Urban farming on a whole new level

Urban farms are cropping up in many cities across the country as a strategy to enhance biodiversity, to increase access to healthy food, and to mitigate storm water runoff. Reporter Ann-Marie Berger shows us how a farm in St. Louis, Missouri has taken this to a whole new level.

TRANSCRIPT

URBAN FARMS ARE CROPPING UP IN MANY CITIES ACROSS THE COUNTRY AS A STRATEGY TO ENHANCE BIODIVERSITY, TO INCREASE ACCESS TO HEALTHY FOOD, AND TO MITIGATE STORM-WATER RUNOFF.

REPORTER ANNE-MARIE BERGER SHOWS US HOW A FARM IN ST. LOUIS, MISSOURI, HAS TAKEN THIS TO A WHOLE NEW LEVEL.

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FARMING -- IT'S NOT JUST FOR WIDE-OPEN SPACES.

THERE'S A NEW, GREENER TREND IN URBAN AREAS -- ROOFTOP FARMING.

AND ON TOP OF THIS TWO-STORY STORAGE BUILDING IN DOWNTOWN ST. LOUIS, FARMERS BEGAN PLANTING ROOTS THIS PAST SUMMER.

SO, THIS AREA THAT YOU SEE IN FRONT OF YOU IS GOING TO BECOME A REAL FUNCTIONING FARM WITH PLANTS IN THE GROUND, SOIL ON TOP OF THE ROOF, AND IT'S GONNA ALSO BECOME PART OF A COMMUNITY GARDEN AS WELL FOR THE CITY.

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FOOD ROOF FARM IS THE VISION OF URBAN HARVEST STL, A COMMUNITY ORGANIZATION WORKING TO TRANSFORM UNDERUTILIZED CITY SPACES INTO PRODUCTIVE LOCAL FOOD SYSTEMS.

THIS BUILDING IS STRUCTURALLY STRONG ENOUGH TO HOLD THE WEIGHT OF THE FARM.

BUT BEFORE SEEDS COULD BE PLANTED AND VEGETABLES COULD GROW, THE ROOF REQUIRED A MAKEOVER.

IT WAS REDESIGNED AND ENGINEERED SPECIFICALLY FOR A GREEN ROOF SYSTEM.

A GREEN ROOF CAN HAVE MANY LAYERS -- ROOT BARRIERS, DRAINAGE AND RETENTION SYSTEMS, AND VEGETATION.

BUT THE FIRST STEP IS WATERPROOFING.

WHAT WE'RE DOING IS PUTTING DOWN A WHOLE NEW ROOF MEMBRANE ON THIS EXISTING BUILDING'S ROOFTOP, AND IT'S A MEMBRANE THAT'S SPECIFICALLY ENGINEERED AND DESIGNED TO BE COMPATIBLE FOR A GREEN ROOF SYSTEM.

SO IT'S A DIFFERENT TYPE OF MEMBRANE.

IT'S A PVC MEMBRANE VERSUS THIS TAR-BASED MEMBRANE.

AND THAT REALLY BECOMES THE FOUNDATION FOR THE FOOD ROOF ALTOGETHER AND HOW WATER DRAINS UNDERNEATH THE FARM ITSELF.

PROPER WATER DRAINAGE.

IT'S CRITICAL.

BUT A GREEN ROOF ISN'T A GREEN ROOF WITHOUT WATER RETENTION.

WHAT YOU'RE SEEING HERE, THIS IS A STORM-WATER RETENTION SYSTEM.

ANTHONY MAYER IS THE CEO OF HANGING GARDENS OUT OF MILWAUKEE, WISCONSIN.

AND HE'S INSTALLING ON THIS FOOD ROOF THE LATEST WATER-CONSERVING TECHNOLOGY.

THESE CUPS ARE FILLED WITH A LIGHTWEIGHT AGGREGATE.

THIS IS A DRAINAGE STONE.

THEY GO ALL THE WAY DOWN TO THE BOTTOM OF THESE CUPS, AND THE CUPS HAVE A FLAT BOTTOM.

THEY DON'T DRAIN IN THE BOTTOM.

THESE CUPS HERE WILL HOLD JUST ABOUT 2 INCHES OF RAINWATER.

AND ANY ADDITIONAL WATER WILL GO DOWN THE SLITS RIGHT HERE AND FOLLOW THESE CHANNELS.

THESE ARE ALL CHANNELS THAT ALLOW WATER TO MOVE THROUGH THE ENTIRE SYSTEM.

WHEN THE SUN BEATS DOWN ON THE ENTIRE SYSTEM, EVEN WHEN THE CUPS ARE FULL, IT'LL EVAPORATE OUT AND THEN ACTUALLY FEED THE PLANTS FROM BELOW.

HELPING TO FEED THE PLANTS IS THE GROWTH MEDIA.

SIMPLY PUT, IT'S THE CAREFULLY ENGINEERED SOIL PRODUCT THAT MIMICS DIRT, SUPPLYING PLANTS WITH NUTRIENTS, AIR, AND WATER.

THE FDA IS SAYING, YOU KNOW, 'EAT YOUR FIVE TO SEVEN, FIVE TO NINE VEGETABLES A DAY AND FRUITS,' BUT THEY'RE THE MOST POLLUTED OF ALL, YOU KNOW, OF OUR FOOD.

AND SO USING THIS WILL GIVE THEM THE RIGHT NUTRIENTS WITHOUT THE POLLUTION, THE PESTICIDES, AND THE CHEMICALS THAT GO INTO IT.

THE GROWING MEDIA ON FOOD ROOF FARM IS CALLED THE WaterGrip BROWNIE, AND IT'S HALF THE WEIGHT OF NORMAL GROWING MEDIA.

IT'S MADE OF AN ORGANIC MIX OF PROPRIETARY INGREDIENTS THAT ACTS LIKE A SPONGE, PULLING WATER FROM THE CUPS AND FEEDING THE ROOTS OF THE PLANTS.

YOU JUST PUT A LITTLE HOLE IN IT.

YOU POP IN YOUR PLANT.

AND USING CONSERVED RAINWATER REDUCES THE IRRIGATION NEEDS BY 50% TO 75%.

THERE IS NO GROWING MEDIA ON THE MARKET THAT HAS THE SAME WATER-HOLDING CAPACITY AS THIS SYSTEM DOES.

AND SO, WHEN THIS HOLDS 2 INCHES OF WATER, I MEAN... JUST IN ITSELF, YOUR NORMAL GROWING MEDIA, YOU KNOW, MIGHT GET YOU AN INCH AND A QUARTER.

BUT THIS GREEN ROOF SYSTEM DOES MORE THAN HELP WATER THE PLANTS.

IT LESSENS THE AMOUNT OF WATER THAT FLOWS THROUGH THE CITY'S STORM AND SEWER DRAINS, MITIGATING STORM-WATER MANAGEMENT AND POLLUTED RUNOFF IN ADJACENT RIVERS, STREAMS, AND LAKES.

IN THEIR FIRST GROWING SEASON ON JUST A 1/5-OF-AN-ACRE ROOFTOP, FOOD ROOF FARM PRODUCED 62 VARIETIES OF FOOD CROPS AND MORE THAN 1,000 POUNDS OF FOOD, MOST OF WHICH WAS DONATED TO A LOCAL HOMELESS SHELTER.

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