Research Projects

Cason & Associates conducts original research in support of aquatic resource management. Featured below are current research projects.

Selective Eurasian watermilfoil control

Effects of granular 2,4-D BEE herbicide on native and exotic plants in Wisconsin lakes.
Chad Cason¹

Abstract:

A total of 29 pre- and post treatment plant frequency data sets were analyzed from 14 Wisconsin lakes treated with granular 2,4-D BEE (2,4-dichlorophenoxyacetic acid - butoxyethyl ester) herbicide for the control of Eurasian watermilfoil (Myriophyllum spicatum L.). The application rates of granular 2,4-D BBE were 112 and 168 kg/ha. Analysis of pre-and post-treatment changes in percent frequency for 41 species of aquatic plants indicated Eurasian watermilfoil was the only species to show significant declines in all the surveys (averaging -65.0% at 112 kg/ha, and -84.2% at 168 kg/ha.). Northern watermilfoil underwent declines in frequency at the highest 2,4-D application rate (-82.6%) but showed an increase (8.8%) at the lowest rate. This high degree of selectivity of 2,4-D BEE against Eurasian watermilfoil suggests that this herbicide is an important tool for restoring plant communities that have been degraded by Eurasian watermilfoil.

Key Words:

Eurasian watermilfoil, butoxyethyl ester, species, exotic aquatic plants

Click here to view complete document in pdf format.

Impacts of Aeration on Effluent TSS in Stormwater Ponds: A Literature Review

- DRAFT -

Chad Cason
January 31, 2007

Introduction

World wide, aeration is perhaps the most widely used tool for managing aquatic systems. Aeration is most commonly used for treatment of wastewater (EPA, 1989), improvement of fisheries, mosquito control, ice management, reduction of nutrient loading, sediment management, improvement of water clarity and control of algae. Stormwater detention ponds are created primarily to act as settling basins for urban stormwater runoff. These detention ponds have been shown to reduce effluent, nutrients, chemical oxygen demand and heavy metals. Their primary function though, is to reduce effluent total suspended solids (TSS) (Prey, 1994).

Wet detention basins tend to be shallow (3-7 feet) and fertile due to high nutrient loading. Therefore they are prone to noxious algae blooms. They also tend to be stagnant and anoxic due to a small surface to volume ratio. These conditions discourage fish life and encourage production of insects, such as mosquitoes. Many stormwater ponds are located in residential areas where these factors produce health concerns, reduce aesthetics and depress real estate values. As a result, many municipalities, homeowners, neighborhood associations and real estate developers have employed aeration technology in order to mitigate the negative aspects of stormwater ponds.

This report attempts to explore the potential impacts of aeration on the primary function of stormwater ponds: reduction of effluent TSS.