Recreation
Management
United States Department of Agriculture
Forest Service
Technology &
Development Program
TechTips
July 2004
2300
0423 1304—SDTDC
PORTABLE VAULT TOILET SERVICE UNIT
Brenda Land, Sanitary Engineer
BACKGROUND
Septic tank service companies pump most U.S.
Department of Agriculture (USDA) Forest Service vault
toilets. These companies have the equipment, training,
and contacts at a municipal wastewater treatment plant
that are required to pump vault toilets and to discharge
the waste safely and legally. However, some USDA
Forest Service vault toilets are in remote locations
where such service is unavailable, or the vault toilets
are inaccessible using standard equipment. In many of
these cases, USDA Forest Service employees have to
pump the toilet vaults with out-of-date or unsuitable
equipment.
SDTDC developed the specifications and Marsh
Industrial fabricated and manufactured a small vacuum
pump service unit for vault toilets. The unit has a 500gallon waste tank and a 200-gallon freshwater tank. The
tanks may be permanently trailer-mounted or skidmounted for use on a multi-use trailer. When full of
water and wastewater, the unit weighs nearly 3 tons,
making it unsuitable for the bed of a pickup truck. In
2003 a complete unit, with trailer, cost approximately
$11,000. Contact Marsh Industrial for their current price.
Field personnel asked the San Dimas Technology and
Development Center (SDTDC) to find a better method to
empty vault toilets. The grinder pump and poly tank
used by districts to empty toilet vaults caused frequent
pump jams that had to be cleared by hand.
Vacuum pumps are a more sanitary way to pump vault
toilets. If a vacuum hose is clogged, pressure can be
reversed to clear the clog, which eliminates the risk of
human contact with vault toilet waste. The waste does
not go through the vacuum pump, so the pump does not
become clogged with debris.
Figure 2—Marsh Industrial toilet service unit.
French Glen Blacksmiths will also fabricate a vacuum
pump service unit to USDA Forest Service
specifications. In 2002, a trailer-mounted service unit,
with a 500-gallon waste tank and vacuum pump and a
500-gallon clean water tank and pressure pump, cost
$12,000. Contact French Glen Blacksmiths for options
and current prices.
Figure 1—Vacuum pumping a vault.
For additional information, contact: Recreation Management Program Leader, San Dimas Technology & Development Center,
444 East Bonita Avenue, San Dimas, CA 91773–3198; Phone 909–599–1267: TDD: 909–599–2357; FAX: (909)592-2309
Lotus Notes: MailroomWOSDTDC@FSNOTES • Intranet(web site):http://fsweb.sdtdc.wo.fs.fed.us • Internet e-mail:mailroom_wo_sdtdc@fs.fed.us
Many local fabrication shops can fabricate a toiletservice unit. To ensure that your quotes are comparable,
specify the desired pump sizes, tank sizes, and
material, as well as hose sizes and length and any other
required options. The Marsh Industrial unit uses a 12volt pressure pump with a 4.5-gallon per minute at 20/
40 pounds per square inch and a 9-horsepower belt
drive gasoline vacuum/pressure pump. It has a 200gallon freshwater reservoir and a 500-gallon wastewater
reservoir. The freshwater hose is 5/8 inch in diameter by
50 feet with a spray nozzle. The suction hose is 2 inches
in diameter by 30 feet with a wand.
Figure 3—French Glen Blacksmith toilet service unit.
Information contained in this document has been developed for the guidance of employees of
the Forest Service, United States Department of Agriculture (USDA), its contractors, and
cooperating Federal and State agencies. The USDA Forest Service assumes no responsibility
for the interpretation or use of this information by other than its own employees. The use of
trade, firm, or corporation names is for the information and convenience of the reader. Such
use does not constitute and official evalution, conclusion, recommendation, endorsement, or
approval of any product or service to the exclusion of others that may be suitable.
For further information regarding Marsh Industries or
French Glen Blacksmiths, contact Brenda Land, project
leader, by phone at 909–599–1267, ext 219, or by email at bland@fs.fed.us.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and
activities on the basis of race, color, national origin, sex, religion, age, disability, political beliefs,
sexual orientation, or marital or family status. (Not all prohibited bases apply to all programs.)
Persons with disabilities who require alternative means for communication of program information
(Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600
(voice and TDD).
To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326-W,
Whitten Building, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410 or call
(202) 720-5964 (voice and TDD). USDA is an equal opportunity provider and employer.