US20100050330A1

US20100050330A1 - Fixed location, ultra-low flush, sewage-holding vessel restroom system

Info

Publication number: US20100050330A1
Application number: US12/543,652
Authority: US
Inventors: Kenneth Earlywine
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-08-29
Filing date: 2009-08-19
Publication date: 2010-03-04

Abstract

A restroom system can include a fixed-in-place restroom building, a flush toilet housed in the restroom building, a water supply system in communication with the flush toilet, and a sewage-holding vessel in communication with the flush toilet. Sewage can be received in the flush toilet and water can be supplied from the water supply system to the flush toilet in an amount less than 1 gallon of water per flush. Sewage effluent can be flushed from the flush toilet, transported to the holding vessel, and extracted from the sewage-holding vessel and to a sewage hauling vehicle tank. The sewage effluent can be transported away from the restroom system in the sewage hauling vehicle tank.

Description

RELATED APPLICATION

This application is a non-provisional application claiming priority to U.S. Provisional application No. 61/093,079, filed Aug. 29, 2008, entitled Fixed-in-Place Stand-Alone Flush Restroom, which is incorporated herein by reference.

TECHNICAL FIELD

The description relates to fixed-in-place restroom systems, and in particular to the use of ultra-low volume flush toilets and sewage-holding vessels in such restroom systems.

BACKGROUND

Fixed building restrooms currently employ vault toilets, composting toilets, or conventional flush toilets. As used herein, fixed building, fixed-in-place, fixed location, and similar terms refer to restroom buildings being attached to a permanent foundation and/or partially placed within an excavation. These terms can be contrasted with movable restrooms, which can include standard “porta-potties”, mobile restrooms, restrooms mounted on trailers, floating restrooms, and the like. A restroom building is a building whose primary features include restroom features, such as toiletry, washroom, and/or shower features. Vault toilet buildings are equipped with toilet risers through which human waste and urine are deposited to a waste storage vault below, without mechanical assistance. Composting toilet buildings have a composting chamber located below the toilet riser instead of a waste-holding tank.
These restroom options have advantages and disadvantages. Restroom buildings employing vault or composting toilets do not require water, sewer, or electrical service and thus are well suited to remote locations, needing only heavy truck access for installation, maintenance, and waste removal. However, restrooms employing either vault or composting toilets are vulnerable to users depositing inappropriate materials in them.
In addition, the public generally perceives vault toilets as being unsanitary, smelly, and unsightly (being able to peer down at human waste in the holding tank). Debris and high concentrations of toilet paper deposited in vaults makes pumping operations difficult, unsanitary, and expensive. Vault waste disposal is a problem in some areas due to its concentration of urine and waste and because toxic materials are sometimes added to reduce odors. The waste is concentrated because, unlike flush toilets, no water dilutes the waste. Many small wastewater treatment plants are unable to process undiluted vault waste. Consequently, the waste must either be diluted or hauled to a larger wastewater treatment plant that can process undiluted sewage.
Occasionally, restroom buildings are equipped with composting toilets. These restrooms are very expensive to purchase and maintain. They are labor intensive, frequently do not work, and potentially endanger employees through pathogen exposure and confined space hazards.
Restrooms equipped with conventional flush toilets have none of these disadvantages. However, they require connection to a pressurized water system and to a sewer or on-site septic system. These utilities are often unavailable in remote locations, are expensive to construct, and may not be feasible. In many locations, flush restrooms also require heat to keep the water lines from freezing. Accordingly, in locations that do not have water, sewage, or electrical services, flush toilets may be impractical and permanent restroom buildings are typically equipped with vault toilets. Conventional flush toilets and urinals have environmental issues related to their use of large amounts of water.
In an effort to make vault toilet restroom buildings more acceptable to the public, many fixed vault toilet restrooms have been designed to meet the specifications of the “sweet smelling technology”, or “SST”, developed by the U.S. Forest Service over the past 20 years. The main SST design features for these buildings include the following:

- waste vaults made of plastic or sealed concrete;
- large black plastic stacks that use solar gain and flue design to create negative pressure in the sewage vaults, which in turn creates a downdraft through the toilet riser to direct odors away from the interior building spaces;
- access to the sewage vault through an exterior manhole for pump-out servicing (previously, vault toilets were pumped out through the toilet riser);
- provision of separate sewage vaults for each toilet riser in order to eliminate cross-flow conditions wherein air passes down one toilet riser, over the waste material below and then out another toilet riser into the building; and
- fresh air vents located to minimize the possibility of drafts bringing odors up the toilet risers into the occupied spaces.

