Public infrastructure projects require consistent quality monitoring to ensure that construction outputs comply with technical standards, safety requirements, and government regulations. However, variations in implementation practices and compliance monito ring continue to affect project quality in local construction projects. In response, this study aimed to assess the existing QA strategies and practices applied in horizontal infrastructure projects and to identify the challenges encountered in their implementation. Specifically, the study sought to determine the respondents’ profile in terms of age, gender, position and length of service; assess the extent of implementation of QA strategies and practices; identify the challenges encountered in QA implementation; determine significant differences in QA strategies when grouped according to profile variables; and propose an enhanced QA mechanism for project monitoring. Additionally, the study employed a descriptive quantitative research design to gather and analyze data from 47 engineers and 33 contractors directly involved in DPWH projects. Data collection was conducted using a structured and validated researcher – made survey questionnaire based on DPWH guidelines and ISO issuances. Data analysis involved frequency count and percentage, mean, and Kruskal – Wallis test. Findings revealed that majority of the respondents were middle – aged , male , project engineers with 11 – 20 years of experience . It was further revealed that quality assurance strategies in horizontal projects was effectively implement, including briefing, selection of projects for inspections, checking of project documents, actual inspection, exit dialogue, inspection and assessment reporting, and monitoring corrective actions. Also, the best practices , such as management responsibility, quality planning, resource management, process control, auditing, quality recording, and data analysis and reporting , were well implemented, yet challenges like deviations from specifications, lack of accountability, and inconsistent quality standards persist. Furthermore, significant differences in QA strategies were observed based on age, position, and length of service. The study recommends strengthening DPWH – LGU coordination, institutionalizing structured QA protocols , and enhancing contractor accountability, while integrating AI – driven analytics in the proposed enhanced mechanism.

Keywords: quality assurance ( QA), horizontal infrastructure projects, DPWH guidelines, compliance monitoring, contractor accountability, AI- driven analytics