Wastewater System - Drumbo

The Drumbo Wastewater Treatment Plant (WWTP) provides wastewater treatment for residential, commercial, and industrial users in the Village of Drumbo.

The wastewater collection network transports waste to the WWTP for treatment. The wastewater collection network consists of a mix of gravity mains, and forcemains. Wastewater flows by gravity wherever possible, where changing elevations require the use of sewage pumping stations (SPS). Other specialized structures such as maintenance holes, valve vaults, meter stations, diversion structures and siphons are required to convey wastewater to the WWTP.

Inventory

The replacement cost valuation for the linear assets in this portfolio are based on current tender prices, where available. The replacement cost valuation for wastewater vertical is based on the latest information available, which includes current replacement costs, insurance valuations, inflation, and valuations from studies and assessments completed in prior years. The significant increase in replacement cost, and sanitary main inventory count stems from the completion of the Wastewater Treatment Plant Phase I expansion project in 2024.

Condition

The percentage of assets in poor or critical condition has decreased from 17% as reported in the 2024 AMP to 16%. The percentage of assets in good or excellent condition has increased from 63% as reported in the 2024 AMP to 76%. As assets continue to age their condition rating will decline until lifecycle strategies are triggered and completed.

Key Performance

It is intended that all wastewater assets will be maintained, rehabilitated, and replaced to perform the same function and manage the same capacity as they are currently designed to do. To ensure levels of service are maintained, staff monitor impacts from changes to capacity demands to plan for changes to current practices and budget requirements.

Proposed Levels of Service Review

Information on the scenarios reviewed is contained within the AMP document. Based on the analysis, staff are recommending Scenario D. The proposed level of service target is to fund the system at 60% of overall lifecycle needs. The use of PVC pipes for linear started becoming popular in the 1970’s; their useful life of 90 years is theoretical as this material has not been in use long enough to confirm the lifespan. Staff also identified an improvement area in 2024, to look at the lifecycle strategies for process assets as it may be beneficial in the long-term to incorporate various strategies and not anticipate a run-to-failure strategy on some of these assets. Once incorporated this may result in reductions to the annual investment required, as such staff feel it is not prudent to target the fully funded scenario at this time. Staff will continue monitoring asset conditions and risks to ensure the proposed service level does not negatively impact on the overall health and safety of residents through the operations of this service.

Funding Gap Analysis

Planned Investment Level

An estimated inflationary rate is used in the table below as the inflation rate used for the 2026 Budget is based on the rate as of June 30, 2025. As the interest portion of debt obligations declines those funds are re-invested and are included in the planned investment level in the table below. An estimated capital contribution resulting from growth has been included in the table as growth is paramount to the long-term sustainability of the Drumbo wastewater system. As the Wastewater Treatment Plant Capacity expansion project was completed in 2024, developers are now able to undertake the required planning processes before obtaining building permits. Based on recent market fluctuations it is difficult to ascertain how quickly that growth may happen, and thus when the additional rate revenue will be available for use towards the system’s operating and capital requirements. Slow or delayed growth may require significant increases on rates for short-term sustainability.

Proposed Investment Change

In addition to the planned investment level changes, an increase in the contribution to the Wastewater – Drumbo reserve of approximately 2% is proposed for 2026 through 2035. Although this only amounts to approximately $1,000 in 2026, the result is an estimated $0.23 increase in the monthly fixed charge for the average residential user or $2.76 annually. As the Wastewater – Drumbo system currently has the highest fixed rates within Oxford County, it would not be prudent to propose a higher increase at this time. Given the uncertainty around growth levels, the impacts of growth and sustainability of the system will be closely monitored.

Comparison of required investment to proposed investment (millions)