The VID-NSP mandate the implementation of Ballast Water Best Management Practices for vessels equipped with ballast tanks (paragraph 40 CFR 139.10(c)). These vessels must maintain a ballast water management plan that addresses the uptake and discharge of ballast water, including vessel-specific systems and practices. They should minimize gravity drainage of ballast tanks while in port and use high sea suction methods when in port or shallow waters. Furthermore, vessels must avoid discharging or taking on ballast water in areas with coral reefs, ensuring such activities occur as far from coral reefs as practicable. Periodical cleaning of ballast tanks to remove sediment is required, with the discharge of sediment being prohibited. Sea chest screens must be maintained and kept intact. New laker vessels[1] equipped with ballast tanks must install, operate and maintain a ballast water management system (BWMS) that has been type-approved by the USCG.

The VID-NSP adopt the same numeric discharge standards for ballast water as established by VGP, including biological and biocide parameters (paragraph 40 CFR 139.10(d)). Discharges from a BWMS must not exceed the instantaneous maximum limits specified for various-sized living organisms, Toxicogenic Vibrio cholerae, Escherichia coli, intestinal enterococci, and four biocides: chlorine dioxide, total residual oxidizers, peracetic acid and hydrogen peroxide. Both MPN/mL and cfu/mL units are now specified for Escherichia coli and intestinal enterococcito to reflect the MPN outputs of newer microbiological test methods. Exemptions to these ballast water discharge standards apply to certain vessels, such as those less than or equal to 3,000 GT, that do not operate outside the Exclusive Economic Zone (EEZ).

The VID-NSP provide the following ballast water exchange and saltwater flush requirements (paragraph 40 CFR 139.10(e)):

• Any vessel that takes on ballast water in areas less than 200 nautical miles (NM) from shore that will later operate outside the EEZ and more than 200 NM from shore must conduct a ballast water exchange at least 200 NM from any shore before discharging that water. This exchange should be commenced not less than 200 NM from any shore and as early as practicable during the voyage.
• Ballast tanks that are empty or contain unpumpable residual water must be sealed, or ballast water exchange or saltwater flush must be conducted not less than 200 NM from any shore for a voyage originating outside the U.S. or Canadian EEZ; or not less than 50 NM from any shore for a voyage originating within the U.S. or Canadian EEZ.
• Certain vessels, such as those operating exclusively within the internal waters of the U.S. and Canada, are exempt.

Special requirements for ballast water exchange and saltwater flush apply to vessels entering the Great Lakes and those operating in the Pacific Region, with full details available in paragraphs 40 CFR 139.10(f) and 139.10(g).

All the above requirements apply to any vessel equipped with one or more ballast tanks, with certain exclusions. For example, vessels that carry permanent ballast water in sealed tanks that are not subject to discharge and vessels that discharge ballast water only to a reception facility are excluded from these requirements (paragraph 40 CFR 139.10(b)).

[1] New Laker  means a vessel 3,000 GT and above, and that operates exclusively in the Great Lakes and the St. Lawrence River west of a rhumb line drawn from Cap des Rosiers to Pointe-de-l'Ouest (West Point), Anticosti Island, and west of a line along 63° W longitude from Anticosti Island to the north shore of the St. Lawrence River, and constructed after the effective date of USCG regulations promulgated pursuant to CWA section 312(p)(5)(A)(i). (40 CFR 139.2)

The requirements of this section apply to discharges of wastewater from the bilge consisting of water and residue that accumulates in a lower compartment of the vessel's hull below the waterline, including any water and residue from a cargo area that comes into contact with oily materials or a below-deck parking area or other storage area for motor vehicles or other motorized equipment.

The discharge of bilgewater from any vessel must not contain flocculants or other additives except when used with an oily water separator or to maintain or clean equipment. Using additives to remove the appearance of a visible sheen is prohibited. For vessels of 400 GT and above, bilgewater discharge must occur when the vessel is underway, at least one NM from shore (if technologically feasible), and have an oil content of 15 ppm or less.

The discharge from boiler blowdown must be minimized in port.

The requirements of this section apply to discharges resulting from a vessel's cathodic corrosion control protection device, including sacrificial anodes and impressed current cathodic protection (ICCP) systems.

The spaces between any flush-fit anode and backing must be filled to remove potential hotspots for biofouling organisms. The vessel operator must consider using, but is not required to use, less toxic metals when selecting sacrificial anodes. It is recommended that vessels operating in harbors or estuaries with high pollutant loads use zinc as the preferred anode material due to concerns with pollutants causing aluminum anodes to passivate and lose effectiveness.

