Nashville is one of the fastest-growing cities in America — a boom that’s testing every piece of infrastructure the city has, including its water system.
Metro Water Services (MWS), Nashville’s water and sewer utility, serves approximately 700,000 people in Davidson County. The utility draws from the Cumberland River, treating water at the Omohundro Water Treatment Plant (one of the largest conventional treatment plants in the Southeast) and the K.R. Harrington Water Treatment Plant.
The Cumberland River is a major tributary of the Ohio River, draining about 18,000 square miles across Tennessee and Kentucky. By the time it reaches Nashville, it’s collected agricultural runoff, treated wastewater from upstream communities, and whatever else enters the watershed.
Lead: An Aging City’s Hidden Problem
Nashville experienced its major residential building boom from the 1890s through the 1960s — decades when lead service lines and lead solder were standard construction materials. Neighborhoods like East Nashville, Germantown, The Nations, Sylvan Park, and North Nashville have significant concentrations of older homes with potential lead plumbing.
MWS has estimated that tens of thousands of lead service lines may remain in the distribution system, though the utility has been building a comprehensive inventory as required under EPA’s LCRI.
Nashville’s water is treated with corrosion inhibitors (orthophosphate) to minimize lead leaching from pipes and plumbing. The system’s lead testing results have generally remained below EPA’s action level of 15 parts per billion at the 90th percentile.
But Nashville’s rapid growth has created a complication: as older neighborhoods gentrify and homes are renovated, construction work can physically disturb lead service lines, potentially releasing lead particles into the water. The intersection of rapid development and aging lead infrastructure creates risks that standard corrosion control doesn’t fully address.
PFAS: Emerging Data
Tennessee has been slower than some states to address PFAS contamination, but the data is becoming harder to ignore.
Key PFAS concerns in the Nashville area:
- Military installations — Fort Campbell, straddling the Tennessee-Kentucky border about 65 miles northwest of Nashville, has documented PFAS contamination from AFFF use. While Fort Campbell’s contamination primarily affects Clarksville and surrounding communities, it highlights the broader military PFAS problem in Tennessee.
- Nashville International Airport (BNA) — Like all major airports, BNA has used AFFF. Preliminary sampling has detected PFAS in the vicinity.
- Industrial sources — Nashville’s industrial sector includes manufacturing operations that may have used PFAS compounds, though comprehensive site-by-site data is still developing.
- UCMR 5 results — Testing under EPA’s Fifth Unregulated Contaminant Monitoring Rule has detected PFAS in Tennessee water systems, including in the Nashville area, though specific levels vary by sample location and date.
Tennessee’s Department of Environment and Conservation (TDEC) has been working on a statewide PFAS assessment, but the state has not yet established state-level PFAS drinking water standards beyond the federal MCLs.
Cumberland River Source Water
Nashville’s raw water quality reflects the upstream watershed:
- Agricultural runoff — The Cumberland River basin includes significant farmland in Tennessee and Kentucky. Nutrient loading (nitrogen and phosphorus) from fertilizer and animal operations affects source water quality.
- Treated wastewater — Multiple upstream communities discharge treated wastewater into the Cumberland. While permitted and monitored, these discharges introduce pharmaceuticals, nutrients, and trace chemicals.
- Stormwater and urban runoff — As Nashville grows, more impervious surfaces (roads, parking lots, rooftops) increase stormwater runoff volume and contaminant loading.
- Coal ash — Tennessee has coal-fired power plants that produce coal ash, which can contaminate surface water and groundwater with heavy metals. The 2008 Kingston Fossil Plant coal ash spill in eastern Tennessee — one of the largest environmental disasters in US history — demonstrated the risk.
MWS treats Cumberland River water with conventional processes: coagulation, sedimentation, filtration, and chloramine disinfection. The treatment is effective, but source water quality determines how hard the treatment plant has to work.
Infrastructure Under Pressure
Nashville’s growth has outpaced infrastructure investment in several areas:
- Sewer overflows — MWS operates a combined sewer system in older parts of the city and separate systems in newer areas. During heavy rain, sanitary sewer overflows (SSOs) release untreated or partially treated sewage into the Cumberland and its tributaries. Nashville has been operating under a consent decree with EPA to reduce SSOs through system upgrades.
- Water main breaks — Aging water mains in older neighborhoods are prone to breaks, causing service disruptions and boil water advisories.
- Capacity constraints — Treatment plants and distribution systems designed for a smaller population are being stressed by rapid growth in areas like southeast Nashville, Antioch, and other suburban growth corridors.
The cost of catching up is enormous. MWS has proposed billions in capital improvements over the next decade, funded through rate increases that have been controversial with ratepayers.
What Nashville Residents Should Know
- Your water is treated and tested. MWS meets all federal drinking water standards. Read the annual water quality report for specific testing data.
- Check for lead. If your home was built before 1986 — common in Nashville’s older neighborhoods — you may have lead solder or service lines. Contact MWS for a service line check.
- Flush before drinking. Run cold water for 30 seconds to 2 minutes if it’s been sitting in pipes for hours. Especially important in older homes.
- Use a filter. A point-of-use filter certified to NSF/ANSI 53 removes lead. Carbon filters address chloramine taste and DBPs.
- Report issues. Discolored water, low pressure, or unusual taste or odor should be reported to MWS. These can indicate system problems that need attention.
- Private well owners in Davidson County and surrounding areas should test annually for bacteria, nitrates, and other contaminants.
The Bottom Line
Nashville’s water system is adequate but under growing strain. The combination of rapid population growth, aging infrastructure, lead service lines in older neighborhoods, and emerging PFAS concerns creates a set of challenges that will require sustained investment over the coming decades.
The city’s consent decree obligations for sewer upgrades are already expensive, and the LCRI lead service line replacement mandate will add significantly to the bill. How Nashville funds these improvements while maintaining affordability for lower-income residents is a defining infrastructure question for the city.
If you’re concerned about your water quality, a certified water treatment professional can test your water and recommend solutions appropriate for your home.