Moveable ultra-low volume flush toilet restrooms have been commercially available for many years. However, similar technology has not been developed for application in fixed restroom buildings. Two examples of portable toilet restrooms with self-contained sanitation systems (i.e., sanitation systems that do not require sewer or on-site septic systems) include those manufactured by Water-Loo, Inc; and Turkstra. The reason these moveable restroom designs have never been adapted as fixed location restrooms appears to be primarily due to their high cost per-use. The Water-Loo model was designed for railroad crews and is equipped with wheels set on the railroad tracks. The treated effluent is leaked onto the railroad tracks below. The cost per use is high, but for such specialized use this is not a primary concern. The Turkstra portable restroom is promoted as a portable golf course toilet where high cost per use might be acceptable.
Joe Welch Companies, Inc. manufactures a self-contained moveable flush restroom that is fitted with wheels and can be connected to a conventional trailer hitch for easy relocations. These units were first delivered in 1997 to the National Park Service at Lake Powell National Recreation Area. They were specifically designed by the engineering staff at Glen Canyon National Recreation Area for environmental protection as moveable units that could be located and relocated along the fluctuating shorelines of Lake Powell. Previously, single user portable vault toilets (of the kind used on construction sites) were placed on the lakeshore. These proved to be so unpopular that beach visitors resorted to unsanitary practices in and near the water, causing high fecal coliform counts in the lake water. This led to multiple beach closures. Accordingly, the moveable flush units were designed primarily to protect the environment. In this unique situation, the possibility of a relatively high cost per use was not a deterrent to their development. To date, it is believed that nearly all of the fully self-contained moveable flush toilet restrooms built by Joe Welch Companies, Inc. have been purchased by the National Park Service, although some may have been purchased by individuals. Public marketing efforts by Joe Welch Companies to sell these units appear not to have overcome customer perceptions that these units would be impractical due to high cost per use.
The moveable self-contained waterborne sanitation restrooms that are commercially available cannot take advantage of resource opportunities specific to a site, such as alternative water and power sources. For example, the unit manufactured by Joe Welch Companies, Inc. cannot take advantage of available grid power or site supplied water. They cannot be fitted with large capacity tanks or connected to sewage tanks that serve multiple restrooms. Furthermore, the units that are commercially available cannot function in freezing temperatures; they have no variability in architectural design or size; they have no flexibility on the number of fixtures, or the types of fixtures, such as the addition of showers, sinks, or drinking fountains.

SUMMARY

There has long been a need for more pleasant permanent stand-alone toilet facilities in locations not served by standard utilities. This need is apparent from the significant effort that the U.S. Forest service and others have put into making vault toilets more pleasant for users. The SST design features reduce the odors within a vault toilet restroom building. They do not eliminate the foul odors that occur externally to the building in areas that are downwind. Despite the significant efforts of the U.S. Forest Service and others to improve vault toilet restroom buildings, the negative public perception of these restrooms remains. Accordingly, there is, and has been for some time, a significant need for fixed location restrooms that do not have the drawbacks of vault and composting toilet systems in locations without sewer or on-site septic systems.
The present inventor has taken an entirely different approach to filling this need. While the development of remote fixed restroom buildings over the past several decades has been focused on making vault toilet systems bearable for users, and composting toilets practical, the present inventor has shifted his focus to the development of waterborne toilet systems for fixed restroom buildings with embodiments that can work even in remote locations. Accordingly, the fixed location, ultra-low volume flush, sewage-holding vessel restroom systems described herein represent a significant advance in this area of technology that would not have been suggested or made predictable by prior systems.
According to one embodiment, a restroom system is provided. The restroom can include a fixed-in-place restroom building, a flush toilet housed in the restroom building, a water supply system in communication with the flush toilet, and a sewage-holding vessel in communication with the flush toilet. A sewage-holding vessel is a vessel (such as a tank or vault) that is configured to hold sewage effluent so that the sewage effluent can be extracted from the tank and hauled away. A sewage-holding vessel is for holding sewage effluent to be hauled and thus does not include the septic features of a septic tank. The restroom can derive its electricity from on-site resources without connection to a grid power system. Sewage can be received in the flush toilet, and water can be supplied from the water supply system to the flush toilet in an amount less than 1 gallon of water per flush. Sewage effluent can be flushed from the toilet bowl and transported to the sewage-holding vessel, and extracted from the sewage-holding vessel to a sewage hauling vehicle tank. The sewage effluent can then be transported in the sewage hauling vehicle tank to a remote sewage disposal location.
According to another embodiment, a restroom system can include a fixed-in-place restroom building and a flush toilet housed in the restroom building. The toilet can use less than 1 gallon of water per flush. A water supply system can be connected to supply water to the toilet. In addition, a sewage-holding vessel can be in communication with the flush toilet to receive sewage effluent from the flush toilet. The sewage-holding vessel can include an outlet for extracting sewage effluent from the sewage-holding vessel.
According to yet another embodiment, an existing vault or composting toilet restroom building can be retrofitted with one or more flush toilets to produce a flush toilet restroom building. The retrofitting can include replacing vault or composting toilet risers housed in a fixed-in-place restroom building with flush toilets. The flush toilets can be designed to use less than one gallon of water per flush, and can be in communication with a sewage-holding vessel that was previously in communication with the vault or composting toilet risers. An internal or external water supply system can be connected to the flush toilet, and a self-contained or grid power supply system can be connected to the flush toilet restroom system.
This Summary is provided to introduce a selection of concepts in a simplified form. The concepts are further described below in the Detailed Description section. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. The features described herein may be used separately or in combination. For example, many of the features described below, such as the features related to frost protection, may have uses other than in fixed-in-place restroom systems with ultra low volume flush toilets. Similarly, the invention is not limited to implementations that address the particular techniques, tools, environments, disadvantages, or advantages discussed in the Background, the Detailed Description, or the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top sectional site and building plan view of a restroom system for Site #1, with most mechanical room equipment not shown.

