SCUA Upper Seven Mile
San Carlos, AZ · 8,478 people served · EPA PWSID 090400114
SCUA Upper Seven Mile (San Carlos, AZ), which serves about 8,478 people, has recorded 2 health-based drinking-water contaminants in EPA violation records since 2016, most notably Arsenic, Total Coliform / E. coli. Its most recent lead 90th-percentile sample was 5.0 ppb, within the 15 ppb federal action level. EPA's UCMR5 program detected PFAS 'forever chemicals' in this system: PFBS (0.0538 µg/L). 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
1.8× the federal limitKnown human carcinogen (skin, bladder, lung); also cardiovascular and developmental effects. Mostly naturally occurring in groundwater.
Lead
Within federal limitNo 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.
PFAS "forever chemicals"
Detected by EPA's UCMR5 monitoring. The 2024 federal limit for PFOA and PFOS is 4 ppt (0.004 µg/L).
PFBS
DetectedAlso on record
Total Coliform / E. coli
1 violationRecorded as a federal action-level / treatment violation (1 since 2016).
Indicator bacteria signalling fecal contamination pathway. Regulated by the Revised Total Coliform Rule.
Filters certified to clean up your water
Your water shows Arsenic, Lead, PFOA, PFOS, and 1 more. An under-sink filter handles the most of this in one unit — these three are independently certified for the most of your contaminants (not marketing claims):
Your water also has Arsenic — only reverse osmosis reliably removes these dissolved contaminants. See the best RO systems →
Note: bacteria (Total Coliform / E. coli) call for your utility's boil-water guidance or UV disinfection, not a filter.
Compare all certified under-sink 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.