2012 Emergency Track, Emergency Preparedness: Using Local and Federal Data and ArcGIS to Analyze Potential Human and Economic Impacts of Flooding, Valerie Johnson

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Emergency Preparedness:Emergency Preparedness: Using Local and Federal Data and ArcGIS to Using Local and Federal Data and ArcGIS to

Analyze Potential Human and Economic Analyze Potential Human and Economic Impacts of FloodingImpacts of Flooding

Valerie Johnson, Valerie Johnson, [email protected]@reno.gov, Sept. 21, 2012, Sept. 21, 2012Pennsylvania State University MGIS ProjectPennsylvania State University MGIS Project

Advisor: Karen SchuckmanAdvisor: Karen Schuckman

Reno-Tahoe Airport, 1997 Flood Downtown Reno, 2005 FloodDowntown Reno, 2005 FloodPhoto Source: Truckee River Flood Management Project

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OutlineOutline

What This Presentation CoversWhat This Presentation Covers

Brief Background of Flooding in Reno, Nevada Brief Background of Flooding in Reno, Nevada

Project Goals and Information for StaffProject Goals and Information for Staff

Examples of Visualization ProductsExamples of Visualization Products

Methodology and DataMethodology and Data

Spatial DatasetsSpatial Datasets

Property Building ValuesProperty Building Values

Online American FactFinder for Downloading Online American FactFinder for Downloading Demographic Data from the 2010 Census and Demographic Data from the 2010 Census and the American Community Survey (ACS) for the American Community Survey (ACS) for Census TractsCensus Tracts

Special Steps in ExcelSpecial Steps in Excel

Resources About Census DataResources About Census Data

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This presentation covers howThis presentation covers how GIS professionals can:GIS professionals can:

Perform overlay analyses of spatial and Perform overlay analyses of spatial and demographic data from federal and local data demographic data from federal and local data sources to identify potential human and economic sources to identify potential human and economic impacts of flooding (or other emergency).impacts of flooding (or other emergency).

Obtain and prep data from the 2010 Census and Obtain and prep data from the 2010 Census and the American Community Survey. the American Community Survey.

Create visualization products that show the results Create visualization products that show the results in a format that emergency responders and in a format that emergency responders and decisiondecision--makers can easily understand. Maps, makers can easily understand. Maps, charts, and tables are wellcharts, and tables are well--suited for conveying suited for conveying such information in a short, targeted report.such information in a short, targeted report.

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Truckee River FloodingTruckee River Flooding

The Truckee River flows The Truckee River flows from Lake Tahoe in from Lake Tahoe in California and through the California and through the hearts of the adjacent cities hearts of the adjacent cities of Reno and Sparks in of Reno and Sparks in Nevada, before it ends in Nevada, before it ends in Pyramid Lake.Pyramid Lake.

The Truckee River has a The Truckee River has a significant damaging flood significant damaging flood event about every 10 years.event about every 10 years.

117117--year flood in 1997 year flood in 1997 caused damages ofcaused damages of $650 $650 -- $700 million. $700 million.

5050--year flood in 2005 year flood in 2005 caused damages ofcaused damages of $18 million.$18 million.

Downtown Reno, 1907 Flood. Bridge, built in 1905, is still in use.

Photo Source: Truckee River Flood Management Project

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Area of InterestArea of Interest

Truckee River

East of City of Sparks, a narrow canyon

constricts the river

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Project Goals Project Goals ---- Info for Emergency Info for Emergency Response Staff Response Staff ……

Identify facilities and populations that may at Identify facilities and populations that may at risk and require special public safety response risk and require special public safety response (elderly, very young, limited resources)(elderly, very young, limited resources)

Important facilities (schools & colleges, day care, Important facilities (schools & colleges, day care, medical care, hotels, government buildings, fire medical care, hotels, government buildings, fire stations, police stations, etc.)stations, police stations, etc.)

Population (total; under 5 yrs; over 65 yrs)Population (total; under 5 yrs; over 65 yrs)

Population with disability Population with disability –– Unfortunately, data are Unfortunately, data are currently unavailable at the Tract levelcurrently unavailable at the Tract level

Household income (median; household income Household income (median; household income under $15,000/yr)under $15,000/yr)

Transportation (households without a vehicle)Transportation (households without a vehicle)

Your community may want other categoriesYour community may want other categories

LocalData

Census Bureau

Data

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…… and for Decisionand for Decision--MakersMakers

Identify cityIdentify city’’s current building values and s current building values and property taxes for parcels in flood extents property taxes for parcels in flood extents (financial impact of damages)(financial impact of damages)

