Understand your impact

When we build along our coasts and ocean floors, we create an impact on our environment. We have the opportunity to choose if that impact revives or deteriorates our environment.  With ECOncrete, we can calculate the positive impacts projects make. 

While effects on the environment are many, we chose to focus on measuring three positive impacts of the biodiverse ecosystems that grow on ECOncrete for three types of projects. You can multiply your impact by the intended lifetime of a project (40-120 years) to get a fuller understanding of what it means to replace traditional Portland-cement based concrete with ECOncrete.

All data was normalized to represent an annual value per linear meter, and based on rigorously gathered data from experiments and continuous monitoring of biological recruitment to ECOncrete’s infrastructures. The estimates for values are based on the biologically available surface area per meter of a given type of solution. Biologically available surface area means the area available for different marine species, like oysters, coralline algae, and tubeworms to settle on a given type of infrastructure unit. These species are the source of the positive environmental impacts we see as a result of installing ECOncrete. 

The three types of projects are:

Seawalls, where one infrastructure unit is 1 meter wide and 7 meters tall. This results in 7 meters of biologically available surface area per linear meter.

Pier piles, where one infrastructure unit is 80 centimeters in diameter and 6 meters tall. This results in 15 meters of biologically available surface area per linear meter.

Shoreline protections is an average of different revetment and breakwater solutions, where one unit includes 15 pieces of infrastructure in 1 meter wide strip. This results in 52.5 meters of biologically available infrastructure per linear meter. 

Ecosystem services

Ecosystems provide us with a wide range of services, like climate regulation, water purification, flood protection, food, aesthetics, and recreational value. These services depend on natural capital, or the world’s stocks of natural resources like water, living things, soil and air. With our coastal construction, we can deplete or regenerate our natural capital and the services it provides.

The marine species that grow on ECOncrete create the basis for a biodiverse and productive ecosystem. Species like oysters, for example, are known “ecosystem engineers;” as they grow, they become a critical ecological stepping stone for additional organisms to live on and around a structure. In this way, oysters and other species help create an ecosystem on ECOncrete, building the base for species like fish, octopuses, or crabs to thrive, and providing services to humanity as well. 

Various methods can be used to assign a dollar value to ecosystem services. Although we believe marine ecosystems are priceless, the results in our calculator are intended to provide an indicative value of marine ecosystems, rather than their “true” value. We based the calculator’s dollar value estimate on the “Ecosystem Services Valuation Database (ESVD),” which contains 4,092 ecosystem service values based on 693 studies; of those, 2,917 values were standardized to international $ per hectare per year.

For our calculation, we used and converted mean standardized values per ecosystem biome of coastal systems (int$/meter or foot/year; 2020 price levels). We used biome value, as the value of ECOncrete goes beyond the primary ecosystem services ECOncrete infrastructure provides (wave attenuation, flood protection, erosion control) and extends into the living biome that grows on ECOncrete. To encompass both of these considerations, we chose applicable ecosystem services which ECOncrete directly provides and can be equated to those provided by natural ecosystems: genetic resources, maintenance of genetic diversity, maintenance of life cycles of migratory species, moderation of extreme events, erosion prevention, and climate regulation. One meter of ECOncrete deployed in the ocean produces $1.36 in ecosystem services per year, and one foot produces $0.13 every year, in 2020 US dollars.

Carbon sequestration

Our oceans act as carbon sinks—reservoirs that store atmospheric carbon dioxide. In the same way that trees take up CO₂ from the air and store it, marine organisms with calcitic skeletons also store the greenhouse gas. Organisms like oysters, tubeworms, barnacles, and more absorb carbon dioxide and calcium from the water, and use it to build their shells, or skeletons. 

The potential for carbon storage in calcitic (the carbonate mineral of calcium carbonate) skeletons of marine organisms is huge. One calcium carbonate (CaCO₃) molecule (composed of one calcium atom [40.078 g/mole], one carbon atom [12.011 g/mole] and three oxygen atoms [47.997 g/ mole]) has a molecular weight of 100.086 g/mole. Thus, in every 1,000g of CaCO₃, 120g of carbon are stored. 

To equate this value to ECOncrete’s infrastructure, we referred to ECOncrete’s peer reviewed research, which found that in a temperate Mediterranean Sea environment, 659.51g of calcium carbonate were deposited per square meter of infrastructure per year, and in a tropical Red Sea environment 249.72g of CaCO₃ were deposited by marine organisms, with maximum values reaching 1000g/m²/year. This rate corresponds to a maximum storage of 120g of carbon dioxide for every square meter of ECOncrete infrastructure annually. Grams were converted to metric tonnes, and tonnes of CO₂ were also presented as the equivalent number of trees (when one adult tree has the capacity of storing 20-21kg of CO₂ per year).   

Water filtration

Many sedentary organisms that grow on hard marine surfaces (like rock or concrete) are filter feeders like mussels, clams, and barnacles. There are fundamental principles that characterize the roles of filter feeders in ecosystems, such as contributing to the reliability and stability of an ecosystem’s functioning, creating habitat heterogeneity, accelerating chemical cycling, and improving water quality. Filter-feeders remove various particles of a broad range of sizes from the water column in order to eat. Different species have different filtration rates that are presented in units of liter/gram/hour.

To calculate the potential for water filtration with ECOncrete infrastructure, we based our calculations on ECOncrete’s previous studies (2014, 2018, Case Studies) and monitoring data to determine the filter feeding species that grow on ECOncrete. We then averaged the number of filtering species that would accumulate on a square meter of ECOncrete infrastructure per year. The filtration rates of a few of the species which grow on ECOncrete (unfortunately, not all of them have been studied!) are found in the literature (see below). Values are presented as liters (or gallons) of seawater per year (per meter/foot of ECOncrete infrastructure). We also converted the liters/gallons value to Olympic pools filtered per year (2.5 million liters/ 660K gallons per pool), just because it’s amazing!