FR Exam 2 Substitute Project!!!!!!! 1

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1 FR Exam 2 Substitute Project!!!!!!! 1 Goal We seek to identify county lands that both protect vernal pools and riparian corridors, and that provide open space and recreation within easy reach of urban dwellers in western Placer County, California. Note that data are provided or will be downloaded in various coordinate systems. You should convert all data to UTM, NAD83(1986), Zone 10N coordinates first. You'll need an NAD83 to WGS84 datum transformation - you'll need to investigate to decide on which one to use, but as a hint, it isn't #1 or #2. Look in the instructions or documents provided earlier in class, or perhaps more quickly, check the ESRI help forums via ArcMap help or a web search. You should also note that while some data are already clipped to the study area boundary, most are not - you should clip all data to the study area boundary at some point in your analysis, but after you have projected them to the common coordinate system. Note that you'll be applying a moving window process to the raster landcover data, so this might affect when/how you clip. Data Sets Study_Bound: a polygon shapefile defining the area of interest. CityLimits: a polygon shapefile of city and town limits for a region encompassing the study area (there are extra city limits you'll have to remove). Cities_Study: Point shapefile of city center locations. Roads: Major roads in a line shapefile, for a region encompassing the study area. Placer_tracts: U.S census boundary shapefile defining block groups. Note that the tract identifier is listed in the item tractid, and the block group identifier in the item BGroup. Placer_bgpop.dbf: a table containing the population for each block group, in item P The item placer_bgc is a key that is a composite of the block group number, in the right most digit, and the tract identifier, in the leftmost 5 digits, e.g., is tract 20101, block group 1, is tract 20105, block group 4, etc. To join this table to Placer_tracts, you must first construct a key in Placer_tracts that matches this key. Placer_soils: a polygon shapefile of SURGO soils from the NRCS. The primary key is mukey_n RestrictSV.dbf: a table of soil properties, with the key for linking to Placer_soils in item mukey. fwswetlandsextract: a geodatabase, with wetlands polygon data in the wetlands feature class. These data are only available for a portion of the study area.

2 FR Exam 2 Substitute Project!!!!!!! 2 NASSWGS84: a raster landcover dataset, with number codes for a detailed list of landcover types (needed values provided later in these instructions). Please note that any resampling of the land cover data should be nearest neighbor, and you should maintain the 56 x 56 meter cell size for the NASS data set. Existing_sites: polygon parcels to be analyzed in a comparison to your selected parcels. NHD streams and rivers data: You are not provided, but will find and download, data for streams and rivers flowlines from the medium-resolution, national hydrologic dataset (NHD) series of the USGS. One source source is the USGS NHD data data servers, found via This first link opens a viewer, and near the bottom of the left-most column in the viewer is a link labeled "how to extract." If you follow the instructions, you may download by various areas, including counties. The instructions describe how to download by subbasins, if you follow these, the subbasin set , , , , covers the area. If you download by county, use Placer County. Note that on writing this I've tested it with various browsers, and it seems to work with Firefox, Internet Explorer, and Safari, but is a bit of a balky interface, so have patience. Remember that the "active" list of round buttons on the right hand column, under the Hydrologic Units and Base Map Features tabs define the regions you're selecting by - e.g., counties, sub-basins. The squares check boxes are to set the visibility for features. Note, I couldn't get the newer NHD/USGS viewer the site references to work reliably. You may also download from the the second link, on the page nhd.usgs.gov/data.html. The link is titled "Go to Pre-staged Subregions," but a word of caution. This appears to work only with the Internet Explorer browser, and then not all the time. If it works it will display a directory, through which you can navigate to the medium resolution flowlines data for the basin with code 1802, covering our area. Another source is from the GIS Data Depot, at data.geocomm.com/catalog, login under pbolstad, 5131exam and retrieve via California, County Wide Data, Placer, National Hydrological Dataset - medium (1:100K), HUC subregion You may use other download sites if you wish, as long as you download the correct data. Goals Your goal is to produce maps and tabular data depicting potential open space park sites. You should apply the criteria listed below, noting that the term "will include" means these potential sites are non-exclusively added to the set of potential sites, while "must" or "must not" means the condition is obligatory to all potential locations. For example, sites do not have to be both near wetlands (criterion 2) and near NHD

