u.s. department of the interior u.s. geological survey height modernization coordination meeting...

U.S. Department of the InteriorU.S. Geological Survey

Height Modernization Height Modernization Coordination MeetingCoordination Meeting

Paul H. Rydlund Jr. PLSPaul H. Rydlund Jr. PLSU.S. Geological SurveyU.S. Geological SurveyMissouri Water Science CenterMissouri Water Science Center

USGS Publication For USGS Publication For Vertical ControlVertical Control

Inter-agency Datum Inter-agency Datum Establishment And Establishment And Conversion Collaboration Conversion Collaboration

In MissouriIn Missouri

USGS GNSS T&M – Why?USGS GNSS T&M – Why?

• Technique and Approach Guidance For USGSTechnique and Approach Guidance For USGS• Accuracy and PrecisionAccuracy and Precision• MetadataMetadata• Example Campaigns and Decision TreesExample Campaigns and Decision Trees• Future DirectionFuture Direction• Consistent and ReferableConsistent and Referable

The Black Box

Global Navigation Satellite System

“With the new Trimble

R8 systems, we are

getting vertical accuracies

within 7 mm as stated

in the data collector “

“RTK can only be usedwhen setting up directly over a benchmark “

“Real-Time Network

surveys pretty much

guarantee vertical

accuracies within 2 cm

and you never need a

base station “

“All post processing GPS

surveys must ensure 6

hours of data collection at

a minimum“

USGS GNSS T&M - IntroductionUSGS GNSS T&M - Introduction

• Historic USGS Datum EstablishmentHistoric USGS Datum Establishment

• EvolutionEvolution• GPS ModernizationGPS Modernization• GNSS GLONASS, Galileo, CompassGNSS GLONASS, Galileo, Compass

• Geodesy BackgroundGeodesy Background

GNSS T&M - EquipmentGNSS T&M - Equipment

USGS GNSS T&M - Mission PlanningUSGS GNSS T&M - Mission Planning

• PDOPPDOP• MultipathMultipath• Ionosphere & TroposphereIonosphere & Troposphere• Satellite Availability Satellite Availability ((Notice Advisory To Navstar Users)Notice Advisory To Navstar Users)

• Space Weather Space Weather ((Space Weather Prediction Center)Space Weather Prediction Center)

• Resolution and Accuracy of Local GeoidResolution and Accuracy of Local Geoid

Troposphere

Ionosphere

< 10 km > 10 km

LOOKOUT

FOR

THESE

GNSS T&M – Real Time (RT) SurveysGNSS T&M – Real Time (RT) Surveys

•Single Base RTSingle Base RT•Network Base RTNetwork Base RT


•Quality AssurancesQuality Assurances

Blunder CheckBlunder Check1.1.Multipath and GeneralMultipath and General2.2.HeightHeight3.3.ReinitializationReinitialization

Blunder Check -Blunder Check -Let’s sum it up!Let’s sum it up!

Collectively, the GNSS user observes 180 epochs or 3 minutes of data, walks Collectively, the GNSS user observes 180 epochs or 3 minutes of data, walks away from the objective point a minimum of 100 feet, inverts the rover receiver away from the objective point a minimum of 100 feet, inverts the rover receiver (or adjusts the elevation mask) to lose initialization, changes the rover rod (or adjusts the elevation mask) to lose initialization, changes the rover rod height at least 0.80 feet and corrects the rover height entered in the data height at least 0.80 feet and corrects the rover height entered in the data collector appropriately, walks a different approach path back to the objective collector appropriately, walks a different approach path back to the objective point, then positions the rover receiver in an upright position over the objective point, then positions the rover receiver in an upright position over the objective point for the second observation. Both observations are averaged to produce point for the second observation. Both observations are averaged to produce the final result. This process is hereinafter referred to as a RT blunder check the final result. This process is hereinafter referred to as a RT blunder check and should be recorded in the field notes to document that these redundant and should be recorded in the field notes to document that these redundant assurances are met. assurances are met.