Buildings that could be damaged by a floodBuildings that could be damaged by a flood (not condos on 2(not condos on 2ndnd and higher floors)and higher floors)

Assessed values of buildingsAssessed values of buildings

Net property taxes for entityNet property taxes for entity

LocalProperty

Appraiser/ Assessor

Data

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Example Example –– Important FacilitiesImportant Facilities

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Example Example –– Population 65+Population 65+

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Example Example –– Income < $15,000Income < $15,000

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Example Example –– No VehiclesNo Vehicles

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Example Example –– Assessed Building ValuesAssessed Building Values

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Example Example –– Snapshot of NumbersSnapshot of Numbers

(Numbers in Table and on Maps are Maximums (Numbers in Table and on Maps are Maximums –– See Caveat Later)See Caveat Later)

Total Population:Total Population: 63,86963,869

Population 5 and Under:Population 5 and Under: 3,6513,651

Population 65 and Older:Population 65 and Older: 9,4939,493

Population 85 and Older:Population 85 and Older: 1,1221,122

Households With No Vehicle:Households With No Vehicle: 4,1454,145

Households With Income $15,000 and Less:Households With Income $15,000 and Less: 4,0364,036

Building Values in 1997 Flood Extent:Building Values in 1997 Flood Extent: Assessed:Assessed: $284,504,502$284,504,502 Net Tax Reno:Net Tax Reno: $9,735,535$9,735,535

Building Values in 2005 Flood Extent:Building Values in 2005 Flood Extent: Assessed:Assessed: $182,845,258$182,845,258 Net Tax Reno:Net Tax Reno: $5,081,778$5,081,778

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Methodology and DataMethodology and Data

1.1. Acquire spatial data and reAcquire spatial data and re--project as needed.project as needed.

2.2. Perform overlay analyses (select by location) to select:Perform overlay analyses (select by location) to select:A.A. Census Tracts intersecting city limits polygon and the 1997 Census Tracts intersecting city limits polygon and the 1997

flood extent (1997 and 2005 extents = same selection)flood extent (1997 and 2005 extents = same selection)B.B. Important facilities intersecting combined flood extent.Important facilities intersecting combined flood extent.C.C. Parcels intersecting each flood extent.Parcels intersecting each flood extent.

3.3. Download CSV files of Census 2010 and American Download CSV files of Census 2010 and American Community Survey (ACS) data. Review and manipulate Community Survey (ACS) data. Review and manipulate tables in Excel. tables in Excel. (This is time(This is time--consuming!)consuming!)

4.4. Use ArcGIS to join Excel file to the Tracts shapefile.Use ArcGIS to join Excel file to the Tracts shapefile.

5.5. Use ArcGIS to create maps. Use Excel to create charts and Use ArcGIS to create maps. Use Excel to create charts and tables. Get feedback from staff about what they want to see.tables. Get feedback from staff about what they want to see.

6.6. Produce short, targeted report. Maintain it!Produce short, targeted report. Maintain it!

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Spatial DataSpatial Data Used in AnalysisUsed in Analysis

Business data (2010 Business data (2010 InfoUSA point data)InfoUSA point data)

Census Tracts (ACS dataCensus Tracts (ACS data is only at Tract level, not is only at Tract level, not Block Group or Block)Block Group or Block)

City limitsCity limits

Flood extents from 1997Flood extents from 1997 and 2005 eventsand 2005 events

Government buildingsGovernment buildings

Medical care facilities Medical care facilities (hospitals, nursing homes)(hospitals, nursing homes)

Parcels with building valuesParcels with building values

Schools, colleges, day careSchools, colleges, day care

Hydrographic dataHydrographic data (river, lakes, and creeks)(river, lakes, and creeks)

Street centerlines &Street centerlines & major roadsmajor roads

Your community may want Your community may want other featuresother features

Spatial DataSpatial Data Used Only on MapsUsed Only on Maps

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Spatial DataSpatial Data

Acquire data from local and federal agencies.Acquire data from local and federal agencies.

Check the coordinate system of spatial dataCheck the coordinate system of spatial data and reand re--project as needed.project as needed.

YouYou’’ll need the Census Tract polygons because the ll need the Census Tract polygons because the American Community Survey (ACS) data is available American Community Survey (ACS) data is available down to the Tract level (not Block Groups or Blocks).down to the Tract level (not Block Groups or Blocks).

Local or state GIS Clearinghouses probably have the Local or state GIS Clearinghouses probably have the Tract polygons. If not, download a shapefile of the Tract polygons. If not, download a shapefile of the 2010 Tracts from:2010 Tracts from:

http://www.census.gov/geo/www/tiger/http://www.census.gov/geo/www/tiger/

The Census Bureau also has a shapefile that includes The Census Bureau also has a shapefile that includes some demographic info from the SFsome demographic info from the SF--1 form 1 form (population, age, race).(population, age, race).

