Portsmouth, New Hampshire: water and wastewater capital improvement projects
11 line items · $74M · starting 2026–2027 · 1 plan
Portsmouth's published capital plans list 11 water, sewer and wastewater line items with a combined planning budget of $74M, of which 6 items worth $55M sit in the wastewater and sewer departments. The largest single item is Mechanic Street Pumping Station Upgrade at $26M (2025–2031). The ten largest items are listed below; the full list with descriptions and page references is in Klarifi.
A capital improvement plan (CIP) is a city’s multi-year budget for building and replacing infrastructure. The water, sewer and wastewater sections list each project with its budget and the years it is funded, which makes them the earliest public signal that a plant, pump station or pipe network is about to be upgraded, usually two to four years before a contract is awarded.
The largest water and sewer projects in Portsmouth
| # | Project | Department | Type | Budget | Years |
|---|---|---|---|---|---|
| 1 | Mechanic Street Pumping Station Upgrade | Wastewater | Pump stations | $26M | 2025–2031 |
| 2 | Annual Water Line Replacement | Water Distribution | Water mains and distribution | $10M | 2026–2031 |
| 3 | Annual Sewer Line Replacement | Wastewater | Sewer rehabilitation and I&I | $9M | 2026–2031 |
| 4 | Wastewater Reuse at Pease Wastewater Treatment Facility | Wastewater | Wastewater treatment plant upgrades | $8M | 2027–2031 |
| 5 | Peirce Island Wastewater Treatment Facility | Wastewater | Wastewater treatment plant upgrades | $5M | 2025–2027 |
| 6 | Water Storage Tanks Improvements | Water Supply | Storage tanks and reservoirs | $5M | 2025–2031 |
| 7 | Wastewater Pumping Station Improvements | Wastewater | Pump stations | $4M | 2025–2031 |
| 8 | Sewer Service Funding For Sagamore Avenue Area Sewer Extension | Wastewater | Sewer rehabilitation and I&I | $3M | 2025–2031 |
| 9 | Well Stations Improvements | Water Supply | Wells and groundwater | $2M | 2026–2031 |
| 10 | Reservoir Management | Water Supply | Storage tanks and reservoirs | $2M | 2026–2031 |
1 more line items in Portsmouth, with descriptions and contacts
Klarifi holds every Portsmouth line item with its description, the page it appears on and the source document, plus 38 verified contacts at the city’s treatment plants. Track new plans as they are adopted and compare with similar projects in other cities.
Planned spend by start year
Before 2026
$43M
6 items
2026
$23M
4 items
2027
$8M
1 items
By department
| Department | Line items | Budget | Share |
|---|---|---|---|
| Wastewater | 6 | $55M | 74% |
| Water Supply | 4 | $9M | 12% |
| Water Distribution | 1 | $10M | 13% |
Project types in Portsmouth's plan
Wastewater treatment plants in Portsmouth
2 publicly owned treatment plants in Portsmouth with 112 permit violations in the last three years. Each profile shows flow, permit, technology and compliance data.
| Plant | Avg flow (MGD) | NPDES | Violations (3y) |
|---|---|---|---|
| Pierce Island Wastewater Treatment Plant | 2.38 | NH0100234 | 47 |
| Pease Wastewater Treatment Facility | — | NHG58A007 | 65 |
Other New Hampshire cities with capital plans
Portsmouth capital plan questions
Sources and methodology
Budgets and years are as published in Portsmouth’s capital improvement plan or adopted budget. Klarifi extracts the water, sewer and wastewater line items from the published document, keeps the page reference for each one, and assigns a project type from the title and description with a keyword classifier. Figures are planning budgets, not awarded contracts, and can change when a plan is re-adopted.
Documents: CIP 2025–2030 (11 line items).
Data refreshed September 11, 2026.