FIG. 2 is a sectional view taken along line A-A of FIG. 1, with most mechanical room equipment not shown.

FIG. 3 is a sectional view taken along line B-B of FIG. 1, illustrating mechanical room equipment.

FIG. 4 is a partially cut-away top view of a vault plan for the restroom system of FIG. 1.

FIG. 5 is a schematic wiring diagram illustrating electrical components and connections of the restroom system of FIG. 1.

FIG. 6 is a top site plan view of an alternative restroom system for Site #2.

FIG. 7 is a top building plan view of a restroom building in the restroom system of FIG. 6, with most mechanical room equipment not shown.

FIG. 8 is a sectional view taken along line C-C of FIG. 7, with most mechanical room equipment not shown.

FIG. 9 is a sectional view taken along line D-D of FIG. 7, illustrating mechanical room equipment.

FIG. 10 is a top site plan view of an alternative restroom system for Site #3.

FIG. 11 is a top building and site plan view of an alternative restroom system for Site # 4, with most mechanical room equipment not shown.

FIG. 12 is a sectional view taken along line G-G of FIG. 11, with most mechanical room equipment not shown.

FIG. 13 is a sectional view taken along line H-H of FIG. 11.

FIG. 14 is a sectional view taken along line I-I of FIG. 11, illustrating mechanical room equipment.

FIG. 15 is a schematic wiring diagram illustrating some electrical components and connections of the restroom system of FIG. 11.

FIG. 16 is a flow diagram illustrating general techniques relating to fixed-in-place stand-alone flush restroom systems.

FIG. 17 is a flow diagram illustrating general techniques relating to retrofitting existing restrooms to form fixed-in-place stand-alone flush restroom systems.

The description and drawings may refer to the same or similar features in the same or different drawings with the same reference numbers.

DETAILED DESCRIPTION

I. Fixed Location, Ultra-Low Flush Restroom System Features

Prior fixed-in-place flush restroom buildings have required a water system and either a sewer or septic system. If there is a potential for freezing, building heating is required. Thus, such restrooms have not been used in many remote locations. The described embodiments provide restroom features that allow flush toilet restrooms to operate almost anywhere that has motorized vehicle access. These features can include ultra-low volume flush toilets and sewage holding vessels. The ultra-low volume flush toilets can produce a low amount of sewage effluent to be stored in the holding vessels and hauled away. Such toilets can also use a low amount of water. The restroom systems may also provide freeze protection without the need to heat the restroom buildings. In some embodiments, restroom systems may also contain one or more of the following features:

- waterless urinals;
- devices that prevent sewage spills and overflows;
- water-holding tanks;
- equipment that pressurizes water for flushing toilets;
- equipment that pressurizes air for flushing toilets;
- in-ground tanks, vaults, or basements for containment of water, sewage, or equipment;
- power derived from grid power, solar array(s), wind turbine(s), storage batteries, mini-hydro, on-site combustion generators, or a combination thereof;
- water provided by connection to an existing on-site potable water system; by connection to an on-site irrigation system; by collection of ground water, surface water, or rainwater; by hauled water; or by any combination thereof;
- flue stacks for ventilation;
- mechanical equipment that enhances or controls ventilation;
- systems designed to prevent freezing of the water system;
- maintenance features such as pump-out and fill piping; gauges or indicators that show water levels, sewage levels, and battery charge; and automatic door locks for times that the restroom needs to be closed (i.e. after dark in public parks; when holding vessel is full; when water tank is empty; when electrical power is disrupted; when water pressure is lost; etc.);
- septic tanks that treat sewage prior to hauling;
- porta-potty disposal and washdown sinks, fixtures, and drainboards;
- water conserving faucets and sinks, such as those that turn off automatically after a short period of time;
- water purification devices to remove pathogens from untreated water;
- water conserving showers, such as those that turn off automatically after a short period of time; and
- communal men's and women's rooms equipped with multiple fixtures and with privacy partitions.

In some embodiments, restroom systems may be entirely new constructions. However, in other embodiments, existing restroom buildings such as vault or composting restroom buildings may be converted to fixed location, ultra-low volume flush, sewage holding vessel restroom systems. The restroom systems and restroom buildings may be put to non-residential use in non-residential settings, such as in campgrounds, golf courses, etc.
The fixed location, ultra-low volume flush, sewage holding vessel restroom systems described herein can avoid drawbacks of vault and composting toilet building systems. The described restrooms can be substantially odorless, both internally and externally. They may be implemented without existing water service or connection to an on-site septic system or public sewer, which are used for conventional flush toilet restrooms. They can produce highly conserved sewage effluent that is less likely to have trash and chemicals, and that can often be economically hauled to standard sewage treatment facilities, typically without alteration or dilution. The restrooms described below may be implemented without installing new utility service lines or systems, and they may utilize existing on-site power resources and water resources (supplemented by hauled water if needed).

II. Factors Pointing Away From Fixed Location, Ultra-Low Flush Sewage Holding Vessel Restroom System

Several factors would have pointed those in the fixed location restroom industry away from developing, marketing, or deploying a fixed location, ultra-low volume flush, sewage holding vessel restroom system. Thus, doing so would not have been suggested by or predictable from prior restroom systems. However, the present inventor has made several discoveries, which reveal that—contrary to the accepted wisdom in the industry—fixed location, ultra-low volume flush, sewage holding vessel restroom buildings are feasible and desirable. To understand why those in the industry would have been pointed away from fixed location, ultra-low volume flues, sewage holding vessel restrooms, the following should be considered:

- A. The industry that specializes in the science of self-contained fixed location toilet buildings is largely unaware of developments in mobile ultra-low volume flush toilet technologies.
- B. The industry that specializes in the science of self-contained fixed location toilet buildings would assume that self-contained flush restroom buildings would require hauling copious amounts of sewage effluent and flush water and would therefore be too expensive to be practical.
- C. The industry that specializes in the science of self-contained fixed location toilet buildings (vault and composting) would assume that self-contained flush toilet restroom buildings have significantly higher construction (capital) costs than vault or composting toilet buildings.
- D. The industry that specializes in the science of self-contained fixed location toilet buildings (vault and composting) would assume that a potable water supply would be required for a flush toilet system.
- E. The industry that specializes in the science of self-contained fixed location toilet buildings (vault and composting) would assume that self-contained flush toilet restroom buildings need to be heated to prevent freezing of the water system in locations subject to freezing temperatures during the use season.
- F. Making a self-contained flush toilet restroom building practical and applicable to a variety of site conditions may require many different design solutions, many of which are not intuitive.