3 FR Exam 2 Substitute Project!!!!!!! 3 flowlines (criterion 3). If the site is within the buffer one or the other, or both, they are considered candidates. However, none of the final potential sites may be outside the study boundary (criterion 1), nor may any sites be farther than 3 kilometers from urban areas (criterion 6). Read the "wills" and "musts" in the other criteria accordingly. Also, please note that you will have been taught almost all of the functions you need to complete this project in labs by lab 11. Those you haven't been taught are similar to one's covered. Remember, most of the vector overlay, buffer, and extract are in ArcToolbox - Analysis Tools, and most of the raster tools are in ArcToolbox-Spatial Analyst Tools. Also think about the selection tools, subsetting, and analysis tools available through the Table of Contents, Spatial Analyst, and Tables/Selection toolbars/ menus. In doing your work, remember, there may be many ways to the correct answer. If you try a new tool, or apply a covered one, it often helps to verify manually that it works as you expect by examining the input and output for a small subset of your area, e.g., looking at individual cells and polygons. Criteria 1) Sites must be within the Study_Bound area. 2) Sites must not be within a city limit boundary 3) Sites will include areas within 300 meters of a wetland with Wetland_Type of "Freshwater Emergent Wetland." This buffer includes the interior, wetland areas. 4) Potential sites will include areas within 150 meters of the NHD Flowlines with the FType that identifies streams and rivers. 5) Potential sites will include areas with high likelihood of vernal pools. These occur on soils with a restricting layer near the surface. The file RestrictSV.dbf (which you'll need to join to the Placer_soils polygons) contains information on restricting layers. In our case, layers with a value of "Duripan", "Lithic Bedrock", or "Paralithic Bedrock" in the restriction item, AND with values <50 in the topdepth item are those likely to have large numbers of vernal pools. 6) Potential sites must NOT be in areas currently developed for intensive farming and housing/commercial uses. This translates to means potential sites have NASS landcover types with Value items of 37 (other hay), 59 (seed/sodgrass), 61 (fallow/idle), 62 (pasture/grass), 63 (woodland), 64 (shrubland), 65 (barren), 87 (wetland), 131 (NLCD Barren), 141, 142, 143 (NLCD forest classes), 152 (NLCD shrubland), 171 (NLCD grassland/herb), 181 (NLCD pasture/hay), or 190 (NLCD Woody Wetlands). This is a reclassification on the DATA (e.g., look in the Spatial Analyst Toolbox). You should remove the small isolated areas and random noise in the landcover data. After you have subset the cells in the above classes, you should apply a focal statistics

4 FR Exam 2 Substitute Project!!!!!!! 4 function (found in the Arctoolbox under Spatial analyst tools, Neighborhood), using the 5x5 rectangle, and a median statistics type. 7) Potential sites must be within 3 kilometers (km) of urban areas. DO NOT use city limits to define urban areas - some urban areas are outside city limits, and some areas within the city limits are not urban. Define urban areas from a reclassification of the NASS landcover data. Include code 82 (urban/developed), and 121 through 124 (NLCD developed classes). As with criterion 5, above, remove "speckle," use a median focal statistic, this time with a 15 x 15 rectangular neighborhood to smooth the data. Note that potential sites within 3 kilometers must not include the urban areas themselves, you may need to remove them from the buffered area after you buffer, depending on how you arrived at this 3 km zone. 8) Potential sites must not be within block groups that have a population density greater than 50 people/square kilometer. Previous experience shows that both prices and NIMBY reaction makes these poor candidate areas. 9) You have to identify the potential areas by two classes - those between 0 and 1 kilometer of the "urban areas" defined in criterion 6, above, and those between 1 and 3 kilometers from the urban areas. We will want the areas of the polygons in the next step, so you must dissolve all "internal" boundaries in the potential areas within each of these two distance categories. To be clear, you'll have just three types of polygons - those that are not potential sites, those potential sites from 0 to 1 km out, and those potential sites from 1 to 3 km out. There must be no boundaries separating polygons of the same class. 10) Finally, we are interested in contiguous blocks not bisected by major roads. Intersect the layers you've arrived at that meet all criteria 1 through 9, with the polylines road layer. One way is to convert the polylines in the Roads.shp layer to polygons ) ArcToolbox - Data Management Tools - Features - Features to Polygons), but note that you may have to do some editing of the output, or Union the output with the study boundary to get a complete set of polygons covering the entire study area. Create a column to hold the area in square kilometers for this final set of polygons. Make sure you can hold up to 3 values to the right of the decimal point. Calculate the area, in square kilometers, into this column. Identify the largest polygons in each of the 0 to 1, and 1 to 3 km distance from urban areas. Create a layer identifying them, and note the area in square kilometers, where prompted below. 11) Finally, there is one parcel in the northern part of the study area, and one in the west, that have been purchased by the county land commission already. Calculate the minimum travel time to each of these parcels from the cities in the study area, assuming the travels cost is 0.85 minutes per kilometer on the major roads depicted in the

5 FR Exam 2 Substitute Project!!!!!!! 5 Roads.shp layer, and 6 minutes/kilometer for all other areas. Also calculate the travel time to each of the largest parcels selected in 10, above, in the 0 to 1 kilometer distance class and 1 to 3 distance class from urban areas. To answer 11, you'll need to calculate the cost distance, found in the ArcToolbox - Spatial Analyst Tools - Distance - Cost Distance. You will have to create a raster for the cost per unit travel (the friction raster), with the travel time costs as indicated above. Along each road, the cost should be 0.85, off the roads the cost is 6, and within the target parcels, set the cost at something very small...e.g., So, this raster will combine data from the roads, Existing Sites polygons, your largest polygons from 10, above, and the study boundary polygons, somehow combined, attributed, and converted to a raster. Use a cell size of 10 meters or smaller for the raster. You will also need to set all the cities as the feature source, and use them in the cost distance calculations. Note the minimum cumulative travel cost that comes from this function for each parcel, and note it where indicated in the answers, below. Outputs While doing these analyses, answer the following questions (all units in square kilometers, measured in UTM NAD83 zone 10N coordinates). Unless explicitly stated, all the questions below should be answered for the area within the Study Area, as defined by the Study_Bound polygon. What is the area of the study area? What are the total number of Freshwater Emergent Wetlands in the study area? What is the total area of Freshwater Emergent Wetlands in the study area? What is the total area in the study area within 300 meters of Freshwater Emergent Wetlands, including the wetlands? What is the total area, within the study area, of land within 150 meters of an NHD flowline stream/river?