• Localizations / RealizationsLocalizations / Realizations

USGS GNSS T&M – Post ProcessedUSGS GNSS T&M – Post Processed

• Single Base – OPUSSingle Base – OPUS• Traditional StaticTraditional Static• Rapid StaticRapid Static

The experts inThe experts ingeodesy.geodesy.

The USGS GNSS T&M Manual The USGS GNSS T&M Manual recommends and encourages use recommends and encourages use of this online utility of this online utility

USGS GNSS T&M – Post ProcessedUSGS GNSS T&M – Post Processed

•Network SurveysNetwork Surveys

•Quality AssurancesQuality Assurances

Modified from NOS NGS 59 Tech Memo

USGS GNSS T&M – Quality CategorizationUSGS GNSS T&M – Quality Categorization

• Level I – Static Network SurveyLevel I – Static Network Survey• ControlControl

• 40 Km spacing; 4 hour; 240 Km spacing; 4 hour; 2ndnd order or better order or better • Objective Objective

• 15 Km spacing; 1 hour; 50% double occupied15 Km spacing; 1 hour; 50% double occupied• Additional benchmark checks other than primary controlAdditional benchmark checks other than primary control

• Level I – Static Single Base Survey (OPUS-S)Level I – Static Single Base Survey (OPUS-S)• OccupationOccupation

• 2 Days, 4 hours, different times2 Days, 4 hours, different times• Quality IndicatorsQuality Indicators


• Level II – Static Network SurveyLevel II – Static Network Survey• Control PointsControl Points

• 60 Km spacing; 4 hour; 260 Km spacing; 4 hour; 2ndnd order or better order or better • Objective PointsObjective Points

• 25 km spacing; 1 hour; 50% double occupied25 km spacing; 1 hour; 50% double occupied• Additional benchmark checks other than primary controlAdditional benchmark checks other than primary control

• Level II – Static Single Base Survey (OPUS-S)Level II – Static Single Base Survey (OPUS-S)• Occupation 1 day – 4 hours Occupation 1 day – 4 hours • Quality IndicatorsQuality Indicators

• Level II – RT SurveysLevel II – RT Surveys• Localization – 2Localization – 2ndnd order or better order or better• Satellites; PDOP; baseline length Satellites; PDOP; baseline length • Blunder check redundancy within 0.03 mBlunder check redundancy within 0.03 m• Objective points 10% double occupied (within 0.05m) Objective points 10% double occupied (within 0.05m)


• Level III – Static Single Base Survey (OPUS-S)Level III – Static Single Base Survey (OPUS-S)• Quality IndicatorsQuality Indicators

• Level III – Static Single Base Survey (OPUS-RS)Level III – Static Single Base Survey (OPUS-RS)• Quality Indicators Quality Indicators

• Level III – RT SurveysLevel III – RT Surveys• Localization – 3Localization – 3rdrd order or better order or better• Satellites; PDOP; baseline length Satellites; PDOP; baseline length • Blunder check redundancy within 0.04 mBlunder check redundancy within 0.04 m• Objective points 10% double occupied; within 0.05mObjective points 10% double occupied; within 0.05m


• Level IVLevel IV• Generally reserved for RT topographic surveys without Generally reserved for RT topographic surveys without checkschecks• Can be composed of static surveys without quality Can be composed of static surveys without quality indicators or checksindicators or checks

USGS GNSS T&M – Quality “How Do We Get USGS GNSS T&M – Quality “How Do We Get There?”There?”

