City of Rockville

Valued Rockville Residents, We're pleased to share this annual water quality report following another successful year where Rockville's water met or exceeded all regulatory standards. This report provides essential information about your water's source, treatment process, distribution system, and overall quality.

The City of Rockville provides water and sewer services to approximately 70% of the city, serving around 13,000 accounts and 52,000 residents. The Washington Suburban Sanitary Commission handles the remaining service area.

In the past year, we completed a $3 million renovation project on two critical water storage facilities: the 51-year-old Hunting Hill tank near Lakewood Country Club and the 55-year-old Carr Avenue tank near Beall Elementary School. These tanks together hold 11 million gallons of water. Improvements included essential safety upgrades, replacement of steel roof supports, comprehensive interior and exterior repainting, installation of a mixing system in the Carr Avenue tank to enhance water quality, and addition of wireless communications infrastructure to the Hunting Hill tank. These enhancements will significantly extend the tanks' lifespans, creating long-term cost benefits for our community.

The Mayor and Council have adopted a three-year water rate plan in the FY2019 budget to address our aging infrastructure needs. This necessary adjustment will fund ongoing repairs and replacements of aging water mains and other critical systems.

Our water treatment facility, which began operation 60 years ago, is currently undergoing a $5 million Electrical Distribution Systems Upgrade. This project will replace original electrical equipment that has served well beyond its expected lifespan with modern, high-efficiency systems to improve reliability in producing and delivering quality water. Design work is underway with construction expected to begin in 2020.

We invite you to learn more about Rockville's water system at www.RockvilleMD.gov/water and thank you for your continued support of our mission to maintain system integrity and deliver safe, high-quality water to all customers.

Is my water safe?

City of Rockville's municipal water meets all safety standards established by EPA regulations and enforced by the Maryland Department of the Environment (MDE). For calendar year 2017, our water met or exceeded all water quality requirements. The Water Quality Information Table on page 2 of this report lists all detected contaminants, none of which exceeded established standards.

Why are contaminants found in municipal water?

All water sources, including bottled water, may reasonably contain small amounts of some contaminants. Their presence doesn't necessarily indicate a health risk. For more information about contaminants and potential health effects, call the EPA Safe Drinking Water hotline at 1-800-426-4791.

Water sources (both tap and bottled) include rivers, lakes, streams, ponds, reservoirs, springs and wells. As water travels over land or underground, it dissolves naturally occurring minerals and can pick up substances from animal or human activities, including:

• Inorganic contaminants like salts and metals (naturally occurring or from urban runoff, wastewater discharges, oil/gas production, mining, or farming)
• Radioactive contaminants (naturally occurring or from energy production and mining)
• Microbial contaminants such as viruses and bacteria (from wastewater facilities, septic systems, agricultural operations, and wildlife)
• Fertilizers and pesticides (from agriculture, urban runoff, and residential uses)
• Organic chemical contaminants including synthetic and volatile compounds (from industrial processes, petroleum production, gas stations, stormwater runoff, and septic systems)

EPA regulations limit contaminant levels in public water supplies to ensure safe drinking water. FDA regulations establish similar limits for bottled water to provide equivalent public health protection.

Source water assessment

The Maryland Department of the Environment conducted a source water assessment of the Potomac River as it relates to Rockville's water plant. This 2002 report is available at www.mde.state.md.us/programs/water/water_supply/source_water_assessment_program or by calling MDE at 410-537-3589.

Rockville's Water Treatment Plant, in operation since 1958, initially produced 4 million gallons per day (MGD). Capacity increased to 8 MGD after a 1967 expansion. Additional upgrades in the mid-1990s and 2017 ensured compliance with EPA and MDE regulations. Today, approximately 5 million gallons of raw water is drawn daily from the Potomac River, treated through our six-step process, and distributed to customers.

Our six-step treatment process:

1. Screen: River water passes through screens to remove large debris like sticks and leaves. Potassium permanganate treats algae when present.
2. Coagulation: Chemical additives cause small suspended particles to clump together for easier removal.
3. Sedimentation: Water flows through settling basins where dirt, sand, metals and sediment settle out.
4. Filtration: Remaining contaminants are removed as water passes through dual media (sand and anthracite) filters.
5. Disinfection: Chlorine eliminates harmful pathogens. Fluoride is added for dental health and corrosion inhibitors protect distribution pipes.
6. Distribution: Treated water is stored in two tanks and gravity-fed to homes and businesses as needed.

Water quality is continuously monitored at the plant, throughout the distribution system, and at customer taps for lead, copper, potential contaminants, bacteria, and chlorine levels.

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