dataretrieval 1.1.5

Discover and retrieve water data from U.S. federal hydrologic web services.

dataretrieval: Download hydrologic data

What is dataretrieval?

dataretrieval simplifies the process of loading hydrologic data into Python. Like the original R version dataRetrieval, it retrieves major U.S. Geological Survey (USGS) hydrology data types available on the Web, as well as data from the Water Quality Portal (WQP) and Network Linked Data Index (NLDI).

Check the NEWS for all updates and announcements.

Installation

Install dataretrieval using pip:

pip install dataretrieval

Or conda:

conda install -c conda-forge dataretrieval

Or directly from GitHub:

pip install git+https://github.com/DOI-USGS/dataretrieval-python.git

Usage Examples

Water Data API (Recommended - Modern USGS Data)

Access USGS water-monitoring data.

Important: Users are strongly encouraged to obtain an API key for higher rate limits. Register for an API key and set it as an environment variable:

import os
os.environ["API_USGS_PAT"] = "your_api_key_here"

The following example retrieves daily streamflow data for a specific monitoring location. The / in the time argument separates the start and end of the desired range:

from dataretrieval import waterdata

# Get daily streamflow data (returns DataFrame and metadata)
df, metadata = waterdata.get_daily(
    monitoring_location_id='USGS-01646500', 
    parameter_code='00060',  # Discharge
    time='2024-10-01/2025-09-30'
)

print(f"Retrieved {len(df)} records")
print(f"Site: {df['monitoring_location_id'].iloc[0]}")
print(f"Mean discharge: {df['value'].mean():.2f} {df['unit_of_measure'].iloc[0]}")

Retrieve streamflow at multiple locations from October 1, 2024 to the present:

df, metadata = waterdata.get_daily(
    monitoring_location_id=["USGS-13018750","USGS-13013650"],
    parameter_code='00060',
    time='2024-10-01/..'
)

print(f"Retrieved {len(df)} records")

Retrieve location information for all monitoring locations categorized as stream sites in Maryland:

# Get monitoring location information
df, metadata = waterdata.get_monitoring_locations(
    state_name='Maryland',
    site_type_code='ST'  # Stream sites
)

print(f"Found {len(df)} stream monitoring locations in Maryland")

Finally, retrieve continuous (a.k.a. "instantaneous") data for one location. We strongly advise breaking continuous data requests into smaller time windows to avoid timeouts and other issues:

# Get continuous data for a single monitoring location and water year
df, metadata = waterdata.get_continuous(
    monitoring_location_id='USGS-01646500', 
    parameter_code='00065',  # Gage height
    time='2024-10-01/2025-09-30'
)
print(f"Retrieved {len(df)} continuous gage height measurements")

Visit the API Reference for more information and examples on available services and input parameters.

For verbose troubleshooting and support — including the request URL sent to the API — enable debug-level logging:

import logging
logging.basicConfig(level=logging.DEBUG)

Water Quality Portal (WQP)

Access water quality data from multiple agencies:

from dataretrieval import wqp

# Find water quality monitoring sites
sites = wqp.what_sites(
    statecode='US:55',  # Wisconsin
    siteType='Stream'
)

print(f"Found {len(sites)} stream monitoring sites in Wisconsin")

# Get water quality results
results = wqp.get_results(
    siteid='USGS-05427718',
    characteristicName='Temperature, water'
)

print(f"Retrieved {len(results)} temperature measurements")

Network Linked Data Index (NLDI)

Discover and navigate hydrologic networks:

from dataretrieval import nldi

# Get watershed basin for a stream reach
basin = nldi.get_basin(
    feature_source='comid',
    feature_id='13293474'  # NHD reach identifier  
)

print(f"Basin contains {len(basin)} feature(s)")

# Find upstream flowlines
flowlines = nldi.get_flowlines(
    feature_source='comid',
    feature_id='13293474',
    navigation_mode='UT',  # Upstream tributaries
    distance=50  # km
)

print(f"Found {len(flowlines)} upstream tributaries within 50km")

Available Data Services

Modern USGS Water Data APIs (Recommended)

• Daily values: Daily statistical summaries (mean, min, max)
• Instantaneous values: High-frequency continuous data
• Field measurements: Discrete measurements from field visits
• Monitoring locations: Site information and metadata
• Time series metadata: Information about available data parameters
• Latest daily values: Most recent daily statistical summary data
• Latest instantaneous values: Most recent high-frequency continuous data
• Daily, monthly, and annual statistics: Median, maximum, minimum, arithmetic mean, and percentile statistics
• Samples data: Discrete USGS water quality data

Legacy NWIS Services (Deprecated)

• Daily values (dv): Legacy daily statistical data
• Instantaneous values (iv): Legacy continuous data
• Site info (site): Basic site information
• Statistics (stat): Statistical summaries
• Discharge peaks (peaks): Annual peak discharge events

Water Quality Portal

• Results: Water quality analytical results from USGS, EPA, and other agencies
• Sites: Monitoring location information
• Organizations: Data provider information
• Projects: Sampling project details

Network Linked Data Index (NLDI)

• Basin delineation: Watershed boundaries for any point
• Flow navigation: Upstream/downstream network traversal
• Feature discovery: Find monitoring sites, dams, and other features
• Hydrologic connectivity: Link data across the stream network

More Examples

Explore additional examples in the demos directory, including Jupyter notebooks demonstrating advanced usage patterns.

Getting Help

• Issue tracker: Report bugs and request features at https://github.com/DOI-USGS/dataretrieval-python/issues
• Documentation: https://doi-usgs.github.io/dataretrieval-python/

Contributing

Contributions are welcome! Please see CONTRIBUTING.md for development guidelines.

Acknowledgments

This material is partially based upon work supported by the National Science Foundation (NSF) under award 1931297. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the NSF.

Disclaimer

This software is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The software has not received final approval by the U.S. Geological Survey (USGS). No warranty, expressed or implied, is made by the USGS or the U.S. Government as to the functionality of the software and related material nor shall the fact of release constitute any such warranty. The software is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the software.

Citation

Hodson, T.O., Hariharan, J.A., Black, S., and Horsburgh, J.S., 2023, dataretrieval (Python): a Python package for discovering and retrieving water data available from U.S. federal hydrologic web services: U.S. Geological Survey software release, https://doi.org/10.5066/P94I5TX3.