TITLE: FLORIDA DEPARTMENT OF TRANSPORTATION NOISE ABATEMENT BARRIERS

Geodataset Name:       NOISE_BARRIERS
Geodataset Type:       SHAPEFILE
Geodataset Feature:    LINE

This dataset contains the Florida Department of Transportation's (FDOT) noise abatement barriers.

DATA SOURCE(S):                    Florida Department of Transportation
				   Environmental Management Office
SCALE OF ORIGINAL SOURCE MAPS:     1:2500
DATE OF AUTOMATION OF SOURCE:      2004
GEODATASET EXTENT:                 State of Florida

FEATURE ATTRIBUTE TABLES:

Datafile Name: NOISE_BARRIERS.DBF

FEATURE ATTRIBUTE TABLES CODES AND VALUES:

Item	Item Description
FID	Internal feature number.
Shape	Feature geometry.
NBID	Key identifer created by CUES. The Key Identifier developed for this project is a combination of FDOT's multiple unique identifiers including identifiers that distinguish each individual District office as well as the county the wall is located in. See Noise_abatement_barriers.doc
ROADWAY	Roadway characteristic ID index
ROAD_DESCR	RCI roadway description
G_LENGTH	Length generated by GIS
STATE_FIPS	Statewide FIPS code
FDOT_DISTR	FDOT district ID
COUNTY_FIP	County FIPS code
COUNTY_F_1	County FIPS code 2
RCI	Roadway characteristic index from 2000 inventory
WALL_ID	Wall ID - 2000 inventory
SECTION_	Section - 2000 inventory
BARRIER_ID	Barrier ID - 2000 inventory
WPI_ID	WPI_ID - 2000 inventory
CONTRACTOR	Contractor
YR_BUILT	Year built
MATERIAL	Construction material
LEN_METER	Length in meters
LEN_FEET	Length in feet
HGT_METER	Height in meters
HGT_FEET	Height in feet
AREA_METER	Area in meters
AREA_FT	Area in feet
OVERLAP	Overlapping walls
TOTAL_COST	Total cost
COST_MET	Cost per meter
COST_FT	Cost per feet
PREDICTED	Predicted
MEASUE	Measure
COMMENTS	Comments
FM_ID	Derived from D6 fields - Recommended fields by D6
BEGIN_POST	Derived from D6 fields
BEG_X	Derived from D6 fields
BEG_Y	Derived from D6 fields
END_POST	Derived from D6 fields
END_X	Derived from D6 fields
END_Y	Derived from D6 fields
COUNTY_NAM	County name
PIC	Pic hyperlink to path
PDF_LINKS	PDF hyperlink to path
AUTOID	Internal ID
DESCRIPT	FGDL added field based on ROAD_DESCR
SHAPE_LEN	Shape length

USER NOTES:

GeoPlan relied on the integrity of the attribute information within the original data.

Noise Barriers were compiled based upon locational information in the FDOT - Noise Barrier Status Report, June 2000. Based upon telephone interviews and surveys, the Noise Barriers in Districts 1, 2, 5, and 7 were identified. District 4 Noise Barriers were collected via GPS and provided as a line feature class and point feature class within a personal geodatabase from District 4. District 6 collected the start and end nodes for each wall via GPS and provided the information as a point feature in Shapefile format. Relative scale was utilized as opposed to field measurements that define absolute scale. This is not to say GPS technology was excluded, in fact during this project, nearly every barrier was identified and/or verified using a Trimble GXT. However, the X/Y coordinates collected through the use of GPS were no longer positionally aligned relative to the scale used for FDOT FGDL layers. Therefore, spatial editing was used to adjust the positional location of the barriers to align them to based upon the relative accuracy of the existing GIS layers The Noise Abatement Barriers personal geodatabase has attributes that can be related to Roadway Characteristics Inventory (RCI) data with the 'ROADWAY' field.

A note concerning data scale: Scale is an important factor in data usage. Certain scale datasetsare not suitable for some project, analysis, or modelling purposes. Please be sure you are using the best available data. 1:24000 scale datasets are recommended for projects that are at the county level. 1:24000 data should NOT be used for high accuracy base mapping such as property parcel boundaries. 1:100000 scale datasets are recommended for projects that are at the multi-county or regional level. 1:250000 scale datasets are recommended for projects that are at the regional or state level or larger. Vector datasets with no defined scale or accuracy should be considered suspect. Make sure you are familiar with your data before using it for projects or analyses. Every effort has been made to supply the user with data documentation. For additional information, see the References sectionand the Data Source Contact section of this documentation. For more information regarding scale and accuracy, see our web pages at: http://www.geoplan.ufl.edu/education.html

REFERENCES:

Detailed metadata provided by CUES: Noise_abatement_barriers.doc Contact Christina Bryk Center of Urban and Environmental Solutions (CUES) Florida Atlantic University 111 East Las Olas Blvd, Suite 709 Fort Lauderdale, Fl 33301 (954) 762-5255 / Fax: (954) 762-5666 Center for Urban Environmental Solutions: http://www.cuesfau.org/ http://www.cuesfau.org/projects/project.asp?ProjectID=107 FDOT June 2000 Noise Barrier Status Report (Spreadsheet) Contact win.lindeman@dot.state.fl.us for details.