These factors and some of the present inventor's discoveries that helped him overcome these factors are discussed below.
A. The industry that specializes in the science of self-contained fixed location toilet buildings is largely unaware of developments in mobile flush toilet technology.
The community that specializes in fixed location restroom buildings deals with a market dominated by campgrounds, parks, and highway rest areas. It is far removed from the community that designs mobile flush toilet systems for RV's, buses, trains, airplanes, and boats; where minimizing water usage has become a science unto itself. Therefore, the fixed location restroom industry has remained unaware of the applications of ultra-low volume toilets and waterless urinals that are durable enough for public use and that can drastically reduce the cost of pumping and hauling sewage.
B. The industry that specializes in the science of self-contained fixed location toilet buildings would assume that self-contained flush restroom buildings would require hauling copious amounts of sewage effluent and flush water and would therefore be too expensive to be practical.
The inventor has discovered that through the use of ultra-low volume flush toilets and waterless urinals the amount of water needed for a flush toilet restroom can be reduced by approximately 90%, and the amount of sewage produced can be reduced by approximately 86%, when compared to standard low flow flush toilets and urinals. Table A and B below compare the amounts of water used and sewage effluent produced by 1000 typical uses where a public restroom building is equipped with 1 quart per flush toilets, such as the Microphor model LF520 toilet, and waterless urinals, instead of standard “low volume flush toilets and urinals.” The Site #1 restroom building illustrated in FIGS. 1-4 and discussed below can have a sewage-holding tank capacity of 2,335 gallons. If this restroom is equipped with one quart per flush toilets, then the capacity of the sewage-holding tank can be 8,876 uses. In some locations this can represent an entire use season, requiring only one pumping per year, which is the maximum time interval recommended for pumping vault toilets.

TABLE A

ESTIMATED SEWAGE GENERATED AND WATER USED
WITH MICROPHOR FLUSH TOILETS (1 quart per flush)
AND WATERLESS URINALS, PER 1000 USES

	vol./
element	use	unit	uses	volume	unit

# 2 (bowel	water	0.375	gallons	200	75	gallons
movement)	waste	0.08	gallons	200	16	gallons
	urine	0.04	gallons	200	8	gallons
# 1 (urine only)	water	0.25	gallons	400	100	gallons
female	urine	0.08	gallons	400	32	gallons
# 1 (urine only)	urine	0.08	gallons	400	32	gallons
male
			TOTAL		16	gallons
			WASTE
			TOTAL		72	gallons
			URINE
			TOTAL		175	gallons
			WATER
			TOTAL		263	gallons
			EFFLUENT

* Table shows a # 2 use requiring more flush water than a # 1 use. This is due to the assumption that # 2 usage will sometimes require more than one flush.

TABLE B

ESTIMATED SEWAGE GENERATED AND WATER USED
WITH STANDARD “LOW VOLUME” FLUSH
TOILETS & URINALS, PER 1000 USES

	vol./
element	use	unit	uses	volume	unit

# 2 (bowel	water	2.4	gallons	200	480	gallons
movement)	waste	0.08	gallons	200	16	gallons
	urine	0.04	gallons	200	8	gallons
# 1 (urine only)	water	1.6	gallons	400	640	gallons
female	urine	0.08	gallons	400	32	gallons
# 1 (urine only)	water	1.6	gallons	400	640	gallons
male	urine	0.08	gallons	400	32	gallons
			TOTAL		16	gallons
			WASTE
			TOTAL		72	gallons
			URINE
			TOTAL		1760	gallons
			WATER
			TOTAL		1848	gallons
			EFFLUENT

* Table shows a # 2 use requiring more flush water than a # 1 use. This is due to the assumption that # 2 usage will sometimes require more than one flush.

