USGS Surface Water for USA: Peak Streamflow

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Peak Streamflow for the Nation

USGS 08171350 Blanco Rv at San Marcos, TX

Hays County, Texas

Hydrologic Unit Code 12100203

Latitude 29°52'46.24", Longitude 97°54'38.71" NAD83

Drainage area 436.0 square miles

Gage datum 542.97 feet above NAVD88

Water Year	Date	Gage Height (feet)	Stream- flow (cfs)
2016	2015-10-30	42.45	171,000²
2017	2017-04-12	13.49	2,660²
2018	2018-09-09	13.99	2,780
2019	2019-05-09	24.14	19,800²
2020	2020-05-25	15.26	3,350
2021	2021-06-05	10.40	689
2022	2021-10-14	24.66	15,500
2023	2023-04-21	9.32	146
2024	2023-10-26	11.56	884

Peak Streamflow Qualification Codes.

U.S. Department of the Interior | U.S. Geological Survey
Title: Surface Water for USA: Peak Streamflow
URL: https://nwis.waterdata.usgs.gov/nwis/peak?

Page Contact Information: USGS Water Data Support Team
Page Last Modified: 2025-07-07 00:53:13 EDT
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