Where Does Hyannis's Water Come From?
Water Source
Hyannis Water System groundwater wells (sole source aquifer)
Hyannis, the commercial hub of Cape Cod, relies entirely on groundwater pumped from the Cape Cod sole source aquifer. This aquifer is the only source of drinking water for Cape Cod — and it has been severely impacted by PFAS contamination from Joint Base Cape Cod (formerly Otis Air National Guard Base). The contamination plume extends for miles through the aquifer.
What's in Hyannis's Water?
Based on water quality reports, testing data, and environmental assessments, these are the contaminants of concern for Hyannis residents:
PFAS ("Forever Chemicals")
Status: CRITICAL — Joint Base Cape Cod plume
Joint Base Cape Cod used PFAS-containing AFFF firefighting foam for decades. The contamination plume has spread through the sole source aquifer, affecting multiple Hyannis water supply wells. Some wells have been shut down; others require specialized treatment.
PFOA (Perfluorooctanoic Acid)
Status: Exceeded new EPA limits
PFOA, one of the most studied and dangerous PFAS compounds, has been detected above the new EPA maximum contaminant level of 4 parts per trillion. Linked to kidney cancer, testicular cancer, and other serious health effects.
PFOS (Perfluorooctane Sulfonate)
Status: Exceeded new EPA limits
PFOS, used in AFFF firefighting foam, is the primary PFAS contaminant from military base operations. Detected at levels above the new 4 ppt EPA limit in multiple wells.
Nitrates
Status: Seasonal concerns
Cape Cod's sandy soils and reliance on septic systems contribute to nitrate loading in the groundwater. Seasonal tourism increases wastewater volume during summer months.
Health Risks for Hyannis Residents
According to the EPA and Environmental Working Group (EWG), prolonged exposure to contaminants found in Hyannis's water may increase risk of:
- • Cancer: PFOA is linked to kidney and testicular cancer. PFOS is linked to liver, thyroid, and breast cancer. Military families and nearby residents have elevated cancer rates.
- • Thyroid Disease: PFAS disrupt thyroid hormone production, affecting metabolism, growth, and development
- • Immune Suppression: PFAS reduce the body's immune response, including reduced vaccine effectiveness — documented in Cape Cod studies
- • Reproductive Harm: PFAS exposure is linked to reduced fertility, pregnancy complications, and developmental delays
📍 Hyannis Local Tip
Cape Cod residents have been fighting the PFAS contamination issue for years. The nonprofit Cape Cod Water Protection Collaborative tracks contamination data and treatment progress. If you're in Hyannis, your water utility has installed granular activated carbon treatment on affected wells — but an in-home RO system provides an additional layer of protection, especially during treatment system transitions.
The Solution: Reverse Osmosis Filtration
Standard pitcher filters (like Brita) are not effective at removing PFAS or most contaminants found in Hyannis's water. Water quality experts recommend a Reverse Osmosis (RO) system that can remove up to 99% of dissolved contaminants.
Why RO Works for Hyannis Water:
- ✓ Removes 99%+ of PFAS, PFOA, PFOS
- ✓ Uses semi-permeable membrane to filter at molecular level
- ✓ Fits under your kitchen sink — no major renovation needed
- ✓ Provides clean drinking and cooking water on demand
- ✓ NSF-certified systems are independently tested and verified
Top Recommended RO Systems for Hyannis
APEC ROES-50
A reliable, no-frills workhorse — perfect for Hyannis families on a budget.
- • 5-Stage filtration system
- • Removes up to 99% of contaminants including PFAS
- • Industry-standard parts (easy, affordable replacements)
- • Excellent long-term track record with thousands of reviews
iSpring RCC7AK
Best for taste — adds healthy minerals back after filtering Hyannis's water.
- • 6-Stage with alkaline remineralization
- • Water tastes like natural spring water
- • See-through housing shows filter condition
- • Top-rated by Hyannis area homeowners
Waterdrop G3P800
The modern, space-saving tankless choice for Hyannis homes.
- • Tankless design saves cabinet space
- • 800 GPD flow rate (fills a cup in seconds)
- • Smart faucet displays real-time water quality
- • Easy twist-and-pull filter changes — no plumber needed
Ready to Install?
Step-by-step DIY installation guide — works for any Hyannis home
View Installation Guide →Frequently Asked Questions — Hyannis Water
Is Hyannis water safe to drink?
Hyannis water has been significantly affected by PFAS contamination from Joint Base Cape Cod. While the water utility has installed treatment systems, many health experts recommend additional home filtration — particularly a reverse osmosis system — as PFAS levels can fluctuate and new compounds continue to be discovered.
How did Joint Base Cape Cod contaminate the water?
For decades, the military base used AFFF (aqueous film-forming foam) containing PFAS for firefighting training and emergency response. These chemicals leached into the sandy Cape Cod soil and entered the sole source aquifer that provides all of Cape Cod's drinking water.
What is being done about PFAS in Hyannis water?
The Hyannis Water System has installed granular activated carbon (GAC) treatment on affected wells. The military is also conducting cleanup efforts. However, the contamination plume is massive and PFAS are incredibly persistent — cleanup will take decades.
Do I need a water filter in Hyannis?
Yes, strongly recommended. Even with municipal treatment, a home reverse osmosis system provides a critical second barrier against PFAS. RO systems remove 95-99% of PFAS compounds, including ones that municipal GAC treatment may miss.
Sources
- • Hyannis Water System Annual Water Quality Report (2024)
- • EPA PFAS Strategic Roadmap — Joint Base Cape Cod
- • Massachusetts DEP PFAS Monitoring Results
- • Cape Cod Water Protection Collaborative
- • Agency for Toxic Substances and Disease Registry (ATSDR) — Cape Cod Studies