Opinion: inappropriate applications of phosphorus loading models in lake management regulatory policy

Abstract

Lehman J. 2023. Opinion: inappropriate applications of phosphorus loading models in lake management regulatory policy. Lake Reserv Manage. 39:273–277.

Imposition of total maximum daily load (TMDL) regulations based on external loading has little or no effectiveness when nuisance conditions are caused almost entirely by internal loading. A case study example from southeastern Michigan illustrates how persistent application of flawed management theory fails to achieve water quality objectives. Observations reveal that nuisance blooms are nearly contemporaneous with polymictic episodic injections of anoxic, phosphorus-rich hypolimnetic water into surface waters. Even a 10-fold increase in external loading during the Great Northeast Blackout of 2003 failed to trigger a nuisance bloom.

Keywords:

• Cyanobacteria
• internal loading
• nonpoint sources
• nuisance blooms

Disclosure statement

No potential conflict of interest was reported by the author.