USGS dataretrieval Python Package get_discharge_measurements() Examples

This notebook provides examples of using the Python dataretrieval package to retrieve surface water discharge measurement data for a United States Geological Survey (USGS) monitoring site. The dataretrieval package provides a collection of functions to get data from the USGS National Water Information System (NWIS) and other online sources of hydrology and water quality data, including the United States Environmental Protection Agency (USEPA).

Install the Package

Use the following code to install the package if it doesn’t exist already within your Jupyter Python environment.

[1]:
!pip install dataretrieval
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Load the package so you can use it along with other packages used in this notebook.

[2]:
from IPython.display import display

from dataretrieval import nwis
import dataretrieval.waterdata as waterdata

Basic Usage

The dataretrieval package has several functions that allow you to retrieve data from different web services. This examples uses the get_discharge_measurements() function to retrieve surface water discharge measurements for a USGS monitoring site from NWIS. The function has the following arguments:

Arguments (Additional arguments, if supplied, will be used as query parameters)

  • sites (list of strings): A list of USGS site codes to retrieve data for. If the qwdata parameter site_no is supplied, it will overwrite the sites parameter.

  • start (string): The beginning date of a period for which to retrieve measurements. If the qwdata parameter begin_date is supplied, it will overwrite the start parameter.

  • end (string): The ending date of a period for which to retrieve measurements. If the qwdata parameter end_date is supplied, it will overwrite the end parameter.

Example 1: Get all of the surface water measurements for a single site

[3]:
measurements1 = waterdata.get_field_measurements(monitoring_location_id="10109000")
print("Retrieved " + str(len(measurements1[0])) + " data values.")
Retrieved 0 data values.

Interpreting the Result

The result of calling the get_discharge_measurements() function is an object that contains a Pandas data frame object and an associated metadata object. The Pandas data frame contains the discharge measurements for the time period requested.

Once you’ve got the data frame, there’s several useful things you can do to explore the data.

Display the data frame as a table

[4]:
display(measurements1[0])
geometry field_visit_id parameter_code monitoring_location_id observing_procedure_code observing_procedure value unit_of_measure time qualifier vertical_datum approval_status measuring_agency last_modified control_condition measurement_rated field_measurement_id

Show the data types of the columns in the resulting data frame.

[5]:
print(measurements1[0].dtypes)
geometry                           object
field_visit_id                     object
parameter_code                     object
monitoring_location_id             object
observing_procedure_code           object
observing_procedure                object
value                               int64
unit_of_measure                    object
time                        datetime64[s]
qualifier                          object
vertical_datum                     object
approval_status                    object
measuring_agency                   object
last_modified               datetime64[s]
control_condition                  object
measurement_rated                  object
field_measurement_id               object
dtype: object

The other part of the result returned from the get_discharge_measurements() function is a metadata object that contains information about the query that was executed to return the data. For example, you can access the URL that was assembled to retrieve the requested data from the USGS web service. The USGS web service responses contain a descriptive header that defines and can be helpful in interpreting the contents of the response.

[6]:
print("The query URL used to retrieve the data from NWIS was: " + measurements1[1].url)
The query URL used to retrieve the data from NWIS was: https://api.waterdata.usgs.gov/ogcapi/v0/collections/field-measurements/items?monitoring_location_id=10109000&skipGeometry=False&limit=50000

Additional Examples

Example 2: Get all of the surface water measurements between a start and end date

[7]:
measurements2 = waterdata.get_field_measurements(
    monitoring_location_id="10109000", time="2019-01-01/2019-12-31"
)
print("Retrieved " + str(len(measurements2[0])) + " data values.")
display(measurements2[0])
Retrieved 0 data values.
geometry field_visit_id parameter_code monitoring_location_id observing_procedure_code observing_procedure value unit_of_measure time qualifier vertical_datum approval_status measuring_agency last_modified control_condition measurement_rated field_measurement_id

Example 3: Get all of the surface water measurements for multiple sites

[8]:
measurements3 = waterdata.get_field_measurements(monitoring_location_id=["01594440", "040851325"])
print("Retrieved " + str(len(measurements3[0])) + " data values.")
display(measurements3[0])
Retrieved 0 data values.
geometry field_visit_id parameter_code monitoring_location_id observing_procedure_code observing_procedure value unit_of_measure time qualifier vertical_datum approval_status measuring_agency last_modified control_condition measurement_rated field_measurement_id