In addition, flush toilet effluent is typically significantly less expensive to pump out and dispose of than vault waste. Hauling costs may be further reduced if the flush toilet effluent is hauled to a nearby location served by a sewer manhole or septic drain-field system, which are options not typically available for vault waste. Additionally, the quantities of water delivered by hauling can be reduced or eliminated by using on-site non-potable water, such as rainwater, ground water, surface water, or irrigation water.
C. The industry that specializes in the science of self-contained fixed location toilet buildings would assume that self-contained flush toilet restroom buildings have significantly higher construction (capital) costs than vault toilet buildings.
Vault toilet restroom buildings typically have no mechanical elements. The self-contained restroom buildings described below have ultra-low volume flush toilets involving electrical and mechanical operators and controls. Additionally, they may be equipped with waterless urinals, solar arrays, batteries, water pumps, accumulator tanks, temperature controlled ventilation dampers, water tanks, gauges, controls, etc. Those in the industry would therefore assume that the construction costs for self-contained flush toilet restroom buildings would be higher than restroom buildings equipped with vault toilets.
However, the present inventor has discovered that vault toilet buildings can require more floor space per toilet than the restrooms described below. This is particularly true when the vault toilet buildings are built per SST guidelines, which require separate toilet rooms, flue stacks, vaults, and access manholes for each toilet. Many flush toilets can be accommodated under one roof in some embodiments, such as Site #3 discussed below, creating an economy of scale that can result in lower capital costs per toilet than for vault toilet buildings. Reducing the amount of floor space per toilet can significantly reduce the overall cost because it is believed that the toilet building alone can represent as much as 60% of the capital costs for the ultra-low volume flush toilet buildings described herein. As additional toilets and urinals are added under one roof, the restroom building remains mechanically the same except for the additional flush toilets and urinals. Thus, there is an economy of scale with the restroom systems described herein, with the capital cost per toilet decreasing with the number of toilets installed.
Additionally, the present inventor has discovered that some existing vault toilet buildings can be economically converted to waterborne restroom systems according to embodiments described below, such as Site # 4. Once converted, the vault toilet building can become a restroom building served by ultra-low volume toilets, and possibly with waterless urinals. Converting the existing vault or composting restrooms could be much less expensive than constructing new flush toilet buildings where owners desire this improvement.
D. The industry that specializes in the science of self-contained fixed location toilet buildings (vault and composting) would assume that a potable water supply would be required for a flush toilet system.
Conventional thinking is that public flush toilet buildings require connection to public water systems. In some locations this is not possible or may be very expensive to install and maintain. However, for those embodiments described herein where restrooms are without plumbing fixtures for drinking, bathing, or hand washing, potable water is not required. For those embodiments where plumbing fixtures for drinking, bathing, or hand washing are provided, a non-potable water supply can be used, provided the restroom is equipped with a water purification system that removes pathogens. Thus the embodiments described herein may operate without a potable water supply.
E. The industry that specializes in the science of self-contained fixed location toilet buildings would assume that self-contained flush toilet restroom buildings need to be heated to prevent freezing of the water system in applications subject to freezing temperatures during the use season.
Conventional thinking holds that preventing freezing of the water supply system would require heat produced by grid power, combustion power generation, natural gas heat, or propane heat. In many locations, grid power and natural gas are not available. Combustion power generation and propane heating have several drawbacks. For example, they require gas storage and have environmental, security, cost, and safety issues. However, as described herein, the present inventor has discovered several ways to protect the water supply system from freezing without resorting to conventional heating methods. These methods include controlling and limiting exterior/interior air exchange; capturing ground heat through heat exchanged under the building or through the water vault; circulation of ground conditioned air through the mechanical room and under and around the toilet bowls; and automatic flushing of the toilets when the water in the bowls approaches freezing temperatures.
F. Making a self-contained flush toilet restroom building practical and applicable to virtually any site condition requires many design solutions, many of which are not intuitive.
Those in the fixed-in-place restroom industry would have been deterred from developing self-contained water-borne restroom buildings because of the many issues that would need to be addressed, including water conservation, reducing hauling costs, spill prevention, power supply, mechanical operators and controls, freeze protection, water purification, and pressurizing water. The present inventor has found ways to address these issues in comprehensive designs, as described below with reference to several examples of restroom systems.
The present inventor has discovered that for fixed location flush toilet restroom buildings to be practical in areas not fully served by sewers, potable water, and grid power, several desirable features can be addressed by design. They include minimizing water usage and sewage production and providing on-site sewage effluent storage. The system can also include other features, such as system controls, a building that is essentially odor free inside and outside, and safeguards to prevent sewage spills. Components and sub-systems of the described system can be included to address the design features listed above. These components and sub-systems can include ultra-low volume flush toilets (using less than 1 gallon per flush), leak resistant sewage tanks or vaults, and mechanical and electrical systems and controls. These flush toilet features have not previously been suggested or otherwise made predictable for fixed-in-place restrooms. Instead, the resources that have gone into improving fixed restrooms in remote locations over the past several decades have focused on improving vault and/or composting toilet restroom systems.

