19 Oct 2021

Reducing Infiltration & Inflow in a US utility

Baseform automatically generates indicators that the utility is using to tackle I&I.

 

Baseform is connected to all of the utility’s sewer system flowmonitoring, and dynamically detects and quantifies detailed I&I metrics, at system and catchment/subcatchment level, cross-checking results with water billing, pumping and others.

In its monthly I&I Task Force meetings, the utility focuses on specific sectors based on the I&I/LF indicators; if needed, additional monitoring is installed, and CCTV inspections are combined with direct repair and renewal.

Recently, one source of infiltration was found in a mains, which accounted for 3–4 MGD alone. Monitored volumes in Baseform indicate an overall infiltration flow of 34 MGD.

At a treatment cost of $1151/MGal, infiltration alone represents up to $14 million yearly in treatment costs. Combining monitoring, inspections and multi-criteria prioritization to guide direct O&M intervention and annual CIP, the utility estimates to be able to reduce this inefficiency by up to 50% in the coming 3-5 years.

Size of the problem: $14.2 M (annual treatment costs of I&I volumes).

Potential savings: $7.1 M (medium-term expected yearly reduction in I&I).