CSA 70 W-4 PIONEERTOWN
SAN BERNARDINO, CA · 470 people served · EPA PWSID CA3600196
CSA 70 W-4 PIONEERTOWN (SAN BERNARDINO, CA), which serves about 470 people, has recorded 2 health-based drinking-water contaminants in EPA violation records since 2016, most notably Arsenic, Fluoride. Its most recent lead 90th-percentile sample was 0.0 ppb, within the 15 ppb federal action level. A certified water filter can reduce these at the tap — see the certified options for each below.
What the testing found
Measured levels from EPA violation records, compared to the federal limit (MCL). The black line marks the legal limit.
Arsenic
7.6× the federal limitKnown human carcinogen (skin, bladder, lung); also cardiovascular and developmental effects. Mostly naturally occurring in groundwater.
Fluoride
2.1× the federal limitAdded for dental health at ~0.7 mg/L; EPA MCL 4 mg/L. Excess causes dental/skeletal fluorosis. Can be naturally high in some groundwater.
Lead
Not detectedNo safe level. Damages developing brain/nervous system in children; linked to lower IQ, kidney and cardiovascular harm in adults. Usually enters water from corroding pipes/solder, not the source.
Filters certified to clean up your water
Your water shows Arsenic, Fluoride. A reverse osmosis system handles the most of this in one unit — these three are independently certified for the most of your contaminants (not marketing claims):
Compare all certified reverse osmosis filters →
Want certainty about your tap specifically (not just the system)? A certified mail-in lab test is the gold standard — system-wide records can differ from your home's plumbing. Some links above are affiliate links — see our disclosure.
Sources & method. Contaminant levels and violations come from EPA's Safe Drinking Water Information System (health-based violations, 2016–present); PFAS from EPA UCMR5 monitoring (2023–2025). Levels shown are the highest recorded value in the violation records; a violation means the contaminant exceeded its federal limit at the system level. Your home's water can differ from the system average. Public domain data; we are not affiliated with the EPA.