A polyethylene composition having increased environmental stress crack resistance comprises a polymer blend of a multimodal high density polyethylene (HDPE) and an additive of at least one of a polycarbonate-siloxane copolymer, a polyethylene glycol (PEG) having an average molecular weight (Mw) of at least 2000, and a random block copolymer comprising two different saturated alkane blocks between two aromatic hydrocarbon blocks. The additive is present in the polymer blend in an amount of from 1 wt. % or less by weight of the polymer blend.