Lower case states
The following query:
data=readNWISdata(stateCd="NY",
parameterCd="00600",service="measurements",
startDate="2016-01-01",endDate="2016-12-31")
Brings back all data...not just NY. Playing around with the surface water services, it looks like they only use lower-case state abbreviations.
We should double check all the services. If the waterservices allow lower case, we could just change all to lower case. If it's a matter of waterservics vs waterdata...we'll have to bake in that logic.