The monitoring network within this area

Hydrionis holds 1,160 values from 4 gauges within it. Discharge is a property of a gauge and its reach, not of this drainage area, so this page reports the network and its records rather than a single figure.

Gauges

1,160

Values held

1925–2026

Record spans

Gauges within the South Fork Shenandoah huc8 subbasin

4 monitoring points, positioned as the publisher records them.

Flood peaks, as measured

This gauge's flood record, as measured. Unlike a daily mean it is the discharge at the moment the river was highest, which is the figure flood frequency analysis is built on.

Largest measured flow of each year at MIDDLE RIVER NEAR GROTTOES, VA

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1928–2025.

Show relevant events (1 event)Shading marks when something was recorded, not what caused the line.

Published by the gauge's own operator from its sub-daily record; Hydrionis stores the figure rather than recomputing it. A year the gauge did not cover produces no value rather than a low one, and the gaps are stated below the chart. A peak is a property of this gauge and its reach: a larger flood upstream or downstream of it is not in this series.

What the shaded periods are (1 event)

A shaded period marks when something was recorded, not what caused the shape of the line. Where the two coincide, they coincided.

Documented record — A documented event, compiled from cited sources after it happened. The dates are as good as the record, which for older events can mean the month rather than the day.

Event	Type	Period	Standing	Authority
Hurricane Katrina water and sanitation collapse	Flood	2005-08-29 – 2005-09-30	Documented record	Compiled record

Not shown on this chart

The 1976 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
The 2022 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Yorkshire drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Cantareira water crisis, São Paulo — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Cape Town Day Zero — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
European drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.

View the data behind this chart

Underlying data
Period	MIDDLE RIVER NEAR GROTTOES, VA (m³/s)
1928	163
1929	172
1931	71.6
1932	119
1934	119
1936	694
1937	274
1939	150
1940	354
1941	59.2
1942	334
1944	193
1945	379
1947	108
1948	254
1949	456
1950	79.6
1952	131
1953	183
1954	140
1955	360
1956	39.6
1957	133
1958	119
1959	91.5
1960	158
1961	87.5
1963	203
1964	79.3
1965	91.5
1966	65.7
1967	222
1969	166
1971	317
1972	462
1973	243
1975	340
1976	144
1978	283
1979	217
1981	20.0
1982	196
1983	187
1984	202
1985	74.5
1987	345
1988	42.8
1989	130
1990	136
1992	320
1993	377
1994	157
1995	155
1996	1,254
1998	272
1999	38.2
2000	51.5
2001	144
2002	41.9
2003	365
2004	272
2005	56.6
2006	172
2008	71.1
2009	73.3
2010	300
2011	253
2013	221
2014	119
2015	127
2016	122
2017	168
2018	314
2020	153
2022	84.4
2023	78.4
2024	277
2025	155

About this series

Everything below is a property of the data rather than a rating of it. There is deliberately no single confidence score: how much a gap matters depends on what you are about to do with the series, and only you know that.

Source	United States Geological Survey — National Water Information System · US Government work — public domain
How the values came to exist	Measured
Period held	1928–2025
Completeness	79.6% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	20 separate periods inside 1928–2025 hold no value. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1928 and is not continuous from it: 98 years separate the first value from the last, and 80% of the years between them are held. The span is not the record.
Last read from the publisher	2026-10-01
Redistribution	Permitted by the upstream licences
Commercial reuse	Permitted by the upstream licences. No Hydrionis access tier can widen this.
Methodology	How this was produced

How much of the rain came back out

A discharge in cubic metres per second cannot be compared with anything: the larger number may only mean the larger catchment. Divided by the area draining to the gauge it becomes a depth of water over that land, which answers a question a reader already has — of the rain that fell here, how much came back out as river?

Water leaving the catchment above MIDDLE RIVER NEAR GROTTOES, VA, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1928–2024.

Show relevant events (1 event)Shading marks when something was recorded, not what caused the line.

Computed by Hydrionis from the published annual mean flow and the catchment area the station's own publisher states. It is not a water balance: the difference between rainfall and runoff is not evaporation alone but also change in groundwater storage, water abstracted and taken elsewhere, and water imported by transfer schemes — which is why a catchment can yield more runoff than the rain that fell on it without anything being measured wrongly. A different area figure rescales every value here by the ratio between them.

What the shaded periods are (1 event)

A shaded period marks when something was recorded, not what caused the shape of the line. Where the two coincide, they coincided.

Documented record — A documented event, compiled from cited sources after it happened. The dates are as good as the record, which for older events can mean the month rather than the day.

Event	Type	Period	Standing	Authority
Hurricane Katrina water and sanitation collapse	Flood	2005-08-29 – 2005-09-30	Documented record	Compiled record

Not shown on this chart

The 1976 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
The 2022 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Yorkshire drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Cantareira water crisis, São Paulo — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Cape Town Day Zero — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
European drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.