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http://www.census.gov/geo/www/tiger/http://www.census.gov/geo/www/tiger/

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Why? “Select by Location” will select the entire Tract polygons (black outline) that intersect the flood polygons.

Beware - Selected polygons are shown with magenta outline. Unwanted polygons like 31.01 may be selected, so check results!

Select by Location Select by Location …… and Caveatand Caveat

Use Select by Location to get Tracts that intersect the flood Use Select by Location to get Tracts that intersect the flood extent polygon. Caveat extent polygon. Caveat –– Boundaries of Tracts donBoundaries of Tracts don’’t t coincide with boundaries of flood extents, so the count of coincide with boundaries of flood extents, so the count of people/households people/households ““inin”” the flood extent will be larger than the flood extent will be larger than reality (theyreality (they’’ll be the maximum scenario).ll be the maximum scenario).

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About Differences Between theAbout Differences Between the 2000 Census and the 2010 Census2000 Census and the 2010 Census

The 2000 Census included a shortThe 2000 Census included a short--form questionnaire form questionnaire (data tables SF(data tables SF--1 & SF1 & SF--2) and a long2) and a long--form form questionnaire (data tables SFquestionnaire (data tables SF--3 & SF3 & SF--4). 4).

Starting with 2010, the decennial Census now includes Starting with 2010, the decennial Census now includes only the shortonly the short--form questionnaire, covering topics like form questionnaire, covering topics like population, age, and race.population, age, and race.

Form longForm long--form info like marital status, income, number form info like marital status, income, number of vehicles, and disability* are covered in the more of vehicles, and disability* are covered in the more frequently conducted ACS (smaller sample size).frequently conducted ACS (smaller sample size).

See See ““ResourcesResources”” for links to useful documents, for links to useful documents, especially discussions about ACS Margin of Error (+/especially discussions about ACS Margin of Error (+/--).).

* Disability data from ACS 5* Disability data from ACS 5--year estimates slated to be available after 2012. year estimates slated to be available after 2012.

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Obtaining Demographic DataObtaining Demographic Data

Use Census BureauUse Census Bureau’’s s American FactFinderAmerican FactFinder. Go . Go to factfinder2.census.govto factfinder2.census.gov

Under Under ““GeographiesGeographies””, , pick pick ““Census TractCensus Tract””

Then choose your state, Then choose your state, county, and county, and ““All Census All Census Tracts within CountyTracts within County””

Click Click ““Add to Your Add to Your SelectionsSelections””

Then close the popThen close the pop--up up windowwindow

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Demographic Data (continued)Demographic Data (continued)

Can narrow search by typing in a topic (e.g., Income)Can narrow search by typing in a topic (e.g., Income) or type in a specific table number.or type in a specific table number.

The next slide lists the table numbers I found useful.The next slide lists the table numbers I found useful.

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Census Table Numbers Used for RenoCensus Table Numbers Used for Reno

QT_P1 (QT_P1 (““Age Groups and Sex: 2010Age Groups and Sex: 2010””, 2010 SF1), 2010 SF1)

S1901 (S1901 (““Income in Past 12 MonthsIncome in Past 12 Months””,, 2010 ACS 52010 ACS 5--year estimates)year estimates)

B08201 (B08201 (““Household Size by Vehicles AvailableHousehold Size by Vehicles Available””, , 2010 ACS 52010 ACS 5--year estimates)year estimates)

1122

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Preview Table Before DownloadingPreview Table Before Downloading

Preview of B08201 Preview of B08201 –– Number of VehiclesNumber of Vehicles

If the table has the info you want, download it.

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DownloadDownload CSV FileCSV File

Download CSV Download CSV (zipped file).(zipped file).

““In a Single FileIn a Single File”” is is fine.fine.

In Excel, you will In Excel, you will have to rename have to rename column headings, column headings, so if you think you so if you think you will want to refer to will want to refer to original column original column headings, then headings, then choose choose ““Separate Separate FilesFiles””..

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Prep CSV Tables in ExcelPrep CSV Tables in Excel

First, save CSV file as an Excel file. UseFirst, save CSV file as an Excel file. Use a meaningful file name; keep table name in it.a meaningful file name; keep table name in it.

