20070404 Creek Rd Mixed Use Project 11042008 Hey, on that 24 rainfall distribution numbers. It appears that the
Christenson project used:
100 yr 24 hr rainfall = 6.15"
6 mo 24 hr rainfall (treatment flow) = 1.79"
It is almost imposible to get a value off the Isopluvial maps
provided within the manual. This values are also consistent with the
Thurston Co. requirements. Can you verify with some other reports, or
standard practice within Yelm if these are the acceptable values?
I would also like to note, that as we discussed I beleive the
correction factor based on impervious surfacing is not applicable to
infiltration facility BMP's. Due to the fact that the runoff is not
contributing to surface flows. Can you verify that information as well
and shoot me back an email.
Thanks again.
Jamey Barr
Project Engineer
Sound Engineering, Inc.
1102 Commerce St., Suite 300
Tacoma, WA 98402
Ph. (253)-573-0040
Fax (253)-573-0142