Wastewater options must be reviewed

BY JOHN BOLOGNA, PE

There are billions of taxpayer dollars at stake and towns can’t afford to make decisions that spend money needlessly.

Residents of coastal communities in New England are facing difficult decisions about managing their wastewater and its impact on the fragile environment. Degradation of the coastal waterways from excessive nutrient loading will not only have a drastic impact on the environment, but will also adversely impact quality of life and future economic development of the region.

Ask any town manager, planner or regulator what their most important concerns are and they are likely to tell you 1) water quality and supply, 2) community preservation and quality of life and 3) economic development – not necessarily in that order. This is not too different from the so-called “triple bottom line of sustainability”: ecological integrity, social equity and economic reality. In other words, sustainability, in order to be achievable, has to be affordable.

No one disagrees that something needs to be done to clean up the water. The question is how do we go about doing this, how much is it going to cost and how is it going to be paid for? Clearly there are ecological as well as economic benefits to maintaining clean coastal waters; some would argue there is a moral responsibility to be good stewards of the environment that we are entrusted to protect for ourselves and our posterity. However, current plans to implement large centralized systems are extremely costly and just as burdensome on current and future generations. Fortunately, there are alternate solutions to plans currently being developed by local municipalities that need to be considered.

From an engineering and management point of view, a comprehensive, centralized wastewater collection and treatment system makes sense. The ability to collect and treat wastewater flow at a central location has many advantages from both an operations and management point of view. But when one analyzes the economic cost associated with the implementation of these types of systems, citizens are rightly asking, “What are the alternatives?”

The good news is that there are alternatives; the bad news is that they are being summarily dismissed as ineffective or cost-prohibitive.

In our view, the Cape Cod towns that are currently rolling out plans that recommend implementation of centralized systems have not adequately considered alternatives that may be more beneficial and less costly. Recent case studies indicate that distributed wastewater treatment systems, utilizing current state-of-the-art package treatment plants, can result in significant savings to the local communities. Locally, there are a number of these package treatment plants in operation at both private and public facilities, and they are proving to be cost-efficient and effective in removing pollutants from the wastewater streams.

With decentralized treatment plants, wastewater is discharged on site, recharging the groundwater locally instead of removing it to another watershed. With centralized sewage treatment plants, groundwater from an entire town or region is discharged at one location, effectively unbalancing the recharge of the groundwater aquifer.

Raising the ire of citizens is the astronomical cost associated with implementing centralized sewer systems. Ranging in cost from $300 to $600 million per town, the total Cape-wide cost will be in the billions of dollars if each of the fifteen towns installs a centralized system. These types of numbers are rightly being scrutinized by citizens who can “do the math” and see, that no matter how it is financed, the cost of centralized systems approaches $50,000 to $80,000 per housing unit. Rightfully, they are asking their towns if there is a less-costly way of managing wastewater.

Decentralized sewage treatment plants have not been thoroughly investigated to determine their viability as an alternative to the centralized treatment plants that are being planned. In part, their use has been dismissed because the scientific studies have indicated that all sewage-borne nitrogen must be removed from certain watersheds, and no matter how effective, no sewage treatment plant can remove all nitrogen from the treated effluent. Their use has also been dismissed because they have been viewed as being ineffective or unreliable.

Assessing the viability of decentralized treatment plants requires that the problem be broken into two parts: 1) proper diagnosis of water quality needs, and 2) proper cost benefit analysis of the options and alternatives.

The Comprehensive Wastewater Management Plans that are being prepared by a variety of engineering companies for local towns are all being formulated based on the Total Maximum Daily Loads that have been determined by the Massachusetts Estuaries Program, which in turn are based on computer modeling studies done by the School for Marine Science and Technology. Recent independent reviews have raised questions about the validity of these TMDLs, or more correctly, the validity of the computer model that is being used by SMAST to determine the condition and health of the estuaries. The computer model has not been made available for peer review, so it has not been possible for independent scientists to validate SMAST’s results and conclusions. Peer review and validation of the computer model is a necessary first step for engineering consultants and towns to properly evaluate wastewater needs and treatment options.

Secondly, there needs to be a proper analysis of the best in class of Innovative and Alternative systems currently available. Our experience in managing close to 150 small package systems shows that these systems work. The better systems are proven to meet DEP discharge standards of 10 mg/L total nitrogen, and can produce an effluent with 3 to 5 mg/L total nitrogen.

There are billions of taxpayer dollars at stake and towns can’t afford to make decisions that spend money needlessly. Questions raised about the validity of SMASTs computer model and the resulting TMDLs suggest that more work needs to be done before any town goes forward with its CWMP. Towns owe it to their citizens to consider all of the data before going forward with any plan, including a fair and honest assessment of the alternatives once the science has been validated. ■

John A. Bologna, PE, is President of Coastal Engineering Company Inc. He can be reached at (508) 255-6511 or jbologna@CoastalEngineeringCompany.com.


Published in Cape & Plymouth Business May 2010