This study aims to examine how increasing suburban development has affected TSL.  The authors did a comprehensive study examining water chemistry, benthos, plankton, bacteria and productivity of the lake and compared it to previous data.  The authors note that most inputs to TSL come from 3 intermittent inflows (which they call East A, East B, and South). 

Bridgeman et al. found that chloride and conductivity have increased nearly 13x from 1981 to 1988 and has increased slightly since then.  Most of the chloride input probably comes from dissolved road salt flowing through the East B and South inflows.  Previous research had shown that the lake mixed thoroughly in November, 1927-1928 and 1939-1942.  However, in Nov. 1992, there was little mixing and the bottom of the lake was poorly oxygenated (<4 mg/l).  The authors suggest that most salt enters the lake in pulses (during storms) and that their residence time in TSL is probably fairly high.  Bridgeman et al. suggest that this increase in chloride concentration has resulted in higher lake stability, preventing complete fall and spring turnovers and consequently decreasing the oxygenation of deeper areas.  The authors suggest that stability has increased 63% compared to 1981 lake conditions. 

The authors found that there was a decrease in both abundance and diversity of all major benthic invertebrates between 1928 and 1999.  Chaoborus, chironomids and oligochaetes all shifted the spatial distribution of their populations to occur in greater frequency in shallower areas and less frequently occupy depths > 10m.  Sphaerid mollusks, despite being common in 1928 were only found once (n=1) in 1999.  In 1928, 12 species of offshore benthic invertebreate species were found, while only 4-5 species were found in 1999. 

Bridgeman et al. found that the phytoplankton community was dominated by Oscillatoria prolifica and O. limnothrix.  Diatoms and dinoflagellates were also found.  Bacterial abundance decreased  with depth for 5 meters and then increased below 5m.  Both before and after ice-out, respiration was the dominant ecological process, although the difference was less after ice-out.  The authors suggest that the absence of vertical mixing after ice-out may contribute to the low primary productivity rates since nutrients from the deeper hypolimnion are not supplied to the epilimnion zone. 

Although the fish community (not studied by the authors) has not appeared to change significantly, this study does show that the biology, chemistry and physical processes of TSL have been altered quite a bit and the authors give a convincing account that most of these changes are a result of development and increasing salt usage. 

Overall literature significance: Cited by 3, most recently in: Nancy E. Karraker, James P. Gibbs, James R. Vonesh (2008) IMPACTS OF ROAD DEICING SALT ON THE DEMOGRAPHY OF VERNAL POOL-BREEDING AMPHIBIANS. Ecological Applications: Vol. 18, No. 3, pp. 724-734.