Most Type lls use some combinaton of chemical, biological, electrieal, or incinerating methods in the treatment process. Many of these systems use chlorine or other disinfectants.
Type III MSDs are designed to prevent the discharge of human waste in any form from boats. These devices include recirculating and incinerating MSDs and holding tanks. Holding tanks are the most common kind of Type III MSD found on recreational boats.
The Type III system, when empted at an onshore pum-out station, may be the best environmental altemative because it produces no direct chemical or water pollution. In additon, the total cost of installing and operating a Type III MSD on a boat is comparatively low, even when including possible pump-out fees. However, depending upon local regulations and regulations of intended boatng destinatons, installation of a Type I or II device coupled to a holding tank, may provide the best choice for certain boat owners. To help decide, consult a local MSD dealer or the manufacturers of various MSD products.
In some states or water management districts certain areas may be designated as "no-discharge zones." In such zones, Type III MSDs or "porta-potties" are the only acceptable waste disposal systems, since they are the only types that do not discharge into the water.
ACTIONS
1. Use holding tanks or "porta-potties" and onshore pumping stations to keep your sewage out of the water. For a list of pum-out stations, contact your state boating law administrator.
2. Select and use holding tank deodorant chemicals with care.
3. Keep your MSD properly maintained.
4. Encourage the development of more onshore pumpout stations. Let the owner of your marina know that you and other boaters need a local pum-out facility and will use the station if it is installed. Federal funds have recently become available for establishing pumpout facilities.
5. When planning a trip, check the location of pum-out facilities on your route or near your destination and use them. Consult cruising guides and boating almanacs for pump-out facilities when traveling beyond your home port.
6. When you are docked, use onshore restroom and bathhouse facilites. This will minimize the need to pump out your system.
7. If you have a Type I or II device, always flush your system in open water, preferably in a depth of 20 feet or more. This will allow natural tidal or other water movements to disperse the waste materials more quickly and completely. Additionally, discharging in deep rather than shallow waters greatly reduces damage to shellfish beds.
