Are the data from the Water Quality Portal
(WQP) available through web services?
The WQP provides an easy way to access data stored in
various large water quality databases through form-based
queries as well as through standalone web services (A web
service is a computer-to-computer protocol that allows for
the direct sharing of information. Applications such as
internet portals can use the web services to access data
from the various databases without needing an authorized
database connection). The WQP provides various input
parameters on the form interface including location, site,
result, and date parameters to filter and customize the
output result set. Equivalent data retrievals can be
performed using web services, which have the same input
parameters and predefined output formats offered through
the form. For more information see the
How often are the data refreshed?
The USGS services are refreshed every 24 hours. The
STORET services are refreshed once a week on Thursday
How much data are available?
As of November 2011, nearly 200 million results from
over 2 million monitoring locations are currently
accessible through the portal. The portal reports samples
and results collected from each location since the
beginning of the databases.
Why do I have to add "USGS-" in front of my
NWIS site id when searching?
Why do I have to add the Organization ID in front of my
STORET site id when searching?
The site ids in the STORET and NWIS systems have not
been harmonized (unlike the case with characteristics).
Therefore, a site id may be duplicated across the two
systems. Furthermore, the site id within STORET is unable
to serve as a unique identifier for a site because STORET
aggregates data from different organizations who have not
harmonized their identifiers. Because of these reasons, the
WQP has chosen to prefix the simple site id in order to
make it a suitable unique identifier.
Why is the MonitoringLocationIdentifier not
quite the same as the site ID?
The MonitoringLocationIdentifier is meant to be
consistent within the WQP in the sense that any
MonitoringLocationIdentifier you get back from the WQP can
be re-input into the WQP as a site id search identifier.
However, if you are used to using STORET or NWIS, this site
id will not be consistent with the site id used by STORET
or NWIS. For the reasons why the WQP site id is different
from the STORET or NWIS site id, please see the answer to
the question above.
Why will Google Earth display a lot more points
than Google Maps when I download data in KML
KML files specify a set of sites that can be displayed
in Google Earth, Google Maps, or any other 3D Earth browser
compatible with KML. However, Google Maps currently has
specific limitations to the size and complexity of loaded
KML files. Google Maps can only support a maximum of 1,000
sites, whereas Google Earth can support much more. (Note:
this limit is temporary and is subject to change at any
Why do some queries take longer than others?
How can I reduce the time it takes for the WQP to
return my dataset?
Some queries take longer to return the resulting dataset
than other queries for various reasons. Large datasets will
take longer to return depending on file size and internet
connection speed. Mark the checkbox to compress your
dataset to speed up download time. Using certain filters
also affects query run time. Use the start date filters to
reduce the size of the resulting dataset and to reduce
query run time.