Christie DEP’s Proposed Weakening of Sewer “Capacity Assurance” Program Jeopardizes Water Quality & Increases Risks To Drinking Water

Another rollback of a longstanding and effective protection for clean water

Incredibly, DEP is proposing a rule that they KNOW will increase the probability of NJPDES permit violations at sewage treatment plants and that the KNOW will reduce the number of plans required to correct deficiencies and better protect water quality.

The DEP has gotten a lot of criticism and media attention for recently proposing major overhauls of two critical clean water rules: the Flood Hazard “stream encroachment” rules and the Water Quality Management Planning rules (“WQMP).

But lost in the shadow of the controversy over those major rules, is DEP’s proposal to seriously weaken a little known, important, effective, and highly technical program called the “Capacity Assurance Program” (CAP).

The purpose of the CAP is to protect clean water by preventing violations of sewage treatment plant permits related to excessive wastewater flows.

Each sewage treatment plant is designed to handle a certain flow of wastewater.  Every DEP sewage treatment plant permit includes limits on flows and the volume of plant discharge to a stream or river to protect drinking water or the aquatic life of the river.

Flows are the foundation of the entire system.

Wastewater flows to a sewage treatment plan can vary based on things like when people flush their toilets and take showers, rainfall, snowmelt, or as a result of infiltration and inflow to the pipes in the collection system.

The basic idea is that as a sewage treatment plant approaches its permitted capacity, the risks of excessive flows and permit violations increase, because there is less “cushion” or slack in the system. For example, if a sewage treatment plant is designed and permitted to treat 10 million gallons per day (MGD) and the actual flow is only 5 MGD (50% of capacity), there’s a lot more ability to handle variations in flow than if the flow is 9 MGD (90% of capacity).

Here’s how DEP describes the current CAP Progam:

The Capacity Assurance Program assesses how a treatment plant owner will prevent a plant from exceeding its permitted design flow capacity. This program is required when a treatment plant’s actual and permitted flows exceed 80% of the permitted design capacity.

If a treatment plant fails to meet its NJPDES discharge permit limits, it can adversely impact the waterway it discharges into, threatening drinking water supplies and the habitat of aquatic plants and animals. To prevent further harm, a sewer ban is implemented in the areas served by the affected treatment plant. This measure protects the receiving water from additional damage until the problem can be corrected. To avert the need for a sewer ban, the Capacity Assurance Program serves as a planning tool which is implemented when committed flows (anticipated flow from permitted projects not yet constructed) reach 80% of a treatment plant’s permitted design capacity. This helps treatment plant owners decide how a plant’s remaining flow capacity will be used and whether an equipment upgrade is necessary to assure future capacity.

Under current rules, a Capacity Assurance Plan includes important planning and water quality protections: (DEP proposal at page 4)

The capacity assurance program under the existing rule must include, at a minimum: measures for water conservation; maximization of treatment capacity at a minimum cost; reduction of infiltration/inflow (I/I) where appropriate; construction of improvements; disconnection of roof leaders, sump pumps, and other sources of inflow into sanitary sewer lines and their connection into storm sewer lines where available and to the extent feasible; submission of a WQM007 form on a quarterly basis; and preparation for the imposition of a self- imposed sewer connection ban.

Water conservation is always a good thing. As is reduction of I/I and the threat of a sewer connection ban is a big stick that is sure to get people’s attention.

The Christie DEP is proposing to significantly weaken the current CAP Program in three ways:

1) increasing the 80% trigger for requiring submission of a “capacity assurance plan” to 100%. That virtually guarantees that some percentage of sewage treatment plants will violate their permits and threaten water quality and drinking water. The definition of flow is also changed in a way that will reduce the flows and avoid the trigger for submitting a CAP plan;

2) increasing the current 3 month period for determining whether the 80% threshold is exceeded to a 12 consecutive month period. DEP’s own analysis shows the this will significantly reduce the number of sewage treatment plants that must submit a capacity assurance plan; and

3) shifting the requirement to submit a CAP from the current joint  approach where municipalities and the sewer authority are required to submit plans to only the sewage treatment plant. This will undermine protections because both towns and sewer authorities must take actions to implement a CAP.

The Department claims to justify this by an analysis and finding of a “weak” correlation between exceedence of the current 80% threshold and actual sewage treatment plant permit violations.

But even a “weak” 0.19 statistical correlation between exceedence of the 80% threshold and actual permit violations will still result in a significant increase in permit violations at the sewage treatment plants.

The DEP also knows that the proposed changes will result in far fewer CAP Plans submitted:(proposal at p. 13)

Based on the above evaluation, the Department determined that 68 percent of the facilities (129 of 189 facilities) would have triggered the CAP rule requirements at the existing threshold of 80 percent committed flow to permitted flow over a three-month period, and 18 percent (34 facilities) would trigger the requirements if the average reported flow over 12 consecutive months exceeded the permitted flow.

Incredibly, DEP is proposing a rule that they KNOW will increase the probability of NJPDES permit violations at sewage treatment plants and that the KNOW will reduce the number of plans required to correct deficiencies and better protect water quality.

As DEP’s own CAP program summary states, these violations would “adversely impact the waterway it discharges into, threatening drinking water supplies and the habitat of aquatic plants and animals.”

The DEP’s own rule proposal documents these threats:(proposal at p. 20)

the CAP requirements have in ensuring hydraulic overloads that could result in violation(s) of the treatment plant’s NJPDES permit discharge limits or unpermitted discharges are avoided. Improperly maintained and operated treatment works create the potential for adverse environmental impacts and serious health risks, such as those resulting from raw sewage overflows into basements, storm sewers, and waterways, as well as the release of untreated or partially treated sewage into the surface and ground waters of the State.

The DEP proposal is incredibly short sighted and will undermine the DEP’s ability to prevent permit violations and protect water quality and cause more NJPES permit violations.