6 FR Exam 2 Substitute Project!!!!!!! 6 How many soil polygons are potential areas for vernal pools in the study area? What is the total area? Within the study area defined by the Study_Bound polygon, what is the total area that is in suitable NASS landcover types (not developed or intensive agriculture in criterion 5) before your median smoothing? What is the total area that is in suitable NASS landcover types (not developed or intensive agriculture in criterion 5) after your median smoothing? What is the total urban area from NASS landcover types (criterion 6) before your median smoothing? What is the total urban area from NASS landcover types (criterion 6) after your median smoothing? What is the total area within 3 kilometers of your urban area (criterion 6)? What is the number of block groups with a population density less than or equal to 50 persons/square kilometer? What is the total area for the above set of block groups? What is the number of block groups with a population density greater than 50 persons/ square kilometer? What is the total area for the above set of block groups?

7 FR Exam 2 Substitute Project!!!!!!! 7 What is the total number of distinct polygons meeting all of your suitability criteria? Note by distinct I mean suitable polygons that don't share a boundary (i.e., after a dissolve on suitability). What is the summed (total) area of polygons meeting your suitability criteria? What is the summed area of suitable polygons from 0 to 1 kilometers of your urban area? What is the summed area of suitable polygons from 1 to 3 kilometers of your urban area? What is the area of the largest suitable parcel, unsplit by roads, in the 0 to 1 km zone? What is the area of the largest suitable parcel, unsplit by roads, in the 1 to 3 km zone? What is the travel time, in minutes, to the largest potential recreation parcel in the 0 to 1 km zone, from a city? What is the travel time, in minutes, to the largest potential recreation parcel in the 1 to 3 km zone from a city? What is the travel time, in minutes, to the northern "Existing parcel?" What is the travel time, in minutes, to the western "Existing parcel?"

8 FR Exam 2 Substitute Project!!!!!!! 8 Maps and Data to Turn in Each map should be complete with a title, your name, a legend, scale bar, and north arrow. All data on maps should be clipped to the study area only, and include an unfilled (no color) outline of the study area boundary, and a clipped NHD flowlines layer. Maps to Submit Turn in the following maps, as pdfs, to the course Moodle site. In all cases, the order of the data stack is listed from top to bottom, e.g., in the first map, wetlands should be on top of the wetland buffer. Please combine all these pdfs in a single zip file, so you are uploading only one file of maps. 1) Freshwater emergent wetlands, wetland buffer, NHD stream/river flowlines, study area boundary. 2) NHD streams/rivers, stream buffer, study area boundary 3) Soil polygons likely to have vernal pools, NHD stream/rivers, study area boundary 4) NHD streams/rivers, acceptable vegetation after smoothing (from criterion 5), study area boundary. 5) NHD streams/rivers, urban areas after smoothing (from criterion 6), areas < 1 km from urban areas, areas from 1 to 3 km from urban areas, study area boundary. 6) NHD streams/river, block groups, and include the layer for study area boundary. The block groups layer should be colored in two categories, i] those 0 to 50 people/square kilometers, and ii] those greater than 50 persons/square kilometer 7) NHD streams/rivers, potential park areas in two classes (and different colors), i] those in areas from 1 to 3 km from urban areas, and ii] those less than 1 km from urban areas, the urban areas layer, and the study area boundary. 8) NHD streams/rivers, potential park areas for the largest polygons in each of the 0-1, and 1-3 km classes, and the two "largest parcels," one from the 0 to 1 km zone, and 1-3 km zone. Remember, these are the largest parcels left after the ares have been bisected by the roads layer.

9 FR Exam 2 Substitute Project!!!!!!! 9 Data to Submit Please submit a combined zip file of your shapefiles/data layers for 1) wetlands buffer 2) stream/river buffer 3) soil polygons likely to have vernal pools, 4) block groups with a column for population density, in persons per square kilometer 5) your urban areas 6) acceptable landcover types (non intensive agriculture, non-urban) 7) your final set of candidate sites 8) the two largest potential parcels, one each for the 0-1 km, and 1-3 km zones 9) The travel time grid layer, containing the time, in minutes, to travel from a city to the "Existing Parcels" areas. Please don't include any additional data in the zip file, and make the names descriptive, e.g. "wetland_buff," not "layer1_buffer." Answer Sheet Please submit the answer sheet, first downloading the blank provided in MSWord format on the course website, with your answers in the appropriate boxes.