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I factors. 'The storm sewers draining under the low point convey runoff from about 38 acres of Comm ercial and 2 residential development. Storm water coming out of the storm sewer pipes or"surcharging"' at these catch I basins causes floloiding. , Street flow running down Larpenteur due to pipe surcharge of other storm sewer 4 ;and/or- catch basins also exacerbates this flooding. High water in Gottfried Pit slows and inhibits drainage. 5 Once the elevation of the Pit reaches 908, the street begins to flood. The modeled high water elevation in 6 Larpenteur Avenue aftler. a I 00-yr design storm is 916.6 1. the field verified elevation of the street flooding 7 after a 4.5 inch 9 hour storm event on June 24, 2003 was 911.61. In late 2004, Capitol Region Watershed completed the Cotino 7 subwatershed hydrologic evaluation in preparation for the City of St. Paul street reconstruction project. Gottfried Pit and the Fernwood/ Larpenteur low point were studied as a part of this evaluation. The report did not identify an. engineerIng solution that would, completely eliminate the flooding, of the Larpenteur Avenue low point. However, it did recommend the installation of SCADA at the Gottfried flit lift station. A S,CADA (Supervisory Control And Data Acquisition) system enables the City to monitor the lift station remotely, It will also alert us when the. water elevation of the Pit reaches pre- programmed elevations. This, will be installed later this year. The cost is shared by Falcon Heights, Sit, Paul, Ramsey County and Roseville according to the contributing sub-watershed area., In our 20016 storm water report, presented to the City Council in February, we added Gottfried Pit as a CSWMP problem area. This enables the City to require the developer to incorporate such practices as are necessary to resolve their proportionate share of the flooding problem in the subwatershed. This will incrementally resolve flooding concerns in this subwatershed. City Staff will be requiring all redevelopments, to, construct runoff rate control/ volurnie reduction best management practices. Eventually, this will alleviate some of the flooding at the Fernwood/Larpenteur low point. however, it ""Fill take many years. , Since this building is in. the problem area subwatershed, volume reduction is being required of as a part of'' the building permit approval for Gold Eagle,. Policy ffisicussl*oin We have discussed this matter with the building owner. He is very interested in moving forward with his addition and does not fe�el that we should be applying the CSINMP policies to his addition since it is a pre- existing structure. He has indicated that he has only experienced flooding in the building once after the 1987 super, storm, which was an extreme rain event, rain totals, around the City ranged from 6 to 8 inches. Gottfried Pit was expanded in the 1990"s, and his building has not been flooded since. Be is asking that we allow them to move forward with the addition and is willing to indemnify the City should a rain event occur that causes, the street flooding to damage any portion of his building or private property. The City Attorney has reviewed the applicable city codes regarding the CSW policies. He has advised staff that deviation from these policies does not fall, under the usual variance procedures, City Code 110 16.26132, simply states, that the City Engineer shall certify that a proposed plan is in compliance with the pity's I I y's C:SWMP. Because of freeboard policies, I do not feel that I can do this without implementing policy 1.8,. As described above, Policy 1.8 allows that when flood protection is not possible we should develop an emergency response plan. Due to the potential liability to the City as the result of flood damage to the new structure and other private property, staff felt that this issue should be brought to the City Council for discussion. 46 Financial Implicafiloinis 47' If the owner indeninifies the City from any damages to his property, due to flooding in this subwatershed, there should be no future financial implications for the City.