20080680 Ver 1_Staff Comments_20081209

08-0860 Savannah's Garden SD, Take 4
AML comments
December 9, 2008
The DWQ remains unconvinced that Drainage Area 4 is low density. Based on
the topography, the open space to the left of the swale that serves Drainage Area 4
is not part of the drainage area and therefore it is not appropriate to include it in
impervious surface calculations. Once that open space is removed from Drainage
Area 4, then it will clearly be greater than 24% impervious and will require a
stormwater management plan.
If you wish to retain the currently proposed site plan, then an appropriately
selected and designed BMP must be provided to treat the stormwater from
Drainage Area 4. Please provide a completed BMP Supplement Form with all
required items (see http://h2o.elu-.state.ne.its/sti/bmp forms.htm.
2. The only possibility that the DWQ can identify of keeping Drainage Area 4 below
24% impervious by taking ALL THREE of the following steps:
1. Permanently protecting the open space north of lots 9-13,
2. Permanently protecting the open space across from lots 25-26, AND
3. Permanently abandoning plans to develop lots 14-17, 19 and 42.
If you are interested in pursing the low density option, then please provide
calculations for the above conditions in order for the DWQ to determine whether
or not low density criteria has been met.