III. Restroom System Embodiments at Various Sites

The described restroom system embodiments may be utilized in combinations that are customized for the specific site conditions and/or the needs of specific users or site owners. Generally, the combination of embodiments may capitalize on the existing assets for each site. For example, if a potable water system is not available, then the best alternative water source could be hauled water or an on-site source such as ground water, surface water, irrigation water, or rainwater, or a combination thereof. If grid power is not available at the site, then the marginal power needs of the restroom could be supplied by solar array(s), or by storage batteries, which are periodically rotated with new batteries or batteries that have been charged off-site. If frost protection is desirable at a particular location, it can be provided without heating the building.
Since there are many possible combinations of embodiments of the described restroom system, and many possible floor plans, it is not practical to include drawings of all possible options. The embodiments described below will make it apparent to persons skilled in this area of technology that they may implement different combinations of features, depending on the available resources at the site. The drawings and description below demonstrate that restroom buildings as described herein can be configured to provide affordable and practical service in locations where the current accepted wisdom in this technology area would suggest that a flush toilet restroom is impractical, and that vault toilet or composting toilet restroom buildings are the only reasonable option. To this end, details are provided herein that address embodiments for four different site conditions.
It should be noted that the subject matter defined in the appended claims is not necessarily limited to the benefits described herein or the details of particular embodiments. A particular implementation of the invention may provide all, some, or none of the benefits described herein. Although operations for the various techniques may be described herein in a particular, sequential order for the sake of presentation, it should be understood that this manner of description encompasses rearrangements in the order of operations, unless a particular ordering is required. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Techniques described herein with reference to flowcharts may be used with one or more of the systems described herein and/or with one or more other systems. Moreover, for the sake of simplicity, flowcharts may not show the various ways in which particular techniques can be used in conjunction with other techniques.

