As the world population grows steadily so does the consumption of meat and as a result, the world-wide production of livestock. Whereas once livestock was left to graze in the fields, today we are faced with an increase in factory farms, where thousands of animals are kept in overcrowded areas where they produces massive amounts of animal waste on relatively small plots of land. When too much waste is produced in one place, there’s no safe, cost-effective way to either use it productively or dispose of it. The problem of livestock waste will never end so long as we rely on industrial farming to produce our food.
The USDA estimates that more than 335 million tons of “dry matter” waste is produced annually on farms in the United States, representing almost a third of the total municipal and industrial waste produced every year. Moreover, animal feeding operations annually produce about 100 times more manure than the amount of human sewage sludge processed in US municipal wastewater plants. One dairy farm with 2,500 cows produces as much waste as a city with around 411,000 residents.
If properly treated animal waste could be a valuable resource, however most of the improperly treated waste is either washed or dumped into rivers and lakes, while the rest is absorbed by the soil and crops. With animal waste containing high levels of pathogens such as salmonella, e-coli and fecal coliform, the water becomes highly contaminated.
Manure is usually stored for many months, often in giant outdoor pits known as lagoons. As it decomposes, the manure emits harmful gases such as ammonia and hydrogen sulfide. Meanwhile, these lagoons can leak or rupture, polluting the surrounding soil and water systems. Even without leaks, manure lagoons are so fragile that major storms often result in overflows. Perhaps most famously, in 1999, the majority of North Carolina’s manure lagoons spilled over into waterways during Hurricane Floyd, leading to widespread water contamination.
Animal Waste Pathogens
With animal waste containing high levels of pathogens such as salmonella, e-coli and fecal coliform the water becomes highly contaminated
There are an estimated 19 billion chickens currently being bred
The number of cows are estimated at 1.4 billion
Sheep and pigs
The estimate for sheep and pigs is approximately 1 billion