R2009-213 AUTHORIZING CITY MANAGER TO NEGOTIATE WITH COUNTY OF MACON

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MANAGEMENT SERVICES DEPARTMENT MIS DIVISION Memorandum No.2009-08 October 30,2009 MEMO TO: Honorable Mayor McElroy and City Cguncil i�ffn�� FROM: Ryan P.McCrady, City Manager ��r Keith D.Alexander,Director,Water Management Department �/�- David S. Johnston,Manager,MIS Division'`�� Brad J. Boesdorfer, Senior Systems Analyst,MIS Division �� SUBJECT: Elevation Data Acquisition SUMMARY RECOMMENDATION: Staff recommends that Council authorize the City Manager to execute an Intergovernmental Agreement with Macon County for the purchase of electronic elevation data. BACKGROUND: Elevation data,usually in the form of contour lines or topographic maps,provides city engineers the ability to plan and analyze site projects. Effectively designing and constructing roads and bridges, sewer and water systems,and flood and drought mitigation infrastructure requires comprehensive understanding of landform slope and grading. Typically,a field crew and survey equipment is required at each project location to gather this elevation information. Light Detection and Ranging(LiDAR)technology,however, offers elevation acquisition quickly and at lower cost for large areas. A plane is flown over an area while electronics on board pulse millions of beams of light at the ground below;the sensors on the plane measure the length of time it takes the light pulses to bounce back and calculates the elevation. Using the LiDAR method would take two days of flights to acquire contour and topographic data for all of Macon County;the data would be returned as points spaced every 3 feet on the ground that are +/-6" accurate vertically. This would eliminate most preliminary surveys for future sewer and water projects, saving both personnel time and money, and would allow more effective and faster design analyses by outside consultants and state and federal agencies. Public Works Engineering Division supports this project and looks forward to using the data gained on future water and storm drainage improvement projects. Macon County staff requires this information for many of their same projects, and has agreed to partner with the City to fund LiDAR acquisition. Based on its geographic area,the City has been asked to contribute$15,000 towards the roughly$200,000 project. It is staffs recommendation that Council authorize the City Manager to spend no more than$15,000 in an intergovernmental agreement with Macon County for the purpose of acquiring LiDAR-based electronic elevation data. POTENTIAL OBJECTIONS: None anticipated. INPUT FROM OTHER SOURCES: None. STAFF REFERENCE: Brad J.Boesdorfer, Senior Systems Analyst,MIS 450-2218. BUDGET/TIME IMPLICATIONS: Funding for this expenditure is provided for in the approved FY 2009-10 Water Non Lake Capital budget. 1