Rutherford County stormwater staff report education outreach, dye tracing results, 41 pond violation letters and ongoing enforcement

Rutherford County stormwater staff reported a year of increased outreach, fieldwork and enforcement at the Citizens Stormwater Advisory Committee meeting, highlighting dye traces in the Harpeth River and Compton Spring Basin, a large round of pond violation letters, and ongoing work to keep up with rising construction submittals.

"We did 15 activities this year, and we did 5 with our engineering and development community," said Jonathan, the county's stormwater coordinator, summarizing the program's public-education work. Staff said education events included Earth Day, farmers markets, a lawn-and-garden expo, Project WET activities in schools, a hazardous household waste event, and a litter cleanup program run with the Rutherford County Correctional Workhouse.

On fieldwork, staff reported four summer interns assist with pond inspections, municipal facility checks and stream assessments. "Every year we hire 4 summer interns, and they help us do a lot of our pond inspections," staff said. Inspectors reported 65 active construction sites in the county during the reporting period and that municipal operations and facilities inspections were completed.

Jonathan described dye tracing conducted in two rural watersheds. "We did, out towards the Eagleville, along State Highway 99, the Harpeth Head Of The River Spring," he said, reporting about four or five successful traces with straight-line distances of about 1 to 4 miles between injection and detection. Staff also performed traces near the Compton Spring basin (near State Highway 96 and Compton Road) and said they plan to publish a public map through the county GIS office that will show positive traces.

On enforcement and post-construction compliance, staff said the county issued two verbal warnings for suspected illicit discharges and used stop-work orders where construction started without permits. Sheila (staff member) said the county recently sent 41 pond or stormwater-control-measure (SCM) violation letters, primarily to homeowners associations. "We sent out, I believe it was 41, pond violation letters," Sheila said, adding many recipients have responded and some lacked prior education on maintenance expectations.

The county noted that the MS4 permit allows pond/SCM inspections on a five-year cycle, but staff said they completed all SCM inspections this year and are considering returning to annual inspections if resources allow. "We went this summer, we did them all," Sheila said. Inspectors use digital tools (Esri and Survey123) and an online checklist allowing photos and immediate reporting.

Monitoring and certification details: staff said no analytical monitoring was completed this year; an "Option 2" monitoring plan had been approved previously by the Tennessee Department of Environment and Conservation (TDEC), and several sites were removed from required sampling lists. The county is hiring an additional stormwater inspector and added engineers to meet increasing workload.

Proprietary treatment devices and low-impact development practices were discussed. Staff said long-term maintenance agreements for proprietary devices and other SCMs are recorded at the register of deeds to tie maintenance obligations to the parcel. One proprietary device installation was cited at a Farm Credit site near Old Nashville/Old Woodbury (John Bragg referenced). Staff described hydrodynamic separators and pervious pavers among technologies being installed; they said the county follows TDEC guidance and reviews vendor certifications such as Washington tape and NJDEP/NJCAT submissions where applicable.

Committee members raised a separate concern about fish-consumption advisories posted below Walter Hill Dam on the Stones River. A committee member noted signs advising against consuming fish and asked whether the county should pursue sampling or a grant. Staff responded that the county's MS4 permit requires monitoring only for certain pollutants (siltation and E. coli) and that state agencies and industrial permittees typically conduct other contaminant sampling. Staff said online state data indicated mercury contamination listings in that stretch of river and acknowledged they do not perform routine mercury sampling. Committee members asked staff to note grant opportunities and consider whether a county-led investigation or grant application would be appropriate.

Committee members asked staff to prepare additional outreach materials for proprietarily treated sites (pervious pavers, underground vaults) so property owners and managers understand maintenance needs and avoid actions that could damage system performance (for example, sealing permeable pavers). Staff agreed to send educational letters to owners of new or proprietary systems next year.

No formal actions were taken on the annual report during the public hearing; no public comments were submitted.