USGS GNSS T&M – Metadata USGS GNSS T&M – Metadata (documentation of the geodetic trail)(documentation of the geodetic trail)

Recovery Establishment• BenchmarkBenchmark

USGS GNSS T&M – Metadata USGS GNSS T&M – Metadata (documentation of the (documentation of the geodetic trail)geodetic trail)

• Observation Observation

• Database storageDatabase storage lat-long and altitudelat-long and altitude metadata metadata

USGS GNSS T&M – Example Data Set USGS GNSS T&M – Example Data Set (Groundwater (Groundwater Well Field)Well Field)

USGS GNSS T&M – Example Data Set USGS GNSS T&M – Example Data Set (Flood Study)(Flood Study)

USGS GNSS T&M – USGS GNSS T&M – Example Data Set Example Data Set (Streamgage Datum)(Streamgage Datum)

USGS GNSS T&M – Future Direction of GNSSUSGS GNSS T&M – Future Direction of GNSS

• Modernization programs – L5 signalModernization programs – L5 signal

• GRAV-DGRAV-D

• Precise Point Positioning (PPP)Precise Point Positioning (PPP)

Plug for USGS – GPS CommitteePlug for USGS – GPS Committee

http://water.usgs.gov/usgs/osw/gps/http://water.usgs.gov/usgs/osw/gps/

Office of Employee Development (OED) ID1747Office of Employee Development (OED) ID1747

Application and Practice of Survey-Grade Application and Practice of Survey-Grade GNSS Real-Time and Static Surveys in the USGSGNSS Real-Time and Static Surveys in the USGS



SyllabusSyllabus



OPUS ProjectsOPUS Projects

PROJECT APPLICATION – PROJECT APPLICATION – Storm Surge Storm Surge Sensors Sensors The New Madrid FloodwayThe New Madrid Floodway

Levee BreachLevee Breach

PROJECT APPLICATION – PROJECT APPLICATION – Storm Surge Storm Surge Sensors Sensors What’s up with Sandy…What’s up with Sandy…

Legacy Datum - Mississippi River Legacy Datum - Mississippi River Datum and Some Datum and Some TributariesTributaries

1.1. Memphis DatumMemphis Datum2.2. Mean Gulf DatumMean Gulf Datum3.3. Fourth General Adjustment of 1912Fourth General Adjustment of 1912

Historic datum is Historic datum is considered legacyconsidered legacy

Legacy Datum – Middle Mississippi Legacy Datum – Middle Mississippi River Datum – St. Louis Gaging River Datum – St. Louis Gaging StationStation

Historic datum is Historic datum is considered legacyconsidered legacy

Middle Mississipppi River Gage Hydralic DatumsDatum Conversions

Zero GageSt Louis Direatrix 413.68 -33.74Cario 400.23 -20.29Memphis 387.10 7.16Mean Sea Level 379.94 St Louis Gage 0Mean Gulf 379.80 0.14Engineers Office 213.68 166.26

NAVD 88 Datum Conversion : Simple Height NAVD 88 Datum Conversion : Simple Height Conversion or Survey – “The USGS Missouri Model”Conversion or Survey – “The USGS Missouri Model”

Cooperative Interest

Cooperative Interest

Gage locationhydraulics or channel instability

1. Evaluation of 1. Evaluation of Source DatumSource Datum

2. Cooperative 2. Cooperative InterestInterest

3. Hydraulics 3. Hydraulics and Stabilityand Stability

4. Accuracy assured4. Accuracy assured with USACE ‘CEPD’with USACE ‘CEPD’ and NWS modeling and NWS modeling interestsinterests

Source Datum genesis and condition

Accuracy

Missouri River Missouri River Datum DiscrepancyDatum DiscrepancyExampleExample

Inter-Agency Collaboration in MissouriInter-Agency Collaboration in Missouri

Benefits of Inter-Agency Collaboration

Enhance ResourcesEnhance Resources

Reduce ExpenseReduce Expense

Quality AssuranceQuality Assurance

Agency ConsensusAgency Consensus Public ApprovalPublic Approval

Continuing Inter-Agency Collaboration in Continuing Inter-Agency Collaboration in MissouriMissouri

Datum Surveys – Moving ForwardDatum Surveys – Moving Forward

USGS and USACE duplicative surveys at important gaging locations Main stem Missouri and Mississippi River gages Water resource operation project gages Limited duplication at tributary gages

USGS / USACE surveys Sharing of metadata and results Overcome cost prohibitive gaging locations Augmenting staff for local/regional GNSS campaigns

USGS Gaging Installation Installation of an observable benchmark

DatumDissemination

Continuing Inter-Agency Collaboration in Continuing Inter-Agency Collaboration in MissouriMissouri Survey assistance….Survey assistance….

