LAKE OKEECHOBEE HAS 9 MAJOR WATERSHED AREAS - -

Mouseover watersheds for LAND-USE and P-LOAD:
Watershed areas of Lake Okeechobee	Upper Kissimmee Lower Kissimmee Fisheating Creek Taylor Creek/Nubbin Slough Lake Istokpoga Indian Prairie East Lake O. Basins West Lake O. Basins Everglades Agricultural Area (EAA) They all, some more, some less, channel urban and agricultural polution to the Lake. And YES, apart from Nitrogen and other kinds, the source of the main problem :

It originates primarily from urban wastwaters and agricultural activities in the Lake watershed :
.
About 5,600 tons of P is imported and applied in Lake Okeechobee watershed every year
- this is enough to meet Lake Okeechobee's TMDL (P goal) of ~105 t/y, for more than 53 years !
"Legacy" Phosphorus - an estimated 190,000 tons of P have already been deposited in the Lake
Okeechobee watershed - - this is enough to meet Lake Okeechobee's annual TMDL (P goal) of ~105 t/y,
for 1,800 years !
The Lake is receiving 656 tons of P per year (2009) < - - > 105 t/year is the recommended maximum.

The Lake just cannot cope with the P overload that keeps pouring in !
This is why the lake water is not welcomed anywhere - creating havoc in the estuaries where it curremtly goes
(via the Caloosahatchee and St. Lucie River) - let alone in P-sensitive Everglades located downstream.

Lake Okeechobee Watershed Statistics

Lowlying flat countryside - WET and DRY seasons		1-foot rainfall = 3 feet lake rise	Used by beef cattle ranching (pastures), dairy operations; vegetable, citrus, cane farming
Watershed Surface Area		3,062,000 ac. 4,785 sq miles	Water fed into the Lake	2 million acre-ft/y
Average LO Depth		9 feet	Maximum LO Depth	12 feet
Minimum LO Elevation		9 feet	Maximum LO Elev.	19 feet
81% of the phosphorus entering Lake Okeechobee comes from its northern watershed.
Over 90 %t of the total phosphorus entering the Lake from the north originates from Agricultural lands.
10% of the phosphorus entering the Lake comes from the southern Everglades Agricultural Area (EAA), which is dominated by sugarcane production. Since most of EAA lies below the level of LO this water is back-pumped, the practice currently largely discontinued. However, the legacy phosphorus from past years of routine back-pumping is still sitting in the Lake.
P import contribution	Improved pasture fertilizer	29 %	Dairy	22 %
	Truck crops	22 %	Citrus	9 %
	17 % of this fertilizer ends up as run-off in Lake Okeechobee
P run-off contribution	Improved pastures	58 %	Citrus production	9 %
			Dairy production	8 %

Watershed land use and Phosphorus

			Some land uses contribute high amounts of "loose" Phosphorus - it escapes into streams and canals feeding LO. E.g. check high P contributions from "Improved Pastures" (24.5%)", "Citrus" (18.1%), "Row Crops" (7.8%). Conversely, BIG "Natural Areas" contribute relatively little P !
LO watershed land use	P contribution from the LO watershed	P runoff

Phosphorus soil deposits

			The problem is with "legacy" phosphorus deposited in soil over the decades. It is present there in highly mobile forms that leach easily and run off with rain water.
Net Phosphorus imports - North LO watershed	Conceptual legacy P sources in soil	"Legacy-P" is greater than native P and in mobile forms that are easily released

Useful Links for information on Lake Okeechobee Watershed

REPORTS	WEBSITES
EvergladesHUB - Blog with Bo-	ACE-CERP website
Sludge Residuals Application - Audubon Report-090620	SFWMD - LO Watershed
Lake Okeechobee Lake Stage - CERP Performance, 2007	Florida Dept. Environ. Protection -LO Basin Status Reports
2007 South Florida Environmental Report (SFER, SFWMD)	EPA - Evaluation of Legacy Phosphorus in the Northern Lake Okeechobee Watershed (SFWMD)
Lake Okeechobee: A Synthesis of Information and Recommendations for its Restoration - Audubon 2005	Watershed Assessment Model (WAM)
Resources of Lake Okeechobee - Audubon, 2005	LakeOkeechobee.org: Phosphorus
BioOne-2005: LAKE OKEECHOBEE CONCEPTUAL ECOLOGICAL MODEL (by K.E.Havens & D.E. Gawlik)	LakeOkeechobee.org: Cattle ranching