thats illegal if its tap water. they have to pump water thats 500ppm or less through municipal lines according to law. unless thats your well water.
I disagree. TDS is considered a secondary standard by the EPA, at 500 ppm. It is not enforceable. It is considered a cosmetic inconvenience. States may individually make law regarding water qualiy, but the EPA doesnt care if your municipal TDS is 1200 ppm. Because TDS doesnt tell us what the individual ppms are (could be arsenic, could be calcium), they dont enforce it.
And even if the municipality violates a primary drinking water standard, such as arsenic, cyanide, etc, the municipality can still serve the water to the public as long as they inform them what contaminants they have and what the risks are. They do this by sending a letter to every address they service saying "the EPA requires us to inform you that you have xyz contaminant at 123 ppms above the mcl. The known side effects are abc and you may want to consider an alternative source for your drinking water such as bottled water"
Here maybe this will help:
National Secondary Drinking Water Regulations
National Secondary Drinking Water Regulations (NSDWRs or secondary standards) are non-enforceable guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water. EPA recommends secondary standards to water systems but does not require systems to comply. However, states may choose to adopt them as enforceable standards.
List of National Secondary Drinking Water Regulations
Contaminant
Secondary Standard
Aluminum
0.05 to 0.2 mg/L
Chloride
250 mg/L
Color
15 (color units)
Copper
1.0 mg/L
Corrosivity
noncorrosive
Fluoride
2.0 mg/L
Foaming Agents
0.5 mg/L
Iron
0.3 mg/L
Manganese
0.05 mg/L
Odor
3 threshold odor number
pH
6.5-8.5
Silver
0.10 mg/L
Sulfate
250 mg/L
Total Dissolved Solids
500 mg/L
Zinc
5 mg/L