“Waste not, want not.”

This familiar proverb captures the essence of what every marina owner knows well: when we take care of our resources today, they take care of us tomorrow. Nowhere is this more relevant than in sanitary waste management at marinas and waterfront facilities. Clean water and clean operations aren’t just environmental responsibilities — they’re smart business.

If stormwater systems manage what flows across a site, then sanitary systems manage what flows through a site. Reliable, compliant, and environmentally sound sanitary systems help marinas enhance guest experiences, protect natural assets, and position themselves for sustainable growth.

Good for the Environment = Good for Business

Marinas operate at the intersection of nature and commerce. The cleaner the water, the healthier the ecosystem and the more desirable the marina. Customers want and will gravitate toward facilities that demonstrate care, cleanliness, and environmental integrity.

Thoughtful waste management supports far more than compliance. It safeguards water quality, reduces contamination risks, bolsters a marina’s reputation, and improves the boater experience. These investments lay the foundation for sustainable, future-ready growth and the infrastructure to support that vision.

From pump-out operations to restrooms, wastewater handling is a vital but often-taken-for-granted part of marina operations. When boaters arrive to find clean restrooms, dependable pump-out facilities, and odor-free grounds, they are more likely to treat the property with similar respect. These everyday actions strengthen trust, boost reputation, and improve long-term value.

Designs for a new transient marina at Fairport Harbor in Lake County, Ohio, include a restroom/administration building located near the docks with a convenient fish-cleaning station.

Assessing Your Waste Outputs

Every marina produces a unique combination of waste streams. Understanding these inputs is the first step toward designing a compliant, right-sized system. Restrooms, showers, laundry facilities, restaurants, bars, fish-cleaning stations, and boat pump-outs all contribute to the total wastewater volume.

Incorporating proper fish-cleaning station waste into a marina’s sanitary management plan is essential.

Fish waste is an often-overlooked concern and is treated under many regulations in a manner similar to human waste. While many municipal systems have the ability to accept fish waste, a well-planned private on-site system can manage it as well — provided it accounts for the system’s potential overall capacity. Requirements depend on local regulation, facility layout, and proximity to the body of water. Some marinas incorporate grinders at fish-cleaning stations or use dedicated holding tanks that require frequent pump-outs. Others partner with local farmers to repurpose fish waste as a nutrient-rich fertilizer.

What marinas generally cannot do is dispose of fish waste directly into marina basins or inland waters. While limited offshore disposal may be allowed in certain settings where local ecosystems naturally assimilate organic material, this practice is inappropriate for most marina environments. Particularly in inland and lake settings, this practice can create odor issues, attract pests, spread disease, and undermine the guest experience. Proper management of waste can help eliminate these risks and enhance facility cleanliness. Incorporating fish-cleaning-station waste into your facility’s sanitary management plan is essential.

Sanitary System Options for Marinas

Marinas generally have two primary sanitary system pathways:

1. Connection to a municipal sewer system
2. Installation of a Private Onsite Wastewater Treatment System (POWTS)

The best approach depends on geography, available land, proximity to existing utilities, and projected wastewater volume.

Tying into municipal systems: Urban and suburban marinas can often benefit from connecting directly to local municipal sewer infrastructure. In this scenario, pump-out stations move boat waste from the dock and other site amenities to onshore holding tanks where sewage lift stations transfer it “uphill” toward the municipal line. From there, force mains carry waste to the community’s wastewater treatment plant.

However, the capacity of the pipes and infrastructure can be a limiting factor. Many growing coastal and lakeside cities are already burdened by aging infrastructure and rapid development. Some utilities may be unable — or unwilling — to accept additional marina loads without significant upgrades. When municipal systems are at capacity, marinas must pursue creative alternatives.

Private Onsite Wastewater Treatment Systems (POWTS): In situations where municipal systems are at capacity, or in more remote or rural locations, POWTS can offer reliable and independent wastewater management opportunities. These systems include holding tanks (either singular or in succession for larger operations) for solid waste collection, primary treatment components, and dispersal components such as a drain field where treated effluent is filtered naturally through soil.

