Plumbing reached its early apex in ancient Rome, which saw the introduction of expansive systems of aqueducts, tile wastewater removal, and widespread use of lead pipes. With the Fall of Rome both water supply and sanitation stagnated—or regressed—for well over 1,000 years. Improvement was very slow, with little effective progress made until the growth of modern densely populated cities in the 1800s. During this period, public health authorities began pressing for better waste disposal systems to be installed, to prevent or control epidemics of disease. Earlier, the waste disposal system had merely consisted of collecting waste and dumping it on the ground or into a river. Eventually the development of separate, underground water and sewage systems eliminated open sewage ditches and cesspools.
General employment within the construction sector is sensitive to changes in the economy. But job growth for plumbers is projected to be faster than the average for all jobs. New buildings and residences are being built to comply with stricter water efficiency standards and companies housed in older structures are hoping to retrofit to use more energy-efficient systems, so opportunities are in abundance. According to the Bureau of Labor Statistics, there should be a hiring spurt of 16 percent for plumbers by the year 2026, which translates to about 75,800 new jobs.