The city is not a State, so that clause would not apply to it. Unless you want to argue that the State of Mississippi was violating the Fourteenth Amendment by not requiring its cities to provide clean water (the article mentions that a few other states have done this). But this suit wasn't against the state.
This is tortured logic that would argue the Fourth Amendment doesn't apply to most police departments in the country and that town school boards could violate the First Amendment and have religious instruction.
States are co-sovereigns with the Feds. Your city is not. Your city's state cannot allow the local jurisdictions under it violate the Constitution either. Your town can't forbid black people from voting for mayor. etc. etc. etc.
> Held: Local units with general governmental powers over an entire geographic area may not, consistently with the Equal Protection Clause of the Fourteenth Amendment, be apportioned among single member districts of substantially unequal population.
> The Equal Protection Clause reaches the exercise of state power, whether exercised by the State or a political subdivision.
