Comparison of median concentrations 1991-2001

2002 Lake Water Quality Report

Comparison of median concentrations for chemical data in City of Orlando lakes from 1990-2002.

Parameter	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002

pH	7.6	7.7	7.7	7.4	7.6	7.6	7.8	7.7	7.4	7.8	7.87	7.91	7.83

Alkalinity (mg/l as CaCO3)	49	47	50	49	45	44	42	44	43	43	46	44.0	44.1

Total Phosphorus (mg/l)	0.041	0.043	0.047	0.049	0.048	0.047	0.045	0.047	0.042	0.035	0.034	0.034	0.034

Ortho Phosphorus (mg/l)	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.004	<0.004	0.002

Total Nitrogen (mg/l)	0.86	0.84	0.89	0.83	0.84	0.79	0.80	0.75	0.73	0.77	0.77	0.78	0.75

Ammonia (mg/l)	<0.03	<0.03	<0.03	<0.03	<0.03	<0.03	<0.03	<0.03	0.03	0.04	<0.03	<0.02	0.01

Nitrate Nitrogen (mg/l)	<0.02	<0.03	<0.03	<0.02	<0.02	<0.02	<0.02	<0.02	0.02	0.02	<0.02	<0.02	0.01

Nitrite Nitrogen (mg/l)	<0.02	<0.02	<0.02	<0.02	<0.005	<0.005	<0.005	<0.005	<0.005	0.010	<0.005	<0.005	0.003

Total Kjeldahal Nitrogen (mg/l)	0.8	0.81	0.87	0.83	0.82	0.76	0.77	0.74	0.62	0.75	0.76	0.77	0.79

Total Suspended Solids (mg/l)	5.5	5.3	7.2	6.6	7.0	7.0	6.5	5.9	4.7	5.9	5.0	4.5	3.5

Volatile Suspended Solids (mg/l)	4.3	4.3	5.0	6.2	6.0	6.0	5.3	4.5	4.3	5.6	4.5	4.0	3.5

Total Dissolved Solids (mg/l)	131	120	126	125	116	114	114	108	114	128	130	130	128

Chlorophyll-a (mg/m³)	16.2	19.5	20.8	26.5	25.0	23.0	21.1	19.8	21.6	21.2	16.4	17.3	15.8

Conductivity (umhos @ 25°C)	205	200	200	199	198	182	173	179	171	176	180	191	196

Secchi Depth (m)	1.1	1.1	1.1	1.1	1.1	1.1	1.1	1.2	1.2	1.2	1.1	1.0	1.0