Change table Change table –– Rename headings in first row, delete Rename headings in first row, delete blank & unneeded rows, maybe delete unneeded blank & unneeded rows, maybe delete unneeded columns, and change field typescolumns, and change field types

Table B08201 Table B08201 –– Number of Vehicles Number of Vehicles –– in Excelin Excel

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Prep CSV Tables in Excel (continued)Prep CSV Tables in Excel (continued)

Change table Change table –– Rename headings, delete blank & Rename headings, delete blank & unneeded rows, maybe delete unneeded columns, unneeded rows, maybe delete unneeded columns, and change field types (see next slide)and change field types (see next slide)

Could name this GEOID instead of ID2.

Rename field headings (short and meaningful).

In this field, use “Find and Replace” to remove unwanted text, leaving only the Tract number, for labeling polygons on a map.

Include “ACS” or “2010” referring to source.

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Change ID Field Types in ExcelChange ID Field Types in Excel

In order to join tables in In order to join tables in ArcMap, must change the ArcMap, must change the field containing unique tract field containing unique tract number (number (““ID2ID2””) from a ) from a numbernumber field to a field to a text text field.field.

““Format CellsFormat Cells”” to Text typeto Text type will not work! will not work!

Instead, select a column, Instead, select a column, then go to then go to ““Data > Text to Data > Text to ColumnsColumns””. Choose . Choose ““DelimitedDelimited””, then click , then click ““NextNext””. Choose . Choose ““TabTab””, then , then click click ““NextNext””. Choose . Choose ““TextText””, , then click then click ““FinishFinish””..

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Join Tracts Shapefile With Excel TableJoin Tracts Shapefile With Excel Table

Add Tracts polygon shapefile and Add Tracts polygon shapefile and Excel table to ArcMap.Excel table to ArcMap.

RightRight--click on the Tracts layer and click on the Tracts layer and choose Join.choose Join.

Unique field with Tract numbersUnique field with Tract numbers in the 2010 Tracts layerin the 2010 Tracts layer is called GEOID10.is called GEOID10.

Field in table to join is 2Field in table to join is 2ndnd field field (name depends on what you (name depends on what you named it).named it).

Keep matching records.Keep matching records.

Export to new shapefile.Export to new shapefile.

Remove Join. Repeat as needed.Remove Join. Repeat as needed.

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Visualize DataVisualize Data

Make maps, charts, and tables Make maps, charts, and tables that emergency response staff that emergency response staff will find useful.will find useful.

For map symbology, choose For map symbology, choose Quantities > Graduated Colors. Quantities > Graduated Colors. For Fields > Value, choose For Fields > Value, choose category you want to show.category you want to show.

For classification, start with For classification, start with default default ---- Natural Breaks Natural Breaks (Jenks). Then click Classify to (Jenks). Then click Classify to adjust adjust ““Break ValuesBreak Values”” to ones to ones easily recognized.easily recognized.

Get staff feedback on drafts.Get staff feedback on drafts.

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Resources About Census DataResources About Census Data

Census Handbook Census Handbook ““A Compass for Understanding and A Compass for Understanding and Using American Community Survey Data Using American Community Survey Data –– What State and What State and Local Governments Need to KnowLocal Governments Need to Know””:: http://www.census.gov/acs/www/guidance_for_data_users/handbooks/http://www.census.gov/acs/www/guidance_for_data_users/handbooks/

Short ESRI Slideshow about differences between decennial Short ESRI Slideshow about differences between decennial census and ACS, as well as Margin of Error:census and ACS, as well as Margin of Error: http://www.slideshare.net/CCIMTECH/esrihttp://www.slideshare.net/CCIMTECH/esri--20102010--censuscensus--andand--acsacs

Slideshow produced by Tufts University GIS Center about Slideshow produced by Tufts University GIS Center about using Censususing Census’’s American FactFinder website and s American FactFinder website and downloading data, as well as changing headers and rows downloading data, as well as changing headers and rows of the downloaded CVS tables in Excel:of the downloaded CVS tables in Excel: https://wikis.uit.tufts.edu/confluence/display/GISatTufts/Tufts+https://wikis.uit.tufts.edu/confluence/display/GISatTufts/Tufts+GIS+TipSGIS+TipS heets+ArcGIS10heets+ArcGIS10 (under (under ““Census DataCensus Data””, click link to , click link to ““Census Tutorial: Census Tutorial: Downloading and Mapping American FactFinder Data Downloading and Mapping American FactFinder Data …”…”

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WhatWhat’’s Next For This Project?s Next For This Project?

Create a short, targeted report.Create a short, targeted report.

Check back in a few months for ACS 5Check back in a few months for ACS 5--year year estimates about population with a disability. estimates about population with a disability.

Keep data tables, maps and report updated as Keep data tables, maps and report updated as new ACS data becomes available.new ACS data becomes available.

Downtown Reno, Normal Early Summer River FlowPhoto Source: Truckee River Flood Management Project