Orleans advisory group says sewer hookups rising as treatment plant meets permit but work remains on nitrogen targets

The advisory body to the Select Board heard an update on sewer phase-two connections and recent wastewater treatment plant performance, with members urged to continue tracking data and consider incentives for the plant operator.

Mike (Wright Pierce), the engineer presenting a nitrogen-removal status report, said 19 properties are already connected and flowing to the treatment plant and that staff have received 71 hookup applications; he estimated about 45–46 properties are ready to proceed once paperwork is finalized. Tim Harrison (ACOM) noted seven new red dots on the project map and said the town is ‘‘seeing them coming online quickly.’’

Mike summarized recent plant performance for January–March: influent flows of roughly 70,000–80,000 gallons per day during that period (plant nominal annual-average capacity is 350,000 gpd), septage receipts between about 3,000 and 13,000 gpd, biochemical oxygen demand (BOD) values generally between 5 and 11 mg/L (permit limit 30 mg/L), and suspended solids (TSS) showing more variability with an outlier of 34 mg/L in February (permit limit 30 mg/L). He said average total nitrogen from the plant was near 5 mg/L and nitrate around 2 mg/L — markedly better than the board-of-health samples from many innovative alternative (IIA) systems in town.

On nitrogen-removal planning, Mike walked the group through a graphic showing watershed removal needs: Pleasant Bay at about 7,315 kg/year and other sensitive watersheds assigned targets (NSET ~5,000 kg/yr, Rock Harbor ~1,500 kg/yr). He said the first three sewer phases would remove roughly 7,000 kg/year versus an estimated townwide need near 14,000 kg/year, describing Orleans as ‘‘about halfway there’’ under current assumptions.

Committee members pressed on operational drivers. One member recommended an incentive/penalty structure in the operator contract to reward lower suspended solids and improved nitrogen removal; the presenter and others cited temperature and low winter flow as important factors that can degrade biological removal and suggested modest capital or operational adjustments (equalization, blowers, filter tuning) could improve outcomes.

The presenter noted a letter dated June 7 addressed to Drew Oay at "D." will be sent as an annual progress update; copies are going to the Pleasant Bay Alliance and the Cape Cod Commission, and the group discussed whether additional copies (noted in the transcript as "Eastan") should be shared because parts of the removal work relate to townwide objectives.

Members also discussed consumptive-use (water not returning to sewers) assumptions used for nitrogen-credit accounting: the rule-of-thumb 10% figure was 13% for Orleans in 2024 and 23% for a dry 2025 sample, prompting suggestions to expand sampling and add a phase-indicator field to the Sue Brown tabulations used for credits.

Tim gave a procurement update for phase three: bids have been opened, contract documents and bonds are under review, DP approval to award is pending, a notice to proceed is expected in July, and on-site construction activity is likely early–mid fall.

The advisory group agreed to continue tracking plant metrics, to share Veolia performance reports with the committee membership, and to ask staff (DPW) to explore contractor incentive options. No new formal policy was adopted; the committee recommended staff follow up with the DPW director and the plant operator on actionable steps.

The committee voted to approve the May 28 minutes and later moved and seconded adjournment.