A. Site#1

This hypothetical location has no available sewer or septic system, no grid power, and no on-site water source. The location may be subjected to periodic sub-freezing temperatures during the use season. It does have good solar exposure and ample precipitation. In this case, the configuration of the restroom building chosen by the designer and owner might be as depicted in FIGS. 1-5.
The illustrated restroom system (100) can include a building (102) with approximately 97 square feet of interior space, although many different configurations and/or sizes of restroom buildings could be used. The building (102) can include a floor (104), a front exterior wall (106), a pair of side exterior walls (108), a rear exterior wall (110), and a roof (112).
The building (102) can include two toilet rooms (120) that can be mirror images of each other, however in this example they are not equipped the same. Each toilet room (120) can be defined by the rear exterior wall (110), a side exterior wall (108), the front exterior wall (106), and a side interior wall (122) that extends from the front exterior wall (106) back to the rear exterior wall (110), and between the floor (104) and the roof (112). The toilet rooms (120) can each be equipped with standard grab bars (124) and may have a turning radius (126) sufficient to accommodate a wheelchair, such as a 5 foot turning radius.
The building (102) can also include a mechanical room (128) between the two toilet rooms (120). The mechanical room (128) can be defined by the side interior walls (122) and the front and rear exterior walls (106, 110). The mechanical room (128) can extend from the floor (104) to a mechanical room ceiling (132), which can divide the mechanical room (128) from a mechanical room attic (134). The mechanical room attic (134) can be located directly above the mechanical room (128) and can be defined by the front and rear exterior walls (106 and 110), the side interior walls (122), the mechanical room ceiling (132), and the roof (112). The building (102) can also include toilet room doors (140) and a mechanical room door (142) in the front exterior wall (106).
Each toilet room (120) can house an ultra-low volume flush toilet (150) located adjacent to the interior side wall (122) of the toilet room (120). Toilet operators or controls (152), which are devices used to operate the toilet (150), can be incorporated into the toilet (150) and/or located near to or remotely from the toilet (150). Such operators (152) can include a control system; a connection to an electric power supply system; and a connection to a water supply system. The toilets can be any ultra-low volume flush toilets (i.e., toilets using less than one gallon of water per flush), such as a flush toilet using less than about 0.75 gallons per flush or less than about 0.5 gallons per flush. In one embodiment, the toilet (150) can be a Microphor model LF320 stainless steel toilet available from Microphor of Willits, California, which can be set to use between 0.25 and 0.5 gallons per flush. In one embodiment, the operators (152) can be standard operators also available from Microphor for the LF320 model. These operators (152) can be configured in a conventional manner according to standard techniques, such as those set forth in installation instructions from Microphor. One toilet room (120) is shown equipped with a sink (153); a paper towel dispenser (154); a waste container (155); and a urinal (156) such as the waterless urinals available from Waterless Co. under the name Del Mar model 2901. The waterless urinals (156) can be installed and configured in a conventional manner, per the manufacturer's instructions from Waterless Co.
The restroom system (100) also includes a sewage storage system (158), which can include one or more sewage-holding vaults or tanks (160). Holding vessels, such as the holding vaults (160) hold sewage effluent to be hauled away, but the vessels do not include septic treatment features within the vessel. However, in some embodiments sewage effluent may receive primary treatment by passage through a septic tank or other septic treatment device before being removed by hauling. In the illustrated example, the sewage storage system (158) includes one subterranean sewage-holding vault (160) for each toilet room (120), with the vault positioned beneath the rear portion of the associated toilet room (120). Each toilet (150) and urinal (156) can be configured to drain into the associated sewage-holding vault (160) so that the vault (160) receives the sewage effluent from that associated toilet room (120). Each sewage-holding vault (160) can be accessed through a vapor-tight cover (161) of a manhole in the sewage-holding vault (160). Alternatively, the restroom system (100) could include just one sewage-holding vault (160), and it could be located somewhere other than beneath the building (102).
The sewage-holding vault (160) can be a subterranean precast concrete sewage-holding vault (160), and can be equipped with an impermeable liner or coating (162) to seal the vault. The sewage storage system (158) can also include standard sewage pump-out piping (164) that is configured to mate with sewage pump-out equipment associated with a sewage transportation vehicle, such as by having a standard quick-connect feature. Each sewage-holding vault (160) can be vented by a small vertical pipe (166) that extends up from the sewage-holding vault (160) and through the roof (112) of the building (102).
Each sewage-holding vault (160) can be equipped with one or more standard float switches to alert operators and/or disable the flushing system if the sewage-holding vault (160) becomes too full. For example, each sewage-holding vault (160) can include a float switch or level sensor (167) connected to a device (168) to alert an operator that the sewage-holding vault (160) should be pumped out soon. This device (168) can be an indicator light, a level indicating gauge, or a signal transmitter (168). Each sewage-holding vault (160) can also include a higher level float switch (169) that can activate an electric lock on the toilet room doors (140) and/or shut down at the water supply system (170), which is part of the restroom system (100), before the effluent in the sewage-holding vault (160) can overflow. These float switches and the corresponding control circuitry will be described in more detail below.
The water supply system (170) can supply pressurized water to the toilets (150). The water supply system (170) can include a water storage vault (172) beneath each of the toilet rooms (120), such as a subterranean water storage vault (172) which can have an impermeable liner (173). The building can be equipped with a rainwater collection system (174) which can include standard rain gutters (176), as well as standard downspouts (178) leading into the water storage vaults (172). The water supply system (170) can also include water fill piping (180), which can be standard piping for receiving additional water to supplement collected rainwater. For example, the water fill piping (180) can be configured to connect to a water-hauling vehicle. The water supply system (170) can also include a water pressurization system (182) that includes a water pump (184) connected to draw water from the water storage vault (172) and feed it into an accumulator tank (186), which is connected to the toilets (150) and sink (153) to supply pressurized water. The water pump (184) can be a standard water pressurizing pump, such as a “Classic 2088” water pump available from Shurflo, and the accumulator tank (186) can be a standard tank, such as a 3400-002 tank available from Shurflo. The water system can be equipped with a water purification system (188), such as the “Water-fixer, model 500” to deliver pathogen free water to the sink (153). In addition, the water storage vaults (172) can have block-outs (190) high on their side walls that allow excessive rainwater or filling water inflows to spill out of the vault, thus preventing overfilling of the water storage vaults (172). The water supply system (170) also includes water lines (192) that connect the various other components of the water supply system.
The restroom system (100) can also include a power supply system (210) that includes a solar panel (212), such as the model GEPV-50 solar panel available from General Electric. The power supply system (210) can also include a controller (214), such as the 12 volt, 15 amp controller equipped with a digital voltage meter available from Prostar. The power supply system can also include one or more standard storage batteries (216), such as two MK model 8G27 storage batteries. The restroom system (100) could have as few as one battery, or several batteries, depending on what the owner wants, as well as the electrical demands and the power source. The storage batteries (216) can be connected in a conventional manner to be recharged by the solar panel (212), to supply the power needs of the restroom system (100). The solar panel (212) can be mounted on top of a flue stack (218) that extends up along the rear exterior wall (110). For example, the solar panel (212) can be mounted with a rotatable base (220), which allows a user to pivot the solar panel (212) to face in a desired direction (such as south when in the northern hemisphere) no matter what the building orientation is.
The restroom system (100) can include a frost protection system (230). The frost protection system (230) can include one or more of several components to protect the restroom system (100) from freezing temperatures. For example, the frost protection