What Is Sewage Farm? Advantages and Disadvantages Of Sewage Farm
What Is Sewage Farm?
Sewage farms utilize wastewater for watering crops and fertilizing farmland, particularly in regions with limited freshwater sources and warm, dry climates. Bacteria and microbes convert suspended solids into humus, providing essential nutrients for crops.
Though many developed nations now use conventional sewage treatment facilities, sewage farming remains a cost-effective solution for some developing countries. It should not be mistaken with other methods of sewage disposal like infiltration basins or subsurface drains.
History Of Sewage Farm
In the past, household sewage was collected from cities and towns and taken to nearby farms as a precursor to modern sewage treatment systems. During the Middle Ages, this was done using hand-carried buckets, but as populations increased during the Industrial Revolution, sanitary sewer systems were constructed.
These systems used a network of pipes and pumps to transport sewage beyond city limits to largely rented farmland where the sewage would flow into the ground. Berlin once had 20 sewage farms spanning 10,000 hectares.
In Wales, sewage farms were a common means of sewage treatment as the population grew in towns during the Industrial Revolution and local cess-pits became insufficient. Initially, sewage was sent to nearby rivers through trunk sewers, but as populations continued to grow, sewage farms were established.
Some of these farms were still in use until the late 20th century when it was realized that sewage contaminated with infectious pathogens and industrial waste was not always safe for use as fertilizer. Modern sewage farms are now combined with sewage treatment plants to irrigate land with treated sewage (reclaimed water).
Some types of raw sewage can also be used on a sewage farm or filtered through constructed wetlands.
Advantages Of Sewage Farm
Sewage farming makes use of wastewater for irrigation instead of letting it go to waste. The organic solids and nutrients in sewage can enrich soil and agricultural products, instead of polluting natural water bodies.
Pumping sewage to the farm may be the only necessary step, provided the village isn’t located higher than the farm.
Disadvantages Of Sewage Farm
When fields are irrigated with sewage, there is a risk of polluted runoff occurring if the amount of wastewater and precipitation exceeds the capacity for evaporation and percolation.
Sewage is generated continuously, but irrigation only takes place during dry weather when temperatures are suitable for plant growth. Over-irrigation can cause the soil to become contaminated and unpleasant.
In arid climates, sewage can be stored temporarily in ponds during non-growing seasons, but this can lead to unpleasant odors and mosquito problems.
Protecting crops from direct contact with sewage can be difficult, especially with ground crops and spray irrigation, as there is a risk of pathogen transfer through vectors such as birds and insects.
This is especially true for fruit trees grown in surface ditches where transfer of pathogens from sewage to edible fruit is more likely.