The requirements of this section apply to discharges resulting from a vessel's cathodic corrosion control protection device, including sacrificial anodes and impressed current cathodic protection (ICCP) systems.

The spaces between any flush-fit anode and backing must be filled to remove potential hotspots for biofouling organisms. The vessel operator must consider using, but is not required to use, less toxic metals when selecting sacrificial anodes. It is recommended that vessels operating in harbors or estuaries with high pollutant loads use zinc as the preferred anode material due to concerns with pollutants causing aluminum anodes to passivate and lose effectiveness.

Anchors and anchor chains must be rinsed of biofouling organisms and sediment when the anchor is retrieved. Discharging biological organisms, sediment, precipitation and seawater from any chain locker is prohibited in port.

Anchors and anchor chains used beyond the waters of the contiguous zone must be rinsed of biofouling organisms and sediment prior to entering the contiguous zone. This requirement may be met by rinsing when the anchor is retrieved at the commencement of the voyage or when the anchor was last retrieved on a previous voyage, so long as the rinsing occurs after the last use of the anchor beyond the waters of the contiguous zone.

This section applies to the discharge of washdown and runoff from decks, well decks, and bulkhead areas, including precipitation, condensation, seawater spray and wash over, and flooding, as well as waters pumped from below deck on a barge.

Coaming or drip pans must be used for machinery that is expected to leak or otherwise release oil on the deck; accumulated oil must be collected. Where required by an applicable treaty or convention or the USCG, the vessel must be fitted with and use physical barriers, such as spill rails and scuppers, during washdowns.

Control measures must be used to minimize the introduction of on-deck debris, garbage and other materials into deck washdown and runoff (paragraph 40 CFR 139.15(d)). Decks must be kept in broom clean condition whenever the vessel is underway and before washdowns. Any soap, cleaner, or detergent used must be minimally toxic, phosphate-free and biodegradable.

Discharges from deck washdowns should be minimized while in port. Barges that discharge water pumped from below deck must minimize the contact of below-deck condensation with oily or toxic materials and any materials containing hydrocarbons.

The discharge resulting from the cleaning of desalination and purification systems with toxic or hazardous materials is prohibited.

The discharge of untreated accumulated water and sediment from any elevator pit is prohibited.

The VID-NSP establish limits for the following parameters in the discharges from the operation and cleaning of any exhaust gas cleaning system (EGCS) and exhaust gas recirculation (EGR) system: pH, PAHs (Polycyclic Aromatic Hydrocarbons), turbidity, suspended particulate matter and nitrates plus nitrites. The same limits apply for pH, PAH and turbidity for any EGCS water retained in a temporary storage tank prior to discharge.

The discharges of sludge or residues generated from the treatment of EGCS or EGR washwater or bleed-off water are prohibited.

For a vessel operating on fuel that meets the sulfur content limits specified in Regulation 14 of MARPOL Annex VI, discharge of EGR bleed-off water is excluded from the requirements above if the vessel does not retain the EGR bleed-off onboard in a holding tank prior to discharge, is underway and not in port.

For a vessel not operating on fuel that meets the sulfur content limits specified in Regulation 14 of MARPOL Annex VI, discharge of EGR bleed-off water retained in a holding tank is prohibited unless the vessel is underway, not in port and in compliance with the discharge standard requirements above.

The table below summarizes the main differences and clarifications between the VID-NSP and VGP regarding the discharge standards for exhaust gas emission control systems. It is important to note that VGP did not address EGR discharges, primarily because EGR systems are relatively new to vessels.

The VID-NSP establish requirements for discharges from fire protection equipment, including discharges for secondary purposes, such as anchor and anchor chain rinsing and deck washdown. These requirements do not apply during emergencies or when compliance would compromise the safety of the vessel or life at sea.

The discharge of fluorinated firefighting foam is prohibited unless required for certification or inspection or by the marine inspector to ensure vessel safety and seaworthiness.

The discharge from fire protection equipment during testing, training, maintenance, inspection or certification is prohibited in port unless the intake is from surrounding waters or a potable water supply and contains no additives or, if required, in port for certification or inspection or by the marine inspector for safety purposes. The discharge for secondary uses is prohibited in port unless the intake is from surrounding waters or a potable water supply, contains no additives and the discharge meets applicable requirements for secondary use.

The discharge of untreated gas turbine washwater is prohibited unless it is infeasible to do otherwise.

