Final Project

Our final project took a lot of time and effort and really made us take everything we've learned all semester to produce a well-polished product. Our assignment was to take the role of a GIS Analyst hired as a consultant by Florida Power and Light (FPL) to perform GIS analysis for the proposed Bobwhite-Manatee transmission line. We were given several criteria and we were to produce maps and analysis to determine if the criteria were met satisfactorily by the FPL preferred route. We were then to create a Powerpoint presentation to explain our process and conclusions. The maps for this project were produced entirely in ArcMap.

Criteria #1: It has relatively few homes in close proximity. This criteria is put in place due to the concerns of some that electromagnetic radiation could be hazardous to your health. For this assignment, "close proximity" is within 400 feet. For the map I created to demonstrate compliance with this criteria, I added the aerial imagery provided, the FPL preferred corridor, and created a buffer layer 400 feet outside the FPL preferred corridor. To identify homes, I had to create another layer using the Georeferencing toolbar to digitize the structures that were homes. I zoomed in and out, starting at the top of the corridor (and buffer) areas and placed a point wherever I believed there was a home either within the buffer or the corridor. I created another field in the attribute table and labeled it "1" if the home was within the corridor or "2" if it was within the buffer (but outside the corridor). The most difficult part of this was identification of homes. The ones with swimming pools in the backyard were somewhat obvious, but there were some structures that I discounted because they were too large to be a home (and didn't appear to be an apartment complex) or were in an industrial area. If I was still unsure, I erred on the side of caution and digitized the structure as a home. Once I had this layer on my map, I used the symbology of a green point for homes within the corridor and a white point for homes within the 400 foot buffer but outside the corridor. There are relatively few homes impacted, so this criteria appears to be well satisfied. We also want to minimize our impact on land parcels, so I created a second map showing this. I added the land parcels of Manatee and Sarasota counties. I used the Intersect tool to separate this into parcels from each county within the FPL corridor and within the 400 foot buffer, and displayed this on my map. We can see that many more parcels are affected in Manatee County than in Sarasota County. Much of this appears to be either public land or, at the very least, not a major impact on homeowners due to the small number of homes impacted. Regardless, the number of parcels impacted is a main factor in my cost analysis definition of suburban land (as opposed to rural land).

Criteria #2: It generally avoid schools and school sites. Again, our criteria is here due to health concerns of electromagnetic radiation, so we can fortunately use the same 400 foot buffer used to evaluate the first criteria. For this map, I still have the FPL corridor and the buffer layer, but now I have separate school and daycare sites layers added. As this data was for the entire state, I clipped it to the extent of the study area, which I displayed as a line fill feature which I think shows the area well. I showed the schools in the study area as a red school symbol and the daycares as a green school symbol. I did not need to clip this to within the buffer or corridor regions, as there are clearly none there. This route is an excellent choice based on this criteria.

Criteria #3: It avoids large areas of environmentally sensitive lands. To evaluate this criteria, I ended up creating 2 maps. First, I wanted to show the land parcels identified as conservation land as it compared to the area within the FPL preferred corridor. I clipped the conservation land layer to the extent of the study area, and also to the extent of the preferred corridor. The red polygons within the FPL corridor are where the corridor encroaches onto conservation land. The main point of this map is to show that within the study area there are over 14,000 acres of conservation land, but the FPL Preferred Corridor only encroaches on 164 acres on conservation land. The second map I created focused on displaying the wetlands and uplands in the study area and the corridor. I clipped the wetlands (and uplands) to the extent of the study area, and employed the same technique to the extent of the FPL corridor. I categorized the wetlands into lakes, swamps and marshes, and rivers using the attribute table and I made each category easily distinguishable. To determine the acreage within the FPL preferred corridor, I used the Select by Attributes feature and selected that wetland type. Notice that of the 19,000 acres of wetlands in the study area, the FPL corridor goes through approximately 900 acres. Based on both these maps, the FPL Preferred Corridor does indeed manage to avoid large areas of environmentally sensitive lands.

Criteria #4: This line can be built along this route for a reasonable cost. For the cost estimate, I had to rely heavily on the .pdf about cost of transmission lines provided on the course website. On this map, I show the study area and the FPL preferred corridor. To first determine the length of the new line, I zoomed in closely to the map and, starting at the top of the corridor, found the centerline and used the Measure tool. I traced the centerline to the bottom extent of the corridor and determined that the length of the new transmission line will be just under 25 miles. I drew a line on my map showing the length of the route. To provide a cost estimate, I used the .pdf provided to determine that it will cost $1,100,000 per mile. This value depends on the line being single circuit and using tubular steel pole construction. I categorized the area as a suburban area, as it crosses through a moderate number of land parcels, which multiplies the cost of the transmission line by 1.2 times. The new line is over 20 miles long, so no extra cost is attributed to the length of the line. This gave me a total engineering and construction cost of the new Bobwhite-Manatee transmission line to come out to $32,760,000. This seems to be a reasonable value, and the transmission line route is relatively straight, so I believe that this is one of the least expensive routes for the new line.

Conclusions: Based on the four criteria, this seems to be an excellent route for the new Bobwhite-Manatee transmission line. There are few homes and schools in the area, it minimizes its impact on land parcels and environmentally sensitive land, and it appears to be a very efficient route.

We also needed to create a Powerpoint presentation and a slide-by-slide summary, which you can see in the hyperlink below.

Alan Hickford Final Presentation

Slide-by-slide summary of Final Presentation