DATA LINEAGE SUMMARY:

Primary Data Collection - GPS In late May 2004, the Center for Urban and Environmental Solutions deployed a field team to ground-truth the original 30 noise abatement walls in the June 2000 Report. Utilizing a Trimble GeoXT with GPS correct for real-time post-processing, the field team collected GPS information to verify the location of these barriers. During the GPS field work, three (3) new walls were identified in District 1 along the I-4 Corridor, the GPS information was collected for these walls as well. Once research staff confirmed these were owned by FDOT, they were included into the Statewide Noise Abatement Geodatabase. GPS coordinates were collected by the research field team for 33 noise abatement walls. District 4 and District 6 indicated that they would be initiating their own GPS collection during the summer and fall of 2004. Rather then replicate this effort, CUES coordinated with these two districts to obtain the completed GPS information and import it into the Statewide Geodatabase. However, approximately seven walls were not included in these two Districts inventories. Therefore, CUES field team used GPS to collect wall information mainly for the Sawgrass Expressway and the Florida Turnpike. Overall GPS coordinates were collected for 40 walls by CUES. The internal setting of the GeoXT's GPS were set to ensure the highest possible accuracy. The settings utilized are as follows: · PDOP: (Position Dilution of Precision) : 6 or less · SNR (Signal To Noise Ratio): 4 · Elevation Mask: 15% · Number of Satellites: 4 or Higher · Differential Correction: WAAS Each noise barrier wall in the region was surveyed to obtain both spatial, attribute and photographic information necessary for the project. Upon arrival to the particular barrier wall, the team would investigate the following conditions before undertaking the survey: · Traffic volume & Safety conditions · Survey Obstacles · GPS Satellite Visibility · GPS Availability Upon arrival to the location, traffic volume was determined by the amount of traffic traveling adjacent to the wall of interest. The estimated volume determined whether it was judged safe for a foot survey or required use of a vehicle. Hard hats and florescent safety vests were worn at all times while conducting the surveys. Numerous barrier walls surveyed had large swaths of vegetation planted next to them. Major types of vegetation included: Sable Palm trees, Sea Grape and various other bushes. These vegetation lines often followed the length of the given wall an ranged on an average from 10-75 feet. Since many of the walls had some type of vegetation, an offset was incorporated into the survey. Generally all surveys were done on an average of 20 feet in front of the wall. Many of the walls not only had a vegetation line in front but also a layer of standing water. This situation occurred in areas where the walls possessed a gully or depression directly in front of the vegetation line. In many situations, the accumulated water actually formed a small linear wetland including typical wetland flora and fauna which included unfortunately high concentrations of biting insects. If these water bodies existed, the offset was increased to account for the additional obstacle so that the survey could continue. Other barriers to the survey included manmade structures such as tollbooths, embankments, bridges and narrow walks. If such obstacles were encountered, the situation was noted in the attribute table and the offset increased as needed. GPS is a line of sight technology which relies on the ground based receiver the ability to have a clear and unobstructed line of sight to the GPS satellites. Noise barrier walls provide a unique problem in that they can obstruct half of the sky depending on how close the survey is conducted to them. Due to this fact, an offset was also needed to obtain the best possible satellite lock. GPS uses a measurement called PDOP (Position Dilution of Precision) to indicate accuracy. To ensure high accuracy GPS positioning, it is recommended that the PDOP value be less than 6. During all wall surveys, PDOP was monitored very closely and any measurement greater than 6 was resurveyed. Once the Noise Barrier Wall was cleared to survey, the walking team member would activate the Mobile GIS/GPS unit and begin logging the poly-line feature. At the beginning of the logging, an initial starting coordinate would be relayed to the vehicle team member for input into handwriting log. If a walking Survey was done, the survey team member would walk the length of the wall with the vehicle team member following along to provide a look out for traffic. At the halfway point of the survey, the walking team member would again call out the coordinate of the middle of the wall to the vehicle team member. Once the entire length of the wall had been traversed, the walking team member would stop the logging and fill in the custom input form in the ArcPad software. Digital photos were also taken at each survey location. After each wall was surveyed, the team would back up the data on the GeoXT mobile device and then download the data onto a laptop computer. This procedure was completed at the location incase data was lost and the survey would have to be redone. Once back at the office, all data for that day was downloaded onto the project server to be used by the GIS section. Acquisition from individual districts of walls in GIS format according to interviews conducted during this project among FDOT personnel, at the time of interviews, District offices were not maintaining an inventory of their noise barriers in GIS. However, in the summer and fall of 2004, two District offices used GPS technology to store their noise abatement walls in GIS. District Four utilized GPS to store both the point (begin/end points) and line feature classes representing 95 noise abatement walls. District 4 provided the research team with their personal geodatabase. Next, the point and line feature classes were merged and spatially projected into the Statewide Geodatabase. District 4 also created a hyperlink to the photos collected during their GPS work. This hyperlinkis included as part of the Statewide Geodatabase. District 6 utilized GPS technology to capture the begin node and end node for each wall. However, no line feature classes were created. Utilizing the GPS begin and end nodes, the research team digitized the line feature class representing the noise barriers for approximately 84 out of 96 total walls in District 6. A Trimble GeoXT was used to collect the points and linear features depicting the remaining 12 barriers. On Screen (Heads-up) Digitizing This spatial data collection technique, based on utilizing high quality, rectified aerial photos and other georeferenced GIS layers, was used primarily to edit the spatial data collected through GPS for relative positional accuracy purposes. The level of accuracy of the derived dataset is taken from the initial accuracy of the digital image along with georeferenced GIS layers. One of the challenges was to utilize aerial photos in GIS at an acceptable resolution needed to create and edit spatial features for all District offices that have noise abatement walls. The central problem is that most ortho photos in GIS are collected by county governments who collected this raster information at varying scales, different data formats (e.g. MrSID, TIF, JPEG, SDE) and/or captured at different time frames. Based upon these challenges as well as the degree of acquiring these raster features, it was decided to utilize ESRI's ArcWeb Services. One of ArcWeb Services offered is access to GlobeXplorer's 'Citipix/Digital Ortho' which was used to perform the spatial edits required to verify and/or're-align' the GPS collected data relative to scale of FDOT's GIS base map layers. Citipix is the largest high-resolution aerial imagery dataset available online through ArcWeb Services. Captured at six-inch resolution and in 24-bit color, Citipix is precision geo-referenced and ortho-rectified. It covers over 7,000 cities and towns in over 73 metropolitan areas in the United States, with a total area of over 90,000 square miles. Because of Citipix high resolution, it provided the optimal back ground layer to digitize, edit, and verify the linear features representing the walls. Using GPS points collected by District 6 which represent the begin and end nodes for each wall along with GlobeXplorer's digital orthophotography, the line feature classes for these walls were digitized. 96 out of the 217 walls within the Statewide Geodatabase were digitized. District 6 accounts for approximately 44% of all noise barriers in the Statewide Geodatabase. Process Date: 20040101 GeoPlan took the data from the Statewide Noise Barrier GeoDatabase two disk set in May 2005. The layer was called NBGD_ALL and located in the Feature Dataset NBGD of the FDOT_NAB_GDB.mdb (on disk 1). This feature class was in Albers HPGN. A DESCRIPT field was added and based on the field ROAD_DESCR. The AUTOID field was created and calculated as a unique number. Process Date: 20050501

