June 30, 1997
Fairbanks North Star Borough
P.O. Box 1267
Fairbanks, Alaska 99707

Atten:
Mayor Jim Sampson
F.N.S.B. Assembly Members
F.N.S.B. Planning Commission

RE: FUTURE FLOODING WITHIN THE FAIRBANKS NORTH STAR BOROUGH

Dear Fairbanks North Star Borough officials;

The Fairbanks chapters of the Alaska Society of Professional Engineers, American Society of Civil Engineers, Alaska Society of Professional Land Surveyors, and the Alaska Section of the American Water Resources Association, have recently joined together to represent Fairbanks professional engineering, surveying, and water resource community in recommending that additional action be taken to improve the existing protections and measures already implemented to minimize damage resulting from surface- and/or ground-water problems in recent years; including the Badger Road area, lands immediately down-gradient from the Moose Creek Dam and Spillway, Steamboat Landing Subdivision, the Rosie Creek/Perkins Drive area, and properties near Noyes Slough and other natural drainage features. In each case it has now been known for many years that surface-water flooding and/or high ground-water levels present problems for development.

With money for flood control and area-wide drainage projects becoming increasingly more difficult to obtain, we believe that it is time for the Fairbanks North Star Borough (FNSB), aided by the appropriate state and federal agencies, to implement the actions which will more completely limit the potential for future flood damage in the Borough. Specifically, we recommend that the following actions be taken.

1. High Ground Water: The FNSB should identify and designate ground-water hazard zones on FNSB's flood insurance maps. (For the purposes of this letter, a ground-water hazard area is one where ground-water comes close enough to the surface of the land at time intervals frequent enough to negatively impact proposed or existing development.) Appropriate stipulations addressing construction within such ground-water hazard zones should be added to FNSB's Title 15, Building and Construction in Flood Hazard Areas, so that compliance would be mandatory and consistent. With information presently available, a ground-water base map could be prepared which defines these ground-water-water base elevations. The new ordinance(s) should reference this ground-water base map and specify a separation distance between the elevations shown on the ground-water base map and the bottom elevation of septic systems and each building's first finished floor. Areas which are presently known to have ground-water hazards include the area bounded by Badger Road and the Richardson Highway, and the area immediately down-gradient from the Moose Creek Dam and Spillway.

2. Surface-Water Flooding: The FNSB should change the flood-zone designation for the area bounded by Badger Road and the Richardson Highway from Flood Zone X to Flood Zone AO. This would require the first finished floor elevation on new structure construction to be at least 2 feet above the surrounding ground. Additionally, FNSB should amend Title 15 to regulate development in Flood Zone AO, and to make the ordinances applicable to basement construction in Flood Zone AO consistent with those which currently deal with Flood Zone AE.

3. Runoff Control: The FNSB should have area-wide drainage plans prepared to evaluate how future land development will impact runoff and affect downstream properties and watercourses. The FNSB should also amend Title 17 to require that those subdivision developments which modify the runoff characteristics of known flood-prone areas must design and install drainage facilities to assure that subsequent foreseeable private lot improvements will not result in an areawide 10-year flood peak discharge which is greater than would have occurred if the land had been left undeveloped.

We believe that, once adopted, the above three recommendations would better assure the limitation of inappropriate construction and subsequent water damage within flood-hazard areas. These actions should help the Borough to meet their responsibility for flood management and limit overall taxpayer liability in accomplishing this difficult administrative role. We would like to discuss our technical concerns and suggestions with you, and will be contacting you soon to arrange for a meeting to more thoroughly present these ideas.

Thank you for your thoughtful consideration of this matter.

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