When proposing a new development, the developer will be responsible for ensuring the sanitary sewer infrastructure has adequate capacity. If improvements are required, the developer will size the infrastructure to convey the existing flows, the proposed flows, and the future flows anticipated in the County Comprehensive Plan. In this instance, the developer is typically eligible for partial reimbursement through the County's Reimbursement Policy.
When the developer upgrades the existing sewer system to handle future wastewater in the County, they can usually get some of their money back through the County’s Reimbursement Policy.
| Policy | The Board of Supervisors adopted a revised policy in 2022 which guides the current reimbursement program. The policy can be found here. |
|---|---|
| Formula | A formula is used to figure out how much the County will reimburse. The reimbursement will partially cover costs for Design, Permits, and Construction costs. |
| When | The developer pays upfront but can be partially reimbursed during construction. The final reimbursement will come after the County accepts the new sewer system. |
| Planning | A separate Public Improvement (PI) Plan is required to help track costs. This follows the County’s normal review and permitting process. |
| Agreement | A Reimbursement Agreement must be signed after technical approval but before the Land Disturbance Permit is issued. |
| Work | The developer must get 3 bids for major construction work. The lowest bid is used to decide the reimbursement amount. |
The reimbursement program provides payment to developers who have upsized Fairfax County wastewater infrastructure. Developers are responsible for the planning, design, and construction of the sanitary sewer asset and must follow the typical County development process. At project completion, the County will reimburse the developer the proportional cost share of the project. The developer is responsible for the cost share associated with the flows from their development. The County is responsible for the cost share associated with the existing and future flows.
When areas redevelop, the existing sewer may not have the capacity to handle increased wastewater flow. Developers who are adding flow to sewers that are at capacity must upsize sewers to ensure the system can accommodate existing and future demand. Undersized sewers may result in sanitary sewer overflows which is a public health hazard.
Fairfax County staff review all development plans to determine the impact of the proposed development to the sanitary sewer system. If the additional flow from a development will exceed the capacity of a sanitary pipe, the development is responsible for upsizing that pipe. The new pipe must be sized to accommodate existing flow, the development flow, and all potential future flow. The developer is responsible for installing the pipe, and the pipe must be in operation prior to the development connecting to the County system. After project completion, the County will assume ownership and will be responsible for operation and maintenance of the sanitary sewer asset.
The pipe upsized by developers is designed to accommodate flows from both existing and future users. Therefore, the County’s portion of the reimbursement program is funded through existing and new users. The program is primarily funded by availability fees (tap fees) collected from new users, where “growth pays for growth.” New users pay for the right to add their flow to the sanitary sewer system. Existing users benefit because the new pipe guarantees a functional, brand-new pipe, and a small amount of the user fees are applied to help fund the program.