View the data behind this chart

Underlying data
Period	MIDDLE RIVER NEAR GROTTOES, VA (mm)
1928	297
1929	300
1930	120
1931	154
1932	258
1933	287
1934	209
1935	426
1936	483
1937	479
1938	179
1939	225
1940	327
1941	169
1942	334
1943	291
1944	241
1945	252
1946	228
1947	192
1948	429
1949	461
1950	277
1951	304
1952	354
1953	241
1954	230
1955	298
1956	145
1957	240
1958	332
1959	209
1960	318
1961	277
1962	321
1963	236
1964	211
1965	200
1966	197
1967	259
1968	194
1969	179
1970	232
1971	364
1972	548
1973	420
1974	262
1975	374
1976	279
1977	176
1978	336
1979	506
1980	312
1981	103
1982	325
1983	377
1984	408
1985	388
1986	202
1987	403
1988	146
1989	381
1990	346
1991	311
1992	287
1993	363
1994	383
1995	249
1996	598
1997	284
1998	558
1999	162
2000	178
2001	152
2002	112
2003	633
2004	330
2005	244
2006	316
2007	277
2008	158
2009	244
2010	318
2011	315
2012	236
2013	330
2014	318
2015	321
2016	309
2017	227
2018	581
2019	418
2020	434
2021	307
2022	232
2023	166
2024	266

About this series

Source	United States Geological Survey — National Water Information System · US Government work — public domain
How the values came to exist	Derived Computed by Hydrionis
Period held	1928–2024
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1928 to 2024 is held.
Inputs last read	2026-10-01 · when the records this was computed from were last read from their publishers
Calculation date	2026-08-24 · when the calculation method was last versioned, not a reading of any publisher
Redistribution	Permitted by the upstream licences
Commercial reuse	Permitted by the upstream licences. No Hydrionis access tier can widen this.
Methodology	How this was produced

Every gauge Hydrionis holds within this area

Gauges within the South Fork Shenandoah and what each holds
Gauge	Measures	Values	Record
MIDDLE RIVER NEAR GROTTOES, VA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	330	1927–2026
NORTH RIVER NEAR BURKETOWN, VA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	321	1926–2026
SOUTH RIVER AT HARRISTON, VA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	283	1925–2026
S F SHENANDOAH RIVER NEAR LURAY, VA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	226	1925–2026

How these gauges were attached to this water

Assigned by the publisher to a numbered basin Every gauge here is assigned to this drainage area by its own publisher, which issues the area an official code — 02070005. A drainage area is not a river: it contains the tributaries as well as the main channel, and a gauge in it may be on any of them.

What each gauge’s link to this water rests on
Gauge	Evidence	Established
MIDDLE RIVER NEAR GROTTOES, VA	Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4	2026-10-02
NORTH RIVER NEAR BURKETOWN, VA	Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4	2026-10-02
SOUTH RIVER AT HARRISTON, VA	Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4	2026-10-02
S F SHENANDOAH RIVER NEAR LURAY, VA	Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4	2026-10-02

What this record holds

Hydrionis decides which waters get a page, and which of those are offered to search, from what is actually held rather than from how the page reads. Five signals are counted; this record has 5 of them, which makes it a full profile.

Information-gain signals held for this water body
Signal	Held	Counts
Gauges holding a real record	4	yes, 3 or more
Years spanned	102	yes, 20 or more
Values held	1,160	yes, 1000 or more
Distinct measurements	5	yes, 2 or more
Publishers measuring it	2	yes, 2 or more
Official identifiers	1	recorded, not counted

Use this data

Machine-readable JSON /api/v1/observations/by-subject/gauge-usgs-01625000.json
How to cite this, and who you must credit
How these figures were produced
Request this at a different scale, format or geography

No bulk download is offered here, which is a licence position rather than a product one: at least one contributing publisher does not permit redistribution. The values can be read on the page, cited, and pointed to at source.

Attribution and citation

Suggested citation for Hydrionis

Hydrionis (2026), South Fork Shenandoah gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-south-fork-shenandoah/

Cite Hydrionis where you rely on values Hydrionis computed, on the method that produced them, or on the compilation itself. The underlying measurements remain the publishers’ and their attribution requirements apply to you directly.

Recommended, not required. Hydrionis does not claim rights over unmodified public data it relayed, and doing arithmetic on somebody else’s measurements does not make them Hydrionis’s. Cite the version and the access date: the South Fork Shenandoah gauge records changes as publishers release and as methods are revised, and a citation without both cannot be checked later. Full guidance is on cite and reuse.

None of the contributing licences requires attribution. Crediting the publishers is still good practice and they are listed above.

Where these figures come from

MeasuredHigh confidence2025-07-02

Source: USGS — National Water Information System, USGS site 01625000, annual peak streamflow. Licence: Open.

Method: The instantaneous maximum discharge of each water year as published by USGS, dated to the day it occurred. One value per October-to-September water year; where the publisher lists both a systematic and a historic peak for a year, the larger is the annual maximum. Values the publisher marks as maximum daily averages are not held here, because they are not instantaneous peaks. Values marked as bounded rather than measured are held as censored observations carrying the bound. Cubic feet per second are converted to cubic metres per second and the publisher unit is recorded alongside.

Rating curves are extrapolated at extreme discharges, so the largest values in a peak series carry the largest measurement uncertainty. Data from the U.S. Geological Survey National Water Information System, a work of the United States government and therefore in the public domain.

Retrieved 1 October 2026.