PENGEMBANGAN DECISION SUPPORT SYSTEM BERBASIS AHP UNTUK PENENTUAN BOBOT KRITERIA DALAM PEMETAAN SPASIAL KERAWANAN BANJIR

Abstract

Flood vulnerability mapping based on Multi-Criteria Evaluation (MCE) requires a mechanism for weighting spatial variables that is transparent, consistent, and scientifically accountable. The Analytical Hierarchy Process (AHP) has proven to meet these demands; however, its implementation in field research still relies on unintegrated manual procedures that are prone to computational errors and lack structured audit trails. This study develops a web-based Decision Support System (DSS) using PHP 8.x and MySQL 8.x, designed specifically for the domain of criteria weight determination in spatial flood vulnerability mapping. The system was developed following a waterfall software engineering cycle that produces verifiable artifacts at each stage: a requirement document with eight functional requirements, a two-actor use case diagram, a nine-table database schema, and a two-stage testing protocol. Validation was conducted on a case study of the Ciliwung River riparian zone, Jakarta, involving four vulnerability variables and three experts from hydrology, spatial planning, and architecture. Functional testing results show that all eight core system functions passed without failure. All three experts produced assessments with Consistency Ratio (CR) values between 0.0075 and 0.0254, all consistent. The combined weights obtained through geometric mean are: distance to river (55.4%), elevation (28.0%), slope (9.1%), and land use (7.6%). Mathematical validation showed zero deviation between system output and manual calculations at four decimal precision. The main contributions of this study are: a domain-specific DSS requirement framework for flood vulnerability AHP that can be adopted in other geographic contexts, a three-tier architecture that separates AHP business logic from the interface and database, and a structured testing protocol encompassing black-box testing and mathematical validation.

Keywords: decision support system; Analytical Hierarchy Process; flood vulnerability mapping; software engineering; weighted overlay; PHP; MySQL; consistency ratio