Sea water or Effluents: Piles exposed to seawater or to effluents with a pH much above 9.5 or below 4.0 will require painting (i.e., paint the pile, then construct the backfill) or encasement in concrete to resist corrosion. As an alternative to painting or concrete encasement, a splice that uses a slightly larger section in the corrosive zone may be made.
water line fluctuation Zone: In general for the several feet of zone of water line fluctuation along the pile the corrosion is also prominent requiring same treatment of painting or concrete encasement.
According to NBS studies on substructures like both sheet-pile and bearing-pile over 40 years if piles are driven in undisturbed natural soil deposits, pile corrosion is not great enough to affect the strength of the piles significantly. These studies covered soils with pH (a pH less than 7 is acidic) values from 2.3 to 8.6, and electric resistivities of 300 to 50 200 ohm • cm which was further concluded that as long as the soil was undisturbed, the soil characteristics and properties are not significant. For a given site soil ohm-cm (soil resistance) can be used to determine the probability of pile corrosion.