NWKNWK

SWLSWL

MVLMVL

MVSMVS

MVMMVM

USACEUSACE

MODOTMODOT

MDNRMDNR

Continuing Inter-Agency Collaboration in Continuing Inter-Agency Collaboration in Missouri – FY 13Missouri – FY 13

Single Base OPUS

Level I Quality - SWL Augment Survey

Gaging Station Number

Gaging Statiion DescriptionObservation

DateTime

Obsevations Used

RequiredAmibiguities

FixedRequired

Solution RMS (m)

Required (m)

Vertical peak-to-peak (m)

Required (m)

Orthometric Height

Average Ortho Height

(m)

Within 0.05m of

each solution

7058000Bryant Creek near Tecumseh,

MO

10/16/2012 1137 - 1703 91% >80% 94% >80% 0.015 <0.030 0.028 <0.06 182.006182.03

0.027

10/17/2012 0746 - 1302 91% >80% 85% >80% 0.017 <0.030 0.076 <0.06 182.060 0.027

7053600Lake Taneycomo at School of

the Ozarks, MO

10/16/2012 1122 - 1701 87% >80% 95% >80% 0.015 <0.030 0.069 <0.06 218.965218.97

0.003

10/17/2012 0725 - 1204 85% >80% 90% >80% 0.017 <0.030 0.027 <0.06 218.971 0.003

7054080Beaver Creek near Bradleyville, MO

10/16/2012 1123 - 1704 91% >80% 93% >80% 0.012 <0.030 0.028 <0.06 252.800252.80

0.001

10/17/2012 0758 - 1358 90% >80% 84% >80% 0.013 <0.030 0.016 <0.06 252.802 0.001

7053810Bull Creek near Walnut

Shade, MO

10/16/2012 1209 - 1753 96% >80% 94% >80% 0.012 <0.030 0.034 <0.06 229.712229.71

0.004

10/17/2012 0716 - 1313 95% >80% 87% >80% 0.013 <0.030 0.035 <0.06 229.704 0.004

7053820Lake Taneycomo at School

Powersite Dam, MO

10/16/2012 1226 - 1747 93% >80% 95% >80% 0.013 <0.030 0.017 <0.06 219.420219.43

0.008

10/17/2012 0806 - 1308 95% >80% 91% >80% 0.013 <0.030 0.017 <0.06 219.435 0.007

USGS Missouri Water Science Center Observations per T&M (Level I)USGS Missouri Water Science Center Observations per T&M (Level I)

USACE – SWLUSACE – SWLUSGS - MOWSCUSGS - MOWSCUSGS - ARWSCUSGS - ARWSC

Continuing Inter-Agency Collaboration in Continuing Inter-Agency Collaboration in Missouri – FY 13Missouri – FY 13

Inter-Agency Collaboration

Datum Surveys – Assistance and CollaborationDatum Surveys – Assistance and Collaboration

http://www.ngs.noaa.gov/ADVISORS/AdvisorsIndex.shtmlhttp://www.ngs.noaa.gov/ADVISORS/AdvisorsIndex.shtml

Inter-Agency Collaboration

[email protected]@usace.army.milDatum Surveys – Assistance and CollaborationDatum Surveys – Assistance and Collaboration

QuestionsQuestions ??

u.s. department of the interior u.s. geological survey height modernization coordination meeting...

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