Corrosion of Zinc-Coated Steel in Selected Natural Fresh Waters

Location and water Type of zinc Years Agitation Corrosion rate (mm/year)
Gatun Lake, Canal Zone Tropical fresh water Intermediate 4 Stagnant 13
Gatun Lake, Canal Zone Tropical fresh water Intermediate 8 Stagnant 10
Pedro Miguel locks, Panama Fresh water Special high grade 5   18
Pedro Miguel locks, Panama Fresh water High grade 5   13
Pedro Miguel locks, Panama Fresh water Intermediate 5   11
Pedro Miguel locks, Panama Fresh water Select 5   14
Pedro Miguel locks, Panama Fresh water Prime Western 5   13
Ampari River, Brazil Fresh water   0.4 2.8 ft/s flow 137
Ampari River, Brazil Fresh water   0.45 2.2 ft/s flow 198
Source:  Porter, F. C.  Corrosion Resistance of Zinc and Zinc Alloys. Dekker, New York, 523pp.  1994.

Corrosion of Zinc and Zinc-Coated Steel in Sea Water

Location and water Type of zinc Type of test Years Agitation Corrosion rate (mm/year)
Eastport, Maine Seawater 99.1% zinc Mean tide level 3   25
Eastport, Maine Seawater 99.1% zinc Immersion 3   16
Bristol Channel Seawater Prime Western Immersion about 93% of time 4   91
Bristol Channel Seawater Galvanzied bar Immersion about 93% of time 4   64
Southhampton docks Seawater Prime western At half-tide level 3   13
Southhampton docks Seawater High grade At half-tide level 3   14
Southhampton docks Seawater Galvanized plate Immersion 1   28
Fort Amador, Canal Zone Tropical, Pacific Ocean Intermediate Immersion 4 0.15 m/s flow 20
Fort Amador, Canal Zone Tropical, Pacific Ocean Intermediate Immersion 8 0.15 m/s flow 16
Fort Amador, Canal Zone Tropical, Pacific Ocean Intermediate Mean tide level 4 0.15 m/s flow 23
Fort Amador, Canal Zone Tropical, Pacific Ocean Intermediate Mean tide 8 0.15 m/s flow 14
Panama Seawater Cast-Prime Western Immersion 1   25
Panama Seawater Cast-Special high grade Immersion 1   25
Kure Beach, North Carolina Seawater Special high grade Immersion 0.5 Flowing 48
Kure Beach, North Carolina Seawater Special high grade Immersion 4 Flowing 20
Kure Beach, North Carolina Seawater Brass special Immersion 0.5 Flowing 48
Kure Beach, North Carolina Seawater Brass special Immersion 4 Flowing 18
Kure Beach, North Carolina Seawater Galvanized Immersion 0.5 Flowing 48
Kure Beach, North Carolina Seawater Galvanized Immersion 1 Flowing 23
Kure Beach, North Carolina Seawater Galvanized Immersion 3.5 Flowing 15
Kure Beach, North Carolina Seawater Galvanized Immersion 5 Flowing 13
Gosport and Emsworth Seawater Hot-dipped Immersion 6 Flowing 9
Gosport and Emsworth Seawater Hot-dipped Immersion 6 Flowing 9
Gosport and Emsworth Seawater Cyanide, electrodeposit Immersion 6 Flowing 8
Gosport and Emsworth Seawater Sprayed, molten metal pistol Immersion 6 Flowing 4
Gosport and Emsworth Seawater Sprayed, powder pistol Immersion 6 Flowing 17
Gosport and Emsworth Seawater Sprayed, wire pistol Immersion 6 Flowing 6
Source:  Porter, F. C.  Corrosion Resistance of Zinc and Zinc Alloys. Dekker, New York, 523pp.  1994.

Corrosion of Zinc and Zinc Coatings Immersed in Various Industrial and Domestic Waters

Type of water

Corrosion Rate (mm/yr)

Mine water, pH 8.3, 100 ppm hardness, aerated 31
Mine water, 160 ppm hardness, aerated 30
Mine water, 110 ppm hardness, aerated 46
Demineralized water 137
River water, moderate soft 61
River water, treated by chlorination and copper sulfate 64
Tap water, pH 5.6, 170 ppm hardness, aerated 142
Spray cooling water, chromate treated, aerated 15
Hard water 16
Soft water 15
Sources: Defrancq, J. N. ; Zinc and zinc-lead alloys in domestic water, Br. Corros. J. 17, 125-130, 1982.
Slunder, C. J., and Boyd, W. K.; Zinc: Its Corrosion Resistance, 2nd ed., International Lead Zinc Research Organization, Inc., New York, 1986.