Name:   Shortbus - Subject:   Water Rise - History of January Draw Downs Date:   12/29/2015 10:52:25 AM (updated 12/29/2015 11:13:59 AM)

So how long does it take to dump the lake volume thru the dam?

Generation is 23,674 acre foot/day.

Martin dam has 20 spillway gates that are 30 feet by 16 feet in dimension. The gates are opened as needed in the following sequence: 5-11-3-9-7-1-10-6-12-8-4-2-20-19-18-17-16-15-13-14 (left to right in the picture). The first 12 gates opened are above the basin. The capacity of each gate is 3,016,000 gallons per minute (6,700 cfs).

3016000 gallon   13328.2828282828 acre foot
-------------- = --------------------------    for each spillway.  20 spillways is 266560 acre foot per day
    minute                  day            
            (volume flow rate)   


20 spillways + generation is     290234 acre feet per day.  This is a wide open dam.

The lake has a surface area of 39,000 acres and a volume of 1,622,000 acre feet.

So it would take 5.6 days to dump the full lake.

The rain we had added 7 feet of 53 meters ( 160 feet).

So maybe it takes 7/160 * 5.6 days   or    .245 days to dump the rain we had at full dump.

Of course this assumes nothing flowing into the lake and the lake is square.