MAP PROJECTION PARAMETERS:

Projection                          ALBERS
Datum                               HPGN
Units                               METERS
Spheroid                            GRS1980
1st Standard Parallel               24  0  0.000
2nd Standard Parallel               31 30  0.000
Central Meridian                   -84 00  0.000
Latitude of Projection's Origin     24  0  0.000
False Easting (meters)              400000.00000
False Northing (meters)             0.00000

DATA SOURCE CONTACT (S):

Name:

Abbr. Name:
Address:


Phone:

Web site:
E-mail:
Contact Person:
         Phone:
        E-mail:

Florida Department of Transportation
Environmental Management Office
FDOTEMO
605 Suwannee Street
Tallahassee, FL
32399
1-866-374-3368 ext. 4447


http://www.dot.state.fl.us/emo/
peter.mcgilvray@dot.state.fl.us
Mariano Berrios

Name:                   FLORIDA GEOGRAPHIC DATA LIBRARY
Abbr. Name:             FGDL
Address:                Florida Geographic Data Library
                        431 Architecture Building
                        PO Box 115706
                        Gainesville, FL  32611-5706
Web site:               http://www.fgdl.org

Contact FGDL: 

      Technical Support:	        http://www.fgdl.org/fgdlfeed.html
      FGDL Frequently Asked Questions:  http://www.fgdl.org/fgdlfaq.html
      FGDL Mailing Lists:		http://www.fgdl.org/fgdl-l.html
      For FGDL Software:                http://www.fgdl.org/software.html