if you take a look at concrete
structures like breakwaters or sea walls
the water around them is often clear
that's not actually a good thing because
it means there's no life marine species
are actually most abundant in coastal
areas but it's also whereas humans
prefer to live too so when we build here
we drive away marine life the concrete
in the marine world has a lot of
additives a lot of chemicals and some of
those materials are actually leaching
out and they're actually prohibiting
marine life to thrive to keep developing
without any regards to natural
communities there is a tilting point
from each beyond we cannot really go
back
in the coastal city of Tel Aviv an
Israeli startup wants to revolutionize
our urban coastlines their sea defenses
are transforming lifeless man-made
structures into teeming ecosystems they
do this by replacing standard concrete
with their own special cement formulas
as opposed to regular cement based
concrete concrete includes certain
elements that enhance the growth of
marine flora and fauna of plants and
animals our ad mix which is kind of our
secret sauce is basically kind of
sealing the concrete making it less
aggressive for the marine environment
that once we added we enable life to
flourish in the lab the team run tests
to identify what mixes will work best
for marine life so we take really ice
cube size concrete slabs of different
compositions and we put larvae 20 30 50
we need to have a lot of replicates
we're geeky scientists so we have to
have a lot of replication and controls
and then within a few days or just a few
weeks we can get an answer on their
preference so obviously if they die they
have a very low tolerance to that
specific concrete mix design and if they
thrive or defer we can quantify that
very quickly key concrete says it
typically sees double the biodiversity
of regular great concrete from fish and
sea caterpillars on their armor blocks
to crabs on these tidal pools that sits
on the shoreline this unit holds water
during the low tide so it's always moist
and therefore it has a very comfortable
habitat for crabs and sea anemones and
sea stars etc these pools have been here
for less than three months and this is
already what you can see it's covered
with life see the rock around it which
has been here for probably 10 20 maybe
even more years only has a thin layer of
green algae and that's it
as well as the composition of the cement
mix the concrete designs its products
specifically to the marine environment
that will be deployed to create niches
for endangered species or to develop
nurseries like these oyster beds the
final part of the equation is creating
complex surface textures to mimic
natural rock or coral an environment
that helps anchor young organisms when
concrete elements are being cast the
typical goal is to have a very slick
surface very very smooth the idea is to
get the water to flow right across it
when we're designing e concrete with a
rough surface we want to do the complete
opposite we want to slow the water when
they are crossing the structure so that
the larva can actually adhere and attach
to the surface the concrete has to offer
its kinds more than just ecological
credentials over time they've discovered
that creating hospitable habitats for
marine life adds another advantage one
that is surely hard to ignore we've seen
evidence to the fact that the growth of
the organisms on the concrete create
kind of a layer of Defense just the
addition of weight we can actually gain
stability and strength over time this is
the let's say the the unit when we put
it in the water and this is after a year
in the water and what you can see here
is all the oysters are completely
covering it we designed the units so
they can withstand the forces and
perform in terms of structural
performance but they can also be a
backbone for ecological enhancement the
company tests its miniature designs in
tanks full of real seawater rocks plants
and animal life from around the world
what we're looking for is the
accumulation of calcium carbonates on
the surface of the concrete of bight of
different mixes in different designs
this is the process we collect biogenic
build up with time begin a buildup of
calcium carbonate that is sourced for
marine organisms on the surface of the
concrete and we actually encapsulate the
concrete with a natural rock so when the
organism died in case of the coral it
will die and then another
Paul will sit on end and that's how a
reef is ruined the hope that our
man-made structures could become
stronger over time also means better
economics the unit's require less
maintenance and could therefore stay in
the water for longer a concrete dough is
just a few years old so it needs more
time to wreak wanta fie the longevity of
its products but the company are certain
their products are better for the
environment and not just in terms of
improving biodiversity or kind of trying
to offset some of that immense carbon
footprint of the concrete industry
construction is responsible for about 11
percent of global carbon emissions by
adding a biological crust to their
products the concrete prevents some co2
from being released into the atmosphere
for every kilogram of calcium carbonate
being created by those marine organisms
we're offsetting a hundred and twenty
grams of co2 so think about building a
poor infrastructure or a city waterfront
that is an active carbon sink I think
that's the great advantage of the
technology
you