ad

下水モニタリング×生態学×機械学習:老朽下水道インフラを予防保全 ―腐食リスクを細菌データから予測し、陥没事故の未然防止へ―

ad

2026-10-01 東北大学

下水道管の腐食による道路陥没などを未然に防ぐため、東北大学の研究グループは、下水中の細菌データと生態学の「種分布モデリング(SDM)」、機械学習を組み合わせた新たな予防保全手法を開発した。腐食に関与する硫酸還元細菌の生息適性を下水道管路網全体で推定し、管齢や管径などの既存データと統合することで腐食リスクを予測。高リスクと判定された上位約29%の管路を点検対象とした場合、実際の重度腐食箇所46カ所のうち41カ所(約89%)を発見できた。下水モニタリングと生態学的解析をインフラ維持管理に応用することで、点検の優先順位付けを高度化し、老朽下水道の効率的な予防保全につながることが期待される。

下水モニタリング×生態学×機械学習:老朽下水道インフラを予防保全 ―腐食リスクを細菌データから予測し、陥没事故の未然防止へ―

図1.下水モニタリングと種分布モデリングの組み合わせによる下水道管路腐食予測ワークフロー

<関連情報>

廃水環境DNAに基づく硫酸還元細菌のマッピングによる、種分布モデリングを用いたネットワーク規模の下水道腐食スクリーニング Wastewater environmental DNA-based mapping of sulfate-reducing bacteria for network-scale sewer corrosion screening using species distribution modeling

Junming Zhang, Kanki Watanabe, Wakana Oishi, Daijiro Mizutani, Mohan Amarasiri, Daisuke Sano

Journal of Environmental Management  Available online: 24 September 2026

DOI:https://doi.org/10.1016/j.jenvman.2026.131005

Highlights

  • Literature screening and qPCR identified SRB targets.
  • Species distribution models predicted SRB habitat potential.
  • SDM-derived SRB habitat improved RF prediction of sewer deterioration.
  • Microbe-informed framework supports targeted sewer pipe inspection prioritization.

Abstract

The deterioration of extensive underground sewer networks presents a critical global challenge, as traditional inspection methods are difficult to scale under resource constraints. This study evaluates whether wastewater environmental DNA (eDNA)-derived habitat potentials of sulfate-reducing bacteria (SRB) can provide additional predictive information for network-scale sewer corrosion screening. We applied a species distribution modeling (SDM) framework to three targets: the two literature-selected and locally detected SRB genera, Desulfovibrio spp., Desulfobulbus spp., and the functional gene dsrB, using wastewater samples collected across the predefined target network over two years, achieving an optimal Area Under the Receiver Operating Characteristic Curve (ROC-AUC) of 0.925 for Desulfobulbus spp. Given the established role of SRB in sewer sulfide production, the SDM-derived habitat potentials were subsequently used to train a machine learning model to classify pipeline corrosion status defined by the municipal CCTV assessment. Using the two-year mean habitat potentials, a Random Forest (RF) model achieved the highest test-set Area Under the Precision-Recall Curve (PR-AUC) of 0.670. For the selected RF model, test-set permutation importance, measured as the decrease in PR-AUC after feature permutation, was highest for pipe age. Among the microbial predictors, the SDM-derived habitat-potential features for Desulfobulbus spp. and dsrB showed comparable importance, followed by that for Desulfovibrio spp. These findings demonstrate a scalable, data-driven framework for sewer corrosion screening and support inspection prioritization across unsampled pipe spans within the investigated target network.

1002下水道
ad
ad
Follow
ad
ad
タイトルとURLをコピーしました