montana height modernization curt smith national geodetic survey idaho phone: 208-332-7197 montana...

MontanaHeight

ModernizationCurt SmithNational Geodetic SurveyIdaho Phone: 208-332-7197Montana Phone: 406-444-0989Curt.Smith@noaa.gov

State of Vertical Control

Heights Matter!

DESCRIPTION: The Santa Clara River flows past destroyed homes and a fallen tree in the Creek side subdivision Wednesday in St. George. Seven homes in the subdivision were completely lost to the river and at least another four were severely damaged by this week's flooding. CREDITS: Jud Burkett COPYRIGHT: The Spectrum

Southern Utah Flooding 1/12/2005

DESCRIPTION: A row of damaged homes in Riverwood subdivision cling to the banks of the Santa Clara River Thursday in St. George.

CREDITS: Jud Burkett COPYRIGHT: The Spectrum

Southern Utah Flooding 1/12/2005

North Carolina Floodplain Mapping

2002 Detail Mapping vs.

Effective Approximate

Mapping

Poured in place concrete post

1954

Stainless steel rod driven to refusal

1980’s

PhysicallyMonumented

Points

Current Survey Control

NGS Data Sheetwww.ngs.noaa.gov

NGS Bench Marks

Disturbed Geodetic ControlCoordinates/Elevations

Questionable

Destroyed Geodetic ControlNo Coordinates/Elevation

Monumented PointsDeterioration

USGS Topographic Map

F 143 Not recovered (destroyed)

E 143 Not recovered (destroyed)

D 143 Not recovered (destroyed)

C 143 Not recovered (destroyed)

2nd Order Vertical1st Order Vertical

684 - Total Vertical Control Points Listed

Lewis and Clark County Vertical Control Pointsin NGS Database

Lewis and Clark County Vertical Control Points in NGS Database

684 - Total Vertical Control Points Listed

176 (25.7%) – Missing 65 - Reported as Destroyed111 - Reported as Not Found

508 (74.3%) – Possible Vertical Control Points146 – Total Monumented (no recovery notes)

20 – Reset 1 – Set Within Last 10 Years

362 (52.9%) – Total Recovered in Good Condition112 – Recovered for NAVD88 (after 70’s) 64 – Recovered Good Within Last 10 Years