These requirements apply to graywater discharges, except for those from commercial vessels on the Great Lakes, which are subject to 40 CFR 140 and 33 CFR 159. The introduction of kitchen waste, food, oils and oily residues into the graywater system must be minimized. Soaps, cleaners, detergents and other substances used by vessel operators or provided by vessel operators to persons onboard and discharged in graywater must be minimally toxic, phosphate-free and biodegradable.

Vessels subject to paragraph 40 CFR 139.21(e) must meet the following numeric discharge standards established in paragraph 40 CFR 139.21(f): 

The table below summarizes the main differences and clarifications between the VID-NSP and VGP regarding the discharge standards for graywater systems.

Graywater discharge is prohibited from any vessel:

• Within 3 NM from shore that voyages at least 3 NM from shore and has remaining available graywater storage capacity, unless the discharge meets the specified numeric standards; and
• Within 1 NM from shore that voyages at least 1 NM from shore but not beyond 3 NM from shore and has remaining available graywater storage capacity, unless the discharge meets the specified numeric standards.

Except for vessels subject to paragraph 40 CFR 139.21(e), graywater discharge from non-commercial vessels operating on the Great Lakes must not exceed 200 fecal cfu per 100 mL and contain no more than 150 mg/L of suspended solids.

These requirements apply to the discharge of anti-fouling coatings, biofouling organisms, and other materials from vessel hulls and associated niche areas. The transport of attached living organisms and passive discharge of biofouling must be minimized when vessels enter U.S. waters from outside the EEZ or travel between Captain of the Port (COTP) Zones.

Anti-fouling coatings applied to vessels must be specific to the vessels’ operational profile and equipment, and biocidal coatings should have appropriate biocide release rates and components that are biodegradable once separated from the vessel surface. Anti-fouling coatings must be applied, maintained and reapplied according to manufacturer specifications, including thickness, method of application, and lifespan of the coating. Furthermore, they must not contain cybutryne, tributyltin (TBT) or any other organotin compound used as a biocide. Additional requirements for anti-fouling coatings are provided in paragraph 40 CFR 139.22(c).

Cleaning should be conducted in drydock when practicable, and hulls must be managed to minimize biofouling. Cleaning must minimize damage to anti-fouling coatings, minimize biocide release and adhere to the requirements found on the coating manufacturers’ instructions and any applicable FIFRA label. Discharges from in-water cleaning without capturing macrofouling or copper-based coatings in copper-impaired waters within the first 365 days after application are prohibited. In-water cleaning must not be conducted on any section of an anti-fouling coating that shows excessive cleaning actions or blistering due to the internal failure of the paint system. Any soap, cleaner, or detergent used must be minimally toxic, phosphate-free and biodegradable (paragraph 40 CFR 139.22(d)).

There are no additional discharge-specific requirements that apply to the discharge of washwater from an inert gas system and deck seal water when used as an integral part of that system.

The discharge of motor gasoline and compensating discharges in federally protected waters is prohibited.

These requirements apply to discharges from machinery containing no oil as detailed in paragraph 40 CFR 139.25(a). It is prohibited to discharge untreated non-oily machinery wastewater and packing gland or stuffing box effluent with toxic or bioaccumulative additives or oil in harmful quantities.

Except for unintentional releases from overflows across the decks and into overboard drains caused by weather, vessel traffic or other navigational factors, the discharge of pool and spa water must occur only while the vessel is underway unless deemed unfeasible. Such discharges must meet the following numeric standards, which are the same as those established by VGP:

• For chlorine disinfection: total residual chlorine must be less than 100 µg/L. 
• For bromine disinfection: total residual oxidant must be less than 25 µg/L.  

The requirements for discharges from refrigeration, air conditioning and similar chilling equipment specify that the direct overboard discharge of condensate that contacts toxic or hazardous materials is prohibited.

The requirements for discharges from seawater piping systems apply in port and during layup. Seawater piping systems must be inspected, maintained and cleaned as necessary to minimize the accumulation and discharge of biofouling organisms. Seawater piping systems that accumulate macrofouling must be fitted with a Marine Growth Prevention System (MGPS) addressing the level, frequency, and type of expected biofouling, as well as the design, location, and area in which the system will be used.  An MGPS must include one or a combination of the following methods: chemical injection, electrolysis, ultrasound, ultraviolet radiation, electrochlorination, antifouling coatings, cupro-nickel piping, or glass-reinforced epoxy-based composite piping. Upon identification of macrofouling, reactive measures must be implemented; however, discharges resulting from these measures are prohibited while in port.

The discharge of water from inside the sonar dome is prohibited during maintenance or repair. Any discharge from the use of bioaccumulative biocides on the exterior of the sonar dome is also prohibited when non-bioaccumulative alternatives are available.