Local government leaders in Nashville are considering a proposal to transform the municipal wastewater treatment system into a significant stream of clean energy and recurring city revenue. Under a legislative plan before the Metro Nashville Council, municipal sewage byproducts that are currently burned off into the atmosphere would instead be captured, purified into renewable natural gas, and distributed into commercial energy pipelines.
The proposal hinges on a pair of legal and operational agreements between Metro Water Services and Burnham, an infrastructure development firm headquartered in Arlington, Virginia. City officials anticipate that the public-private partnership will allow the metropolitan government to modernize its utility infrastructure while generating millions of dollars in net gains without requiring local taxpayers to fund the facility's construction.
Legislative progress on the initiative is already underway in the Davidson County government. The measure authorizing the underlying gas rights and property lease agreements formally cleared its second reading before the Metro Council on Sept. 15. However, the proposal must secure one additional affirmative vote during a final council reading before the partnership can be officially executed.
If final approval is granted, the project will be centered around Metro Water Services' existing biosolids installation located at 1810 Cement Plant Road in Nashville's Germantown area. The planned renewable natural gas plant will take the raw biogas produced at that location and refine it so that the finished fuel meets the specifications required to be injected directly into a nearby natural gas transmission line.
Under the negotiated framework, Burnham will carry full responsibility for the financing, design, engineering, construction, ownership, and long-term operation of the new processing facility. This operational structure insulates the municipality from the upfront capital costs and technical liabilities associated with building complex clean energy infrastructure.
In return for supplying the raw biogas feedstock from its wastewater operations, the metropolitan government will receive substantial financial compensation. A fiscal analysis prepared for council members indicates that Burnham will distribute quarterly royalty payments to the city, calculated at 70% of the net revenue generated from selling the processed gas and its associated environmental attributes.
The financial pact guarantees that Metro Water Services will collect a minimum royalty baseline of $1 million per calendar year throughout the operational phase. Revenue totals could rise significantly above that threshold depending on market pricing and the volume of renewable natural gas sold into commercial distribution channels.
The accompanying property agreement designates an adjacent 1.2-acre municipal parcel at 1815 Cement Plant Road to house the new processing infrastructure. Under the lease terms, Burnham will pay Metro Water Services a nominal rent of $1 each year across the lifetime of the project.
Both the gas rights contract and the ground lease establish an initial operating term of 20 years. The agreements also include provisions allowing for two successive five-year contract extensions, provided that both the municipal utility and the private developer mutually agree to continue the partnership.
Following final legislative authorization, the project will move through an estimated two-year development schedule before entering full commercial service. The terms require Burnham to break ground on construction within 18 months of the agreement's effective date and achieve full operational readiness six months after construction begins.
The underlying process relies on the natural transformation of municipal wastewater. Incoming wastewater contains a mixture of liquid effluent, human waste, discarded food scraps, household oils, and assorted chemical compounds. During treatment, the liquid stream is separated from the solid materials, which are then treated to create nutrient-dense biosolid products that meet Environmental Protection Agency standards for agricultural fertilization and soil conditioning.
A primary byproduct of this treatment process is biogas, which is created through anaerobic digestion—a natural biological mechanism where specialized bacteria break down organic waste in an oxygen-free environment. Metro Water Services currently produces an average of 1.5 million cubic feet of raw biogas every day at its Germantown facility.
At present, the vast majority of that daily biogas volume is simply flared off into the open air via waste gas burners. Building the specialized conversion facility will allow the city to achieve 100% beneficial reuse of the biogas generated at the biosolids site, eliminating waste while producing pipeline-grade fuel.
A critical component of the venture's financial model involves the generation of renewable energy credits. According to regulatory definitions from the U.S. Environmental Protection Agency, these credits are established when qualifying facilities generate and deliver one megawatt-hour of electricity to the power grid from renewable resources.
These tradable credits allow commercial buyers and consumers to differentiate green power from conventional fossil-fuel electricity flowing through the broader grid. Customers seeking to meet sustainability goals purchase the credits separately to verify that their power consumption is matched with clean generation.
By monetizing both the physical gas and the accompanying renewable credits, Nashville aims to establish a reliable source of municipal income. Should council members grant final approval in the coming weeks, the Germantown facility will begin its two-year transition from burning off wastewater emissions to generating clean energy and steady civic revenue.
(0)