Item talk:Q229493

{

 "@context": "http://schema.org/",
 "@type": "WebPage",
 "additionalType": "Project",
 "url": "https://www.usgs.gov/centers/nevada-water-science-center/science/delineation-flood-inundation-areas-grapevine-canyon",
 "headline": "Delineation of Flood-Inundation Areas in Grapevine Canyon near Scotty\u2019s Castle, Death Valley National Park, California",
 "datePublished": "June 8, 2017",
 "author": [
   {
     "@type": "Person",
     "name": "Christopher  Morris",
     "url": "https://www.usgs.gov/staff-profiles/christopher-morris",
     "identifier": {
       "@type": "PropertyValue",
       "propertyID": "orcid",
       "value": "0000-0002-0477-7605"
     }
   }
 ],
 "description": [
   {
     "@type": "TextObject",
     "text": "A rain gage at Scotty\u2019s Castle recorded 2.72 in of precipitation over a five-hour period."
   },
   {
     "@type": "TextObject",
     "text": "The most recent flood-inundation map for the area was published in 1989 and delineated the 4, 2, and 1-percent annual exceedance probability (AEP) flood areas (25, 50, and 100-year return intervals, respectively) for lower Grapevine Canyon and Tie Canyon based on discharge computed using regional flood regression equations from Waananen and Crippen. The water level for the October 18, 2015, flood rose to the 1-percent AEP flood elevation at Scotty\u2019s Castle, with a computed flow of 12,000 cubic feet per second (cfs), as defined by previous work by Bowers. After channel surveys and hydraulic computation, the NVWSC determined a peak flow for the event of 3,200 cfs. The computed discharge corresponded to the 4 to 2-percent AEP based on updated regional flood frequency regressions in Gotvald and others. These most recent regression equations compute significantly less flow (35-40%) than the previous equations that were used by Bowers for the 4, 2, and 1-percent AEP."
   },
   {
     "@type": "TextObject",
     "text": "NVWSC installed crest-stage gages in Grapevine and Tie Canyons to collect peak flow data. Scour chains have been installed near both CSGs to determine if significant scouring and filling is occurring during peaks."
   },
   {
     "@type": "TextObject",
     "text": "The October 18, 2015, indirect measurement and the 1989 mapping determined the channel to be in a super-critical flow regime. The combination of super-critical flow, shallow depths, a very steep channel, and erodible channel bed material, results in an unstable channel with significant scour and fill during floods. Channel instability has been demonstrated by scour at the entrance of the Castle Gate bridge during the 2015 flood, significant fill deposited by an unnamed tributary wash between channel cross-sections X2 and X5 during the 2015 flood, and overflow scour at the parking lot observed by NPS personnel in July 1976."
   },
   {
     "@type": "TextObject",
     "text": "Weather radar suggested 3-4 in of precipitation elsewhere in the lower part of the drainage basin during the same event, which the National Weather Service estimated to be a \u201c1,000-year rainfall event\u201d."
   },
   {
     "@type": "TextObject",
     "text": "The thunderstorm on October 18, 2015, triggered flooding in Grapevine Canyon."
   },
   {
     "@type": "TextObject",
     "text": "On October 18, 2015 an intense, nearly stationary, thunderstorm triggered flooding in Grapevine Canyon. Grapevine Canyon Road, power and water infrastructure, and several buildings at Scotty\u2019s Castle were damaged by the flood water, necessitating closure of the area to the public. In response to the flood event, the National Park Service requested the USGS Nevada Water Science Center perform a channel survey and hydraulic computation of peak flow for the event and update the information on current channel conditions to delineate the flood-inundation area of Grapevine Canyon and Tie Canyon near Scotty\u2019s Castle."
   },
   {
     "@type": "TextObject",
     "text": "Scotty\u2019s Castle, in the northeast part of Death Valley National Park, lies within the flood-inundation area of Grapevine Canyon near the confluence with Tie Canyon. Grapevine Canyon drains the steep, western slope of the Grapevine Mountains near the Nevada and California state line with a drainage area of approximately 47.9 mi2. Tie Canyon makes up the northwestern part of the Grapevine Canyon basin and has a drainage area of approximately 14.5 mi2. Scotty\u2019s Castle is a popular tourist attraction on the National Register of Historic Places that includes several historically and architecturally significant buildings, in addition to park administration buildings and public water supply and utility infrastructure. Scotty\u2019s Castle is accessible via Grapevine Canyon Road that passes along the entire length of Grapevine Canyon and, in some locations, takes up the entire width of the canyon floor. Several springs are located in Grapevine Canyon that provide surface flow over short distances, but flow in most of the canyon is driven by episodic precipitation."
   },
   {
     "@type": "TextObject",
     "text": "Crest Stage Gages"
   },
   {
     "@type": "TextObject",
     "text": "Significant channel changes have reduced the applicability of the 1989 map to current channel conditions. In order to update the information on current channel conditions, the NVWSC is updating the flood\u2013inundation area map for the 4, 2, 1, 0.5, 0.2-percent AEP floods in Grapevine and Tie Canyons in response to current (2016) channel conditions and the updated regional flood frequency regression equations by"
   }
 ],
 "funder": {
   "@type": "Organization",
   "name": "Nevada Water Science Center",
   "url": "https://www.usgs.gov/centers/nevada-water-science-center"
 },
 "about": [
   {
     "@type": "Thing",
     "name": "Geology"
   },
   {
     "@type": "Thing",
     "name": "Environmental Health"
   },
   {
     "@type": "Thing",
     "name": "Peak Flows"
   },
   {
     "@type": "Thing",
     "name": "Natural Hazards"
   },
   {
     "@type": "Thing",
     "name": "Streamflow"
   },
   {
     "@type": "Thing",
     "name": "Floods, Droughts, and other Hazards"
   },
   {
     "@type": "Thing",
     "name": "Maps and Mapping"
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   {
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     "name": "Energy"
   },
   {
     "@type": "Thing",
     "name": "Methods and Analysis"
   },
   {
     "@type": "Thing",
     "name": "Information Systems"
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   {
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     "name": "Hydrologic Research"
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     "name": "Methods and Analyses"
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     "@type": "Thing",
     "name": "Remote Sensing"
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     "name": "Spatial Analysis"
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   {
     "@type": "Thing",
     "name": "Water"
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   {
     "@type": "Thing",
     "name": "Flood and Drought Science"
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     "name": "Science Technology"
   },
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     "@type": "Thing",
     "name": "Numeric Modeling and Advanced Technologies"
   }
 ]

}