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17 18 19 2D 21 7z 23 24 25 26 27 28 29 30 3l 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 faetors. The storm sewers drainin� unde:r tlae low poinC co�vey runaff �ram about 38 acr�s of cornrrtercial and residential developmen�. �torm water corz�in� out af the siorrn sewer pipes or "surcharging" at these catch 6asins causes f�ooding. Sfreet flow runninp; down Larpenteur du� to pipe surc�aarge of oth�r storcn sewer and/or ea�ch basins alsa e�acerbates this f�aoding. High water in Gottfried Pit slows and inhibits draina�e. Once the ele�ation of the Pit reaches 908, the stree� begins to �lood. The z�aoc�eled high r�vater eIevation in Larpenteur Ave�ue after a 100-yr design sto:rrr� is 9i6.61, t�e �elci �erifed elevation of t�e street floodir�g after a�.5 inck� 9 hour s�ori� event on .�une 24, 2003 was 911.b. In late 2004, Capitol Region Watershed co�pleted ��e Como 7 subwatershed Y�ydrologic evaluation in preparation for the City p�' S�. Paul street r�cons�ruction praject. Gnttfried �'it and the Fern�vood/ Larpenteur low point were studied as a part of this evalua�ion. The repart did not ide�tify an engineeriz�g solutinn that wo�ld cflax�pletely eliminate tlae flonding of the Larpenteur Avcnue Iaw point. However, it did recornmend the installation of �CADA at the Go�fried Pit IiFt statio�a. A SCADA (�upervisory Cot�trol And Data Acquisi�ionj system enables the City to inonitar tl�e lift station remoteIy. It will also alert us wl�en the water elevatian of tl�e Pit reaehes pre- programmed elevations. This will be installed later tl�is year. The cost is shared b� FaIcon Heigllts, St. �'aul, Ramsey Cocrz�ty and Roseville accorc�ia�g to tne contributing subivatershed area. In our 200G storm water report, presented to the City Ca�zncil in F'ebruary, we added Gottfi•ied Pit as a CSWIVIF' p�roblem area. This enables the City to rec�uire th� develnper ta zncazpo�'ate sucl� practices as are z�ecessary io aresnlve lheir pxoportianate share of the flooding prdblem in �he subwa�ershed. This will increzzaentally re�alve flaodiang cp�xcerns in t�is s�hwatershed. City S�aff will be requiring alI redevelopmenfis to constrtzet runoff rate control/ va��me red�zction best management praciices. Eventual�y, thi� wili alleviate sorne of tkze flaodiiag at the Fernwoocl/Larpenteur ir�w poiz�i, however, it wil� talce znany years. Since this bt�ilciing is in the probl�zxa area subwatershed, vc3lume reduction is bezng required of as a part of the building permit approval for Gold Ea��e. Palic� Discussion We have discussed this tnat�er wit� �he building owner. H� is �ery interesied ita nr�oving forward with his additiQn and cloes not feel that we st�o�ld be applying tlae C�WMP polieies to his ad�ition since it is a pre- existing s�r�et�re. T--Ie has indicated that he has oniy e�perieneed fioading in the building once af�er the 19$7 super stort�€, which was an extreme rain even�, rain totals around �e City ranged frain 6 to 8 inches. Gattfiri�d Pit vvas e�panded in �he 1990's, and �is buildin� has not been �Iooded since. He is asicing t�at we allovv tk�em to rr�ove forward with the addition and is willing �o indeznzzi�'y the City shoulcl a rain eve�nt accur t�at ca€zses the street �oocEing �o c�a�age any portio�z of h�s bui�aing or private property. The City Attorriey has ceviewed t�e applicable city codes regarding the CSWMP policies. He has advised staff that deviation from thes� �olicies does na� iall �ant�er t�te usual variance pracedures, City Cade 1016.26B2 simply states that the City Engineer shall ce�i�y that a proposed plan is in cor�piiance witl� tk�e City°s CS WM�'. Secause o�the freeboard policies, I do not �'eel �I�a� � can do this wit�tout ia-nplementin� policy 1.8. As described abave, Policy 1.8 allows that when flood proteatio� is not passible we should develap an e�nergency response plan. Due to the potential liability to the City as tk�e result of �aod darnage to the new structure and other private property, staff �elt t�at this issue sho�ld be brought to the City Council for discussion. Financial Impiicatians If the owner inde�nnifies the City fram any darnages to his �roperty due to floading in this s�bwaters�ed, �ere should t�e no fuiuc•e fir�a�icial irt�plications for the City.