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Floodplain Figure 15 shows the areas identified within the 100 -year flood zone according to the National Flood Insurance Program maps dated May 17, 1982. The 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. FEMA 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 occurring in 2012 by 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 Resource Management Plan (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, satellite -based estimation of impervious surface area and Green -Ampt infiltration methodology. The majority of the 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 balance 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 specific 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 overflows under a 100 -year event (Figure 16). In addition, the RMP identifies flooding concerns by Resource Management Unit (Table 5). City of Lino Lakes SWMP 1 February 8, 2013 Draft 1 34 •