Hydraulic fracturing, or fracking, faces growing opposition because of a convergence of documented harms: contaminated drinking water, measurable health risks for nearby residents, earthquake activity linked to wastewater disposal, massive water consumption, and methane emissions that undermine its supposed climate advantage over coal. Six U.S. states have enacted bans or moratoriums, and several countries including France and Germany have taken similar steps. Here’s what the evidence actually shows.
Drinking Water Contamination
The most direct concern is what fracking does to water supplies. Each well requires between 1.5 million and 16 million gallons of water mixed with roughly 1,000 different chemicals, then injected underground at extreme pressure. What comes back up, called produced water or flowback, carries those chemicals plus substances picked up from deep rock formations: arsenic, mercury, barium, radioactive isotopes, and a group of organic compounds known as BTEX (benzene, toluene, ethylbenzene, and xylene).
The U.S. EPA has identified damaged well casings and faulty cement seals as the most likely cause of drinking water contamination. When the steel and concrete lining of a borehole fails, fracking fluids and methane can migrate into surrounding rock and groundwater. Surface spills from leaking containers and pipelines create a second pathway. In contaminated areas near drilling operations, groundwater samples exceeded federal safe drinking water limits for benzene in 90% of samples tested. Methanol appeared in 29% of all samples from one study of active extraction areas.
Four distinct contamination routes have been identified by researchers: leaking gas wells that allow chemicals and stray gas into shallow groundwater, inadequately treated production water discharged into surface waterways, buildup of toxic and radioactive compounds in river and lake sediments, and sheer overuse of local water resources.
Health Risks for Nearby Residents
People living close to fracking operations face elevated health risks, with pregnant women and their babies among the most studied populations. A California study covering nearly a decade of birth records found that rural mothers living near fracking sites had 74% higher odds of delivering a low birth weight baby compared to those living farther away. Babies born to these mothers weighed an average of 73 grams less. The odds of a baby being small for gestational age were 68% higher.
Beyond birth outcomes, roughly 120 of the chemicals used in oil and gas operations are known or suspected endocrine disruptors, meaning they interfere with the body’s hormonal systems. Laboratory testing of 12 commonly used fracking chemicals found that 11 blocked estrogen receptors and 10 blocked androgen receptors in human cells. Naphthalene, a chemical used in fracking fluid that has been detected in air and water near drilling sites, has been linked to altered hormone levels, reproductive abnormalities, and impaired sexual development in animal studies. These aren’t theoretical exposures: naphthalene and other endocrine disruptors have been measured in environmental samples collected near active operations.
Worker Safety
Fracking workers face a hazard that wasn’t even recognized until researchers from the National Institute for Occupational Safety and Health investigated it: dangerously high levels of silica dust. The sand pumped underground to prop open rock fractures is crystalline silica, and the mechanical handling of millions of pounds of it per well generates clouds of fine, breathable dust. When NIOSH collected 111 air samples from workers at 11 fracking sites across five states, every single site exceeded occupational health limits. Some exceeded safe exposure levels by more than ten times. Prolonged silica exposure causes silicosis, an irreversible lung disease, and increases the risk of lung cancer.
Earthquakes From Wastewater Disposal
Fracking itself rarely triggers large earthquakes, but the wastewater it produces does. The billions of gallons of contaminated water that flow back from wells are typically disposed of by injecting them into deep underground wells. This practice has triggered a dramatic increase in seismic activity across the central United States. Oklahoma, which averaged 24 earthquakes of magnitude 3.0 or greater per year from 1973 to 2008, recorded 688 in 2014 alone. From 2014 through 2017, Oklahoma experienced more significant earthquakes than California.
The largest documented injection-induced earthquake was a magnitude 5.8 event in central Oklahoma in September 2016. Four earthquakes of magnitude 5.0 or greater struck Oklahoma, with three occurring in 2016. Additional induced earthquakes between magnitude 4.5 and 5.0 have hit Arkansas and Kansas. These are not minor tremors. A magnitude 5.0 earthquake can crack walls, break windows, and damage infrastructure. Of roughly 40,000 oil and gas wastewater disposal wells in the U.S., only a small fraction have caused concerning seismicity, but the consequences when they do are serious and widespread.
Methane Emissions and Climate Impact
Natural gas has been promoted as a “bridge fuel” between coal and renewables because burning it produces less carbon dioxide. But that argument depends on how much methane, a potent greenhouse gas, leaks during production. Methane traps roughly 80 times more heat than carbon dioxide over a 20-year period, so even small leaks can erase the climate advantage.
Satellite measurements of the five most productive U.S. shale basins found methane leakage rates ranging from 1.2% to 3.9% of total production. The threshold at which gas loses its immediate climate benefit over coal is about 3%. Four of the five major basins measured below that line, but the Anadarko Basin in Oklahoma leaked at 3.9%, roughly matching the break-even point for a 20-year climate horizon. Turkmenistan’s massive gas fields leaked at 4.1%. These numbers mean that in some of the world’s biggest production regions, fracked gas is no better for the climate than coal, and possibly worse over the next two decades.
Massive Water Consumption
Fracking is extraordinarily water-intensive. A single horizontal well in the Marcellus Shale of Pennsylvania requires an average of 4.5 million gallons. In Texas’s Haynesville Shale, that figure rises to 5.7 million gallons. Canada’s Horn River formation averages 15.8 million gallons per well. In drought-prone regions like west Texas, where fracking competes with agriculture and municipal supplies for increasingly scarce water, this consumption strains resources that communities depend on. The water that comes back from a well is too contaminated with chemicals, heavy metals, and radioactive material to be easily recycled, so the vast majority of it becomes waste requiring permanent underground disposal.
Property Values and Local Costs
Homeowners near fracking sites bear direct financial losses. A Duke University study in Pennsylvania found that homes relying on well water lost an average of 13.9% of their value when a shale gas well was drilled within one kilometer. That translated to roughly $30,000 per home. These homeowners also face costs the study didn’t quantify, like whole-home water filtration systems purchased as a precaution after drilling begins nearby. Road damage from the heavy truck traffic that fracking requires, with each well pad generating thousands of truck trips, falls on local governments and taxpayers.
Where Fracking Has Been Banned
Vermont became the first U.S. state to ban fracking in 2012, followed by New York in 2015, Maryland in 2017, Washington in 2019, and California in 2024. Oregon established a moratorium in 2019. Internationally, France, Germany, and Scotland have taken federal-level action to restrict or prohibit the practice. The pattern in each case has been similar: local communities raised concerns about water, health, and earthquakes, and legislators concluded the risks outweighed the economic benefits. In states without bans, regulation varies widely, and critics argue that state-level oversight has consistently failed to prevent the harms documented by researchers.