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City of Lino Lakes SWMP | February 8, 2013 Draft | 34 Floodplain Figure 15 shows the areas identified within the 100 -year flood zone according to the National Flood Insurance Progr am maps dated May 17, 1982 . T he City has a Floodplain Ordinance in accordance with Federal Emergency Management Agency (FEMA ) and Department of Natural Resources (DNR ) requirements to minimize potential losses due to periodic flooding along these areas. F EMA is currently updating the Flood Insurance Rate Maps for the Lino Lakes area. Hydrologic and hydraulic modeling has been conducted throughout the City for many previous efforts (Appendix A ). The most recent and detailed modeling is occurr ing in 2012 b y RCWD. This updated hydrologic and hydraulic model was provided to FEMA to assist in floodplain studies. A previous XP - SWMM (Storm Water Management Model) model update was completed in 2007 in support of the Lino Lakes R esource M anagement P lan (RMP ). This model is capable of completing multi -year continuous simulation for the years 1999 -2003 or event simulation depending on the needs of the user. Most ponds, water bodies, and wetlands within Lino Lakes have been explicitly modeled as a live storage volume with an outlet allowing a high resolution of results and analysis. The hydrologic inputs to the model were based on 2 -foot contours, s atellite -based estimation of impervious surface area and Green -Ampt infiltration methodology. The majority of th e channels and ponds were surveyed with some use of as - built drawings on newer developments. Upstream inputs from major tributaries were input directly into the XP -SWMM model using the regional HydroCAD model for event based simulations and a water balanc e approach for continuous simulation for the years 1999 -2003. The model can be used for the simulation of any synthetic rainfall/runoff event up to the 100 -year 24 -hour event. Larger events are possible but have not been tested. The RMP identifies spec ific areas of flooding concern under a full buildout scenario and implementation of RMP 2.8 -inch infiltration standards. The study identified areas where the road would be overtopped, where less than 1 foot of freeboard is expected, and where a pond overf lows under a 100 -year event (Figure 16 ). In addition, the RMP identifies flooding concerns by Resource Management Unit (Table 5 ).