural Processes

Surface texturing, water retention features, and an altered pH to match that of seawater encourage the growth of marine flora and fauna on the units. This delivers biodiversity enhancements, providing a space for the migration of coastal species in a location suffering coastal squeeze. Flora will sequester carbon to the point that the project could become carbon neutral in the future. Natural environments have been enhanced by providing space for rocky shore species to thrive and migrate to. The eco-units will be monitored for at least five years to investigate asset condition and habitat creation, with results considered in future coastal projects.

Nooks and crevices have been designed into the eco-armor units to provide shelter for marine life. The original granite rock breakwater has been in situ since 1992 and had supported very little marine life due to its smooth characteristic. Since completion of the pilot in February 2023, growth of algae on the rocks has been observed for the first time, along with attached bivalves.

(Photo by Environment Agency)

Broadening Benefits

This project has saved tonnes of carbon dioxide in material due to the low-carbon concrete mixes. Some units comprise local aggregate from rock-quarrying byproduct like granite dust, diverting a pollution risk. The use of native materials means local marine species are more likely to grow on the units. Though suppliers were not local, they agreed to fabricate within the southwest region, significantly reducing transport carbon costs. This pilot has engaged the community around coastal-change messaging, sustainable coastal defenses, and habitat-restoration opportunities. School children have participated in an educational roadshow and a coastal-themed art competition.

Each unit is around 4.8 tonnes and 1.3 cubic meters, providing new intertidal habitat as well as protection to existing infrastructure.

(Photo by Environment Agency)

Promoting Collaboration

With a widespread team, online meeting platforms and data-sharing sites were used to ensure accessibility and eliminate travel time and carbon. Valuable community engagement was achieved via advertised daytime and evening events as well as multiple feedback methods. Concern was raised about impact to a heritage feature, resulting in an update to the construction methodology and a heritage survey. Units from each supplier were evenly distributed around the breakwater, ensuring comparable monitoring. Suppliers demonstrated “bigger-picture” culture by offering to fabricate at each other’s yards and collaborating while being industry competitors.

Designs incorporated water-retaining features, identified as a key factor in encouraging colonization by marine species.

(Photo by Environment Agency)

Rough surface texturing increases surface area for accumulation of biofilm, promoting succession and increasing intertidal biodiversity.

(Photo by Environment Agency)