System types vary based on site conditions and may include gravity-fed systems, pressure distribution networks, or mound systems. Adequate land is essential. Drain fields must be large enough, and the site must provide sufficient vertical separation from groundwater per applicable state and local codes. Bedrock, high water tables, or limited land can restrict design options, but with proper engineering, drain fields can often be placed unobtrusively under parking lots, green spaces, or landscaped common areas.

A Private Onsite Wastewater Treatment System (POWTS) includes holding tanks for solid waste collection, primary treatment and dispersal components.

POWTS Case Study: a State of Wisconsin DNR Fish Hatchery

MSA engineers transformed an outdated State of Wisconsin fish hatchery into a modern, self-contained 400-acre hatchery campus. This project is comparable to a marina project in that it is a private, closed-loop system in a remote location that operates like a micro community. MSA drilled multiple wells, developed private water and wastewater treatment systems to service hatchery buildings, handled collection of fish waste, established two different avenues of treatment — one for human waste and one for fish waste — and established a safe, compliant outfall system to discharge treated waste into a local stream. Precision and proper treatment was essential, as the stream was a designated trout habitat and fish from the hatchery would ultimately stock Lake Michigan. The hatchery now produces 10 times more fish within its original footprint, replacing old technology with more efficient and effective systems to support fish-rearing across the region. It is a powerful example of POWTS system performance and how thoughtful design can turn complex regulatory and environmental challenges into operational success.

Regulations, Permitting, and Inspection

Regulatory frameworks vary widely depending on the state, municipality, type of system, and discharge method. Marinas connected to municipal systems must secure a connection permit, meet plumbing codes, incorporate grinders or lift stations where necessary, and undergo mandatory inspections before receiving a certificate of compliance. Utilities often require ongoing monitoring and documentation, including periodic pump-outs and adherence to daily or monthly flow limits.

POWTS installations face equally rigorous oversight, with state and local authorities dictating the design, siting, and maintenance requirements. Most states require re-inspection every three years and mandate that a licensed professional oversee installation, replacement, repair, or reconnection. Systems that discharge to surface waters may fall under federal permits such as NPDES, often renewed every 5–10 years. Failure to maintain these systems can result in notices of noncompliance, fines, or mandated upgrades.

Understanding these requirements — and staying ahead of them —ensures continuity of operations during busy seasons and protects the long-term investment of such a system.

Right-sizing Your Sanitary System

A system that works today may not be adequate tomorrow. Think about your current needs. Does your system adequately hold, process, and convey waste in all seasons, in all volumes of use? What about during surprisingly busy holiday weekends, peak summer boating season, or when hosting major events on the property? Similar to how residential homes with private septic tanks must match household size with tank size, marinas must also consider current average visitor rates, sanitary system capacity, peak usage, and the rate (or anticipated rate) of marina growth. An undersized system can trigger backups, odors, and the dreaded emergency pump-outs that disrupt the guest experience.

Looking ahead is equally important. If you’re planning for growth, new docks, the addition of a campground, RV park, or more lodging and dining options, your sanitary infrastructure must be designed to match or grow with you. Early planning with an engineer ensures future needs are considered and that upgrades can be made proactively and cost-effectively.

Right-sizing your sanitary infrastructure includes thinking about both present and future needs.

The Engineering Perspective

Marinas function as ecosystems — water-based, land-based, and everything in between. Yet too often, the systems serving these areas are designed as separate entities. MSA’s approach brings these elements together, ensuring docks, pump-out stations, restrooms, restaurants, and back-of-house facilities operate as one integrated system.

The key is treating wastewater planning as a foundational piece of the marina rather than an afterthought. When wastewater systems are engineered well, they reduce pollution risks at the sources, support regulatory compliance, and protect the natural resources that marinas depend on for successful, sustainable operations.

This article is the second in a series about “green marina” initiatives and was first published in Marina Dock Age Magazine in April 2026. The first article, Green Marinas Part 1 – Beyond Stormwater BMPs, focuses on thoughtful stormwater management.