Calcium Magnesium Acetate and Sodium Chloride, Two

Deicers , and their Effects on Water Quality

Eileen Field

Snow Hydrology, GEOG 5321

Deicing Technology

Deicing of roadways has been used as a means to create a safe environment for travel

Accident levels decrease after deicing

Sodium Chloride

Used as a deicer since the 1930’s

Has been known to be detrimental to water supplies

Stored in dome such as this to help prevent leakage

Calcium Magnesium Acetate

Currently sold by the Cryotech Deicing Technology Corporation

Sold in a pelletized version that is hydrated to form a CMA solution

Eutectic Points for Deicers

CMA and Sodium Chloride have different eutectic points

Eutectic point is the lowest possible melting temperature for a given mixture of materials

Corrosion

A problem with deicing technology is its ability to cause a corrosive reaction on metals to which it comes in contact

CMA is less corrosive than Sodium Chloride

Deicing Studies

The Effect of Calcium Magnesium Acetate (CMA) Deicing Material on the Water Quality of Bear Creek, Clackamas County, Oregon, 1999 By Tanner and Wood, Water Resources Investigation No. 00-4092

Environmental Monitoring and Evaluation of Calcium Magnesium Acetate (CMA) By Horner, National Research Council Report 305, Washington, D.C.

Deicing Studies (cont)

Effects of Calcium Magnesium Acetate, A Road Deicer, on the Lentic Environment In Interior Alaska; Rea and LaPerriere, 1985, Alaska Department of Transportation

A Method of Predicting Road Salt Runoff in New Hampshire; Spear and Schiffman, 1975, National Academy of Sciences, Washington, D.C.

Tanner and Wood Study

Assessed the effects of the addition of CMA into several ponds

The biochemical oxygen demand, measure of the quantity of oxygen consumed by microorganisms during the decomposition or organic matter, for this study is listed

BOD value By Day

8.8

8.9

9

9.1

9.2

9.3

9.4

0 5 10 15 20 25 30

DaysB

OD

Val

ue

BOD value

Horner Study

The effects of the addition of CMA to eight ponds was assessed

Percent of CMA exerted after five and twenty days is listed

Temperature By Percent Exerted

0

20

40

60

80

100

20 10 2

Temperature (Celsius)P

erce

nt

Exe

rted

Percent ExertedAfter 5 Days

Percent ExertedAfter 20 Days

Rea and LaPerriere Study

Calcium ion concentration was found for several ponds that were tested

Results are listed

Dissolved Calcium (Mg/L) By Date

2.32.42.52.62.72.82.9

1/14

/04

1/28

/04

2/11

/04

2/25

/04

3/10

/04

3/24

/04

DateD

isso

lved

Cal

ciu

m

(Mg

/L)

Dissolved Calcium(Mg/L)

Spear and Schiffman Study

Due to ionic pulse action within the snowpack, Sodium concentrations exceed levels suggested by the American Heart Association

Precipitation Amounts

Average Precipitation By Month

020406080

100120

Janu

ary

Mar

ch May

July

Septe

mbe

r

Novem

ber

Month

Av

era

ge

Pre

cip

ita

tio

n (

mm

)

Average Precipitation(mm)

Conclusion

Sodium Chloride does have negative environment impacts based on its ability to contaminate groundwater

Calcium Magnesium Acetate is a viable deicing alternative but it does cost as much as twenty times more than Sodium Chloride