Watershed Modeling & TMDL

Watershed Modeling - Inflow/Outflow including TMDL, BASIN, BATHTUB, FLUX, MNLEAP & TMDL

A watershed is the land that receives precipitation that will eventually run into your lake.  What is on a watershed, whether that t is agriculture, animal feedlots, prairie, forest, paved roads, or bare soil can greatly influence how much nutrient gets into the lake and thereby how healthy the lake might be.  

To determine how much nutrient ends up in the lake, we can measure the inflowing water concentrations and the outflowing concentrations but these will not always be the same through a year.  Watershed modeling allows us on average to determine how much nutrients can get into a lake by considering the land type, the slope and shape of the water basin, the permeability of the soil and more.  The MPCA and many other governmental groups regulate how much nutrients get into water bodies and give dictums called total maximum daily load (TMDL’s) to set those amounts.  This is as the term seems to indicate the total amount of a nutrient that is allowed into a water body over a daily period.  Watershed modeling creates a simulation of flows based on precipitation and then can simulate how changes to the landscape or how using different management strategies can reduce nutrient inflow if it is greater than the TMDL.  

Some of the more population modeling approaches to doing these types of simulations include:

  • FLUX 

As part of the WRAPs program implemented by the MPCA watersheds are mandated to come up with water plans and do a TMDL assessment.  Let us help you with this. Contact us for your initial consultation which is always free and discover for yourself the Limnopro Advantage.


Discover for yourself the Limnopro Advantage!