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I I I I I I I I I I I I I I I I I I I AYRES ._~--_. - -- Developing the Resource Atlas will be a two-fold process. Initially, the Resource Atlas will be developed around existing spatial data sources described in the request for proposals. These existing datasets will provide the base map for the Atlas. It is assumed that the available data sources are in varying coordinate systems and of varying quality. This initial step will require converting all data to a common coordinate system and may require converting from one file type to another. As the project progresses, the Atlas will continue to be enhanced with data from the subsequent tasks defined in the scope of work. This will include hydrologic data developed under Task 3. Hydraulic data developed under Task 4 will be primarily on the separately developed mapping base proposed as Optional Task 7. As described for Task 4, results from 2-dimensional modeling can be used to create innovative themes for the GIS such as color coded water surface contours, velocity contours, and streamlines for various modeled flow conditions. The Resource Atlas will need to support visualization and analysis at both a regional (basin-wide) and local level. Examples of basin-wide datasets include the IFSAR digital elevation data, existing hydrography, and road information from COOT. Other datasets, such as those made available by the City and County, will describe local features such as property information, infrastructure, and other urban features. Once all of this data is incorporated into the GIS base map, we propose establishing predetermined maps or views for displaying the data. This would allow for quick creation of paper maps to be disseminated to stakeholders or to the public at meetings and presentations. One view would focus on the entire basin, highlighting the regional setting and features of interest. Other views would focus on local areas of interest, such as illustrating streamlines at a bridge crossing or the interaction of the 100-yr floodplain with property boundaries. We also propose setting up sheets that follow the alignment of the channel. These can be easily printed to create a "paper" Resource Atlas of the creek, its floodplain, and all other spatial features in the GIS. We have done this for several projects and found it to be a useful tool. For the Corps of Engineers, we assembled an atlas of the Sacramento River using GIS that catalogs bank erosion sites for more than 200 miles of river channel. During their yearly reconnaissance, the Corps takes the paper copies into the field to mark changes and then updates the GIS back in the office. Along the Lower American River, we developed similar mapping to show the results of hydraulic modeling and illustrate impacts to fish habitat and spawning areas. The GIS will be assembled so that other data types such as photos, video, field notes, historic database records, reports, etc., can be linked to the overall Resource Atlas. These data types can be converted to digital format and linked to geographic locations in the GIS so that they are accessible by a simple click of the mouse. We will explore the availability of such data sources when talking with those agencies and governments listed in the scope that will provide the base map data. Ayres Associates employs ESRI's ArcGIS software, including ArcView (both 3.x and B.x versions), Spatial Analyst, and 3D Analyst. We regularly use ArcView software as a tool to view and analyze data, convert data from one file-type or coordinate system to another, develop maps and graphics, interact with database information, perform hydrologic and hydraulic analyses, work with 3-dimensional data (OEM, TIN, DTM), and display features located using GPS methods. Through project experience we 11