Reverse Osmosis System for Nitrates — Davidsonville, MD
A Davidsonville homeowner with a new baby had their well water tested and found nitrates at 9.8 mg/L — just below the EPA action level of 10 mg/L but a serious concern for infant health. We installed a 5-stage reverse osmosis system at the kitchen sink for drinking and cooking water.
The Problem
A Davidsonville homeowner called us after receiving their well water test results. They had tested the water before bringing their newborn home from the hospital — a precaution their pediatrician had recommended. The test showed nitrates at 9.8 mg/L, just below the EPA maximum contaminant level of 10 mg/L. The pediatrician had advised them not to use the tap water for formula or drinking until the nitrates were addressed. Nitrates at elevated levels cause methemoglobinemia ("blue baby syndrome") in infants under 6 months — a potentially fatal condition. The homeowner needed a solution immediately.
Our Diagnosis
We reviewed the test results and discussed the options. The nitrate level of 9.8 mg/L was below the EPA action level but above the level considered safe for infants. The source of the nitrates was most likely agricultural runoff — Davidsonville has significant agricultural land use, and nitrates from fertilizer leach into shallow wells. The long-term solution is a whole-home nitrate removal system (ion exchange), but the homeowner needed immediate protection for their infant. A point-of-use reverse osmosis system at the kitchen sink provides immediate, highly effective nitrate removal (95%+) for drinking and cooking water at a fraction of the cost of a whole-home system.
The Repair Process
- 1Reviewed water test results: nitrates 9.8 mg/L, pH 6.8, hardness 12 GPG, iron 0.8 ppm
- 2Discussed options: point-of-use RO vs. whole-home nitrate removal — homeowner chose POU RO for immediate protection
- 3Installed APEC ROES-50 5-stage reverse osmosis system under kitchen sink
- 4Stages: sediment pre-filter, carbon block pre-filter, RO membrane (50 GPD), carbon post-filter, inline carbon polishing filter
- 5Installed dedicated RO faucet at kitchen sink — separate from main tap
- 6Installed 3.2-gallon storage tank — provides immediate flow without waiting for membrane filtration
- 7Tested RO output for nitrates: 0.4 mg/L — 96% reduction from source water
- 8Provided homeowner with test results documentation for pediatrician
The Outcome
The RO system produces water with 0.4 mg/L nitrates — well below the EPA limit and safe for infant formula. The homeowner's pediatrician confirmed the RO water was safe for the baby. The system produces approximately 50 gallons per day — more than sufficient for drinking and cooking. The homeowner is now considering a whole-home nitrate removal system for the longer term, but the point-of-use RO provides immediate, documented protection for their infant.
Key Takeaway
Nitrates in well water are a serious concern for infants under 6 months. A point-of-use reverse osmosis system provides immediate, highly effective nitrate removal for drinking and cooking water. Always test well water before bringing a newborn home.
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