The EPA estimates that every year up to 3.5 million Americans get sick from contact with beaches that have been contaminated with raw sewage from overflowing local drainage systems.
Human civilization developed naturally around the ocean. Over the years, seashore houses grew into towering high-rises and small beach towns turned into booming population hubs. Today, one out of every two people lives within 60 kilometers of a coast, and more than 61% of the world’s total GNP comes from regions within 100 kilometers of the ocean. Unfortunately, overdevelopment and the concentration of harmful human activities has caused nearby ecosystems suffer disproportionately.
Agricultural, industrial, urban, and commercial development has significantly altered natural landscapes and connected drainage basins, degrading and destroying key habitats. Since vegetation stabilizes shorelines and filter pollutants, deforestation for agricultural, residential, or industrial settlements has led to more sediment, nutrient, and chemical runoff into coastal ecosystems. Sedimentation suffocates coral reefs, plankton, and aquatic vegetation, which need sunlight to survive. The influx of sewage and land-based pollutants poisons local food webs and changes water chemistry, eventually making it inhospitable to most sea life. Countries in Southeast Asia, the Caribbean, and the Pacific are known to discharge 80-90% of their untreated sewage into the ocean. Studies have shown that beach sand, even in the U.S., contains 100 times more fecal matter than adjacent, contaminated seawater.
Coastal construction projects (e.g. dredging, building piers and shipping channels, and beach renourishment projects) can quickly destroy entire coral colonies and beach habitats, undermining the chances of survival for all dependent fish, bird, and turtle species. Coastal armoring structures in particular, which are built in reaction to erosion and storm surges, inadvertently degrade essential coastal habitats by blocking vital nutrient flow.
Healthy beach vegetation, mangroves, and marshes act as extremely effective natural wave barriers. 15 feet of marsh can absorb 50% of all incoming wave energy, while mangroves can reduce over 66% of wave height—easing erosion and flood risk. Still, more and more coastlines are being covered with protective concrete walls. In the U.S. alone, over 14,000 miles of natural coastline have been covered by concrete walls. If we do not change our current design approach, unsustainable and unregulated development will only make coastal populations more vulnerable to climate change.