Franklin Drinking Water Plant -- Archives

HRWA Comments on First Drinking Water Plant Application 2003

The new permit application proposes to expand Franklin’s drinking water plant from 2 to 4 million gallons per day and is based upon stopping water withdrawals when the river flow gets below a specific cutoff level. City Consultant Water Availability Study - Available in print form. Please contact HRWA for copy..
City Consultant Water Plant Design Study - Available in print form. Please contact HRWA for copy. Working with the city, HRWA funded analyses of what river flows are needed to ensure that water quality violations do not occur downstream from the withdrawal point and the sewage treatment plants.

Too Much Effluent Currently Permitted

HRWA’s contracted water quality analysis found that the river’s natural low flow conditions are not enough to handle all of the effluent currently permitted to be discharged. Franklin’s large, 12 million gallon a day (MGD) sewage treatment plant, which is currently only operating at half its full capacity (6 MGD), is just a few river miles downstream from where the water is withdrawn for the city’s drinking water plant. During the low flow season, removing any river flow reduces the ability of the river to handle effluent and still meet water quality standards. HRWA’s study found that the proposed withdrawal cutoff point for the drinking water plant is far too low. Violations of dissolved oxygen standards were recorded by TDEC when flows in the river were well above the proposed cutoff point. HRWA-AquAeTer River Flow Requirements to Handle Sewage Discharge Study
City Consultant Comments on WQA
Rebuttal to Consultant Comments on WQA

Plant Expansion Will Incur Losses

HRWA’s contracted economic analysis of the proposed drinking water plant expansion was done to fulfill state regulations requiring that alternatives be assessed in permit proposals. When the plant expansion was analyzed using standard accounting methods (present value analysis) including operating costs, capital expenditures, the variation in Harpeth River flows, and the existing city contract for water purchases, the analysis found that the plant expansion will incur financial losses both initially and in the long term. The analysis demonstrated that it would be more cost effective for Franklin to purchase all of its water from Harpeth Valley Utility District (HVUD) and shut down its existing drinking water plant. Currently, Franklin purchases 66% - 75% of its drinking water from HVUD which gets its water from the extremely large Cumberland River. The transition involved in purchasing all drinking water from HVUD would take about two years based on the city’s studies.

City Consultant Comments on EA
HRWA Cover Memo for Rebuttal of EA
Rebuttal to City Consultant Comments on EA

Dissolved Oxygen in Harpeth Extremely Low

Shutting down Franklin’s existing drinking water plant will also allow for the removal of the 50 year-old low head dam which, in addition to the withdrawals, exacerbates water quality problems by stopping the river’s flow entirely many times during the low flow season. Removing the dam is an important step toward addressing the dissolved oxygen problems in the river caused primarily by the downstream sewage treatment plants. Analysis of water quality conditions in the Harpeth by EPA combined with additional surveys of dissolved oxygen levels by TDEC and HRWA found that levels have been extremely low for days at a time at locations starting in Franklin below the dam, and below each of the sewage treatment plants and as far downstream as Bellevue (over 40 river miles away). See HRWA Water Quality Analysis Days of such low D.O. levels can lead to fish kills as well as pose threats to public health that would limit recreational use of the river at a time when Franklin is making major investments in parks, all connected by the Harpeth.

HRWA-TDEC Dissolved Oxygen Survey 2006 - Available in print form only. Please contact HRWA.

Effluent in River Leads to Low Dissolved Oxygen

Public input will also be needed regarding the three sewage treatment plants’ permits that are currently up for evaluation and renewal. HRWA’s analysis shows that the violations of the state dissolved oxygen standards during the low flow season is predominately caused by treated effluent. As a rule of thumb, rivers can maintain water quality standards if effluent discharge is about 10% or less of the flow. Analysis of the Harpeth flows that occurred when TDEC recorded consistent D.O. violations found that the AVERAGE percent of effluent in the river was already 29% (climbing as high as 73% at times). Had the city’s sewage treatment plant been processing at its full capacity, the AVERAGE percent would have been 70%. See HRWA Water Quality Analysis

Along with stopping the water withdrawals, another part of the solution to the low dissolved oxygen problem will be to reduce the amount effluent being introduced to the river during the low flow season. Since the City’s sewer plant is operating at half its capacity there is time to develop cost effective solutions. Franklin has already instituted an effluent reuse program that sends effluent to a nearby golf course and requires new development to use effluent to water landscaping. Since much summer water use is related to watering lawns, using effluent for irrigation helps reduce the demand for drinking water. Solutions will also involve treating the effluent that goes into the river during the low flow season to a higher standard. See HRWA-AquAeTer Presentation to City Low dissolved oxygen levels are also found in the river’s headwaters. HRWA has developed a community based headwaters restoration plan in Eagleville with state grant funds to improve water quality in the river before it reaches Franklin and the sewage treatment plants. (Details coming to web soon.)

Decisions Will Affect Finescale Darter

Instituting management decisions that will improve water quality is critical to maintaining the Harpeth’s fish populations that include species such as the fine scale darter, that still occur in downtown Franklin and are now only found in two rivers in the world—the Harpeth and the Red rivers. See Harpeth River Fish Study 2006 With funding from the World Wildlife Fund, Nissan, Patagonia and individuals, HRWA will be working with the EPA, TDEC, the sewer plant permitees, other state and federal agencies and outside experts to create a long term, cost effective plan that will improve water quality in the river for public health, fish and aquatic life and recreational enjoyment.