2006 headwater inflows to Park drawing to a close
SFL Weekly Watersheds Summary: Dec 4 – 10
RAINFALL. This year’s dry season started early (early October) and has remained relatively rainless District wide for the past 10 weeks. Its also shaping up to be a well-below average rainfall year for the District. All major basins of the SFWMD have received under 50 inches of rain over the past 365 days. The Lake and Kissimmee River valley have received under 35 inches over the past 365 days. To put that in comparison, the Big Cypress area has been averaging around 58 inches of rain per year over the past 5 years, whereas the Lake and Kissimmee Valley have been averaging 45 and 52 inches per year, respectively, over the past 5 years. Official totals won’t be in until we get through the New Year, but suffice it to say that 2006 is chiming in on the lower end of the yearly rainfall spectrum. What will be interesting is to see how and if the burgeoning El Nino condition factors into the winter rainfall picture come 2007.
BIG CYPRESS. Preserve-wide water levels are currently tracking at a new 5-year low for mid December. We are currently about 6 inches lower than December of last year, and about 4 inches lower than the 5-year December average. Water levels have dropped about 12 inches in the 10 weeks that past since summer water levels peaked at this year’s high water mark in the mesic pines in late September. Sheetflow spread across the entire preserve during that high water mark, lapping its wetting front up into the our miniature mesic pineland highlands, and flowing at over 4,000 cfs across US41. In comparison, 10 months later in mid December, only remnant patches of this year’s high-water sheetflow regime remain, and non of it is flowing other than some minor flows at a few untamed canals. Surface waters continue their retreat into the taller cypress, swamp forest, and marshes. A thin film of standing water is still holding on some of our wet prairies, but the majority of wet prairies have been reduced to a soggy marl, which, with continued drying, will soon begin to crunch to the footstep instead of splash.
EVERGLADES. Flows through S12s are coming to a close. The S12D and S333 are still flowing, at around 100 cfs each, but headwater flows into Everglades National Park have pretty much come to an end for the year until next summer. This year saw the lowest volume of water to move through the S12s since the drought year of 2000. Water depths in southern 3A are holding steady for the past 6 weeks at around a 2.5 ft depth. Central and northern 3A have dropped about 0.5 ft over the same 6-week time span to depths of around 2 and 1 ft, respectively. Water is currently pooling around 1.8 ft on the north side of the S12s, 2.2 ft behind the S11s, and over 3 ft behind the S10s.
LAKE O. Lake O is currently 4 ft lower today than it was 365 days ago in December 2005. Lake levels are currently 1.5 ft below the bottom of the lake’s interior-levee littoral zone. I’m assumming that would make most of that lake’s interior wetland habitat crunchy to the footstep other than in the trails that cut through it. Structural inflows from the lake have been very minimal to non-existent since the start of October. Minor outflows have occurred over the same time period, presumably for water supply and agricultural purposes and for keeping the saltwater wedge at bay in the lower Caloosahatchee. Lake level is currently 7.5 inches higher than mid-December of the 2000 drought year.