Land subsidence in the San Joaquin Valley, California, USA, 2007–2014
Rapid land subsidence was recently measured using multiple methods in two areas of the San Joaquin Valley (SJV): between Merced and Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent land-use changes and diminished surface-water availability have led to increased groundwater p...
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2015-11-01
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Online Access: | https://www.proc-iahs.net/372/23/2015/piahs-372-23-2015.pdf |
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doaj-74f259a8608f4f73ba87d6264e9f188f2020-11-24T23:16:28ZengCopernicus PublicationsProceedings of the International Association of Hydrological Sciences2199-89812199-899X2015-11-01372232710.5194/piahs-372-23-2015Land subsidence in the San Joaquin Valley, California, USA, 2007–2014M. Sneed0J. T. Brandt1US Geological Survey, 6000 J Street, Placer Hall, Sacramento, CA 95819, USAUS Geological Survey, 6000 J Street, Placer Hall, Sacramento, CA 95819, USARapid land subsidence was recently measured using multiple methods in two areas of the San Joaquin Valley (SJV): between Merced and Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent land-use changes and diminished surface-water availability have led to increased groundwater pumping, groundwater-level declines, and land subsidence. Differential land subsidence has reduced the flow capacity of water-conveyance systems in these areas, exacerbating flood hazards and affecting the delivery of irrigation water. <br><br> Vertical land-surface changes during 2007–2014 were determined by using Interferometric Synthetic Aperture Radar (InSAR), Continuous Global Positioning System (CGPS), and extensometer data. Results of the InSAR analysis indicate that about 7600 km<sup>2</sup> subsided 50–540 mm during 2008–2010; CGPS and extensometer data indicate that these rates continued or accelerated through December 2014. The maximum InSAR-measured rate of 270 mm yr<sup>−1</sup> occurred in the El Nido area, and is among the largest rates ever measured in the SJV. In the Pixley area, the maximum InSAR-measured rate during 2008–2010 was 90 mm yr<sup>−1</sup>. Groundwater was an important part of the water supply in both areas, and pumping increased when land use changed or when surface water was less available. This increased pumping caused groundwater-level declines to near or below historical lows during the drought periods 2007–2009 and 2012–present. <br><br> Long-term groundwater-level and land-subsidence monitoring in the SJV is critical for understanding the interconnection of land use, groundwater levels, and subsidence, and evaluating management strategies that help mitigate subsidence hazards to infrastructure while optimizing water supplies.https://www.proc-iahs.net/372/23/2015/piahs-372-23-2015.pdf |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
M. Sneed J. T. Brandt |
spellingShingle |
M. Sneed J. T. Brandt Land subsidence in the San Joaquin Valley, California, USA, 2007–2014 Proceedings of the International Association of Hydrological Sciences |
author_facet |
M. Sneed J. T. Brandt |
author_sort |
M. Sneed |
title |
Land subsidence in the San Joaquin Valley, California, USA, 2007–2014 |
title_short |
Land subsidence in the San Joaquin Valley, California, USA, 2007–2014 |
title_full |
Land subsidence in the San Joaquin Valley, California, USA, 2007–2014 |
title_fullStr |
Land subsidence in the San Joaquin Valley, California, USA, 2007–2014 |
title_full_unstemmed |
Land subsidence in the San Joaquin Valley, California, USA, 2007–2014 |
title_sort |
land subsidence in the san joaquin valley, california, usa, 2007–2014 |
publisher |
Copernicus Publications |
series |
Proceedings of the International Association of Hydrological Sciences |
issn |
2199-8981 2199-899X |
publishDate |
2015-11-01 |
description |
Rapid land subsidence was recently measured using multiple
methods in two areas of the San Joaquin Valley (SJV): between Merced and
Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent
land-use changes and diminished surface-water availability have led to
increased groundwater pumping, groundwater-level declines, and land
subsidence. Differential land subsidence has reduced the flow capacity of
water-conveyance systems in these areas, exacerbating flood hazards and
affecting the delivery of irrigation water.
<br><br>
Vertical land-surface changes during 2007–2014 were determined by using
Interferometric Synthetic Aperture Radar (InSAR), Continuous Global
Positioning System (CGPS), and extensometer data. Results of the InSAR
analysis indicate that about 7600 km<sup>2</sup> subsided 50–540 mm during
2008–2010; CGPS and extensometer data indicate that these rates continued or
accelerated through December 2014. The maximum InSAR-measured rate of 270 mm yr<sup>−1</sup> occurred in the El Nido area, and is among the largest rates ever
measured in the SJV. In the Pixley area, the maximum InSAR-measured rate
during 2008–2010 was 90 mm yr<sup>−1</sup>. Groundwater was an important part of the water
supply in both areas, and pumping increased when land use changed or when
surface water was less available. This increased pumping caused
groundwater-level declines to near or below historical lows during the
drought periods 2007–2009 and 2012–present.
<br><br>
Long-term groundwater-level and land-subsidence monitoring in the SJV is
critical for understanding the interconnection of land use, groundwater
levels, and subsidence, and evaluating management strategies that help
mitigate subsidence hazards to infrastructure while optimizing water
supplies. |
url |
https://www.proc-iahs.net/372/23/2015/piahs-372-23-2015.pdf |
work_keys_str_mv |
AT msneed landsubsidenceinthesanjoaquinvalleycaliforniausa20072014 AT jtbrandt landsubsidenceinthesanjoaquinvalleycaliforniausa20072014 |
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