Abstract
<jats:title>Abstract</jats:title> <jats:p>High-density polyethylene (HDPE) has become increasingly used for subsea intake and outfall pipelines due to corrosion resistance, constructability, and cost advantages over metallic systems. Unlike steel pipelines, however, HDPE lacks a unified design framework for marine service, requiring designers to combine multiple thermoplastic pressure codes with offshore installation and stability methods. Existing practice remains installation-driven, with on-bottom stability and float-and-sink operations governing feasibility.</jats:p> <jats:p>This paper reviews available literature, summarizes current engineering practice, and proposes an integrated approach for wall thickness verification, on-bottom stability, and installation of HDPE subsea pipelines in shallow water. Key gaps are identified in standards, particularly in combined loading, empirical ballast methods, and mechanical interfaces. The results show that feasibility is governed by stability and operational control rather than strength-based criteria. Recommendations are offered to support the future development of unified design guidance for marine HDPE pipelines and to harmonize current installation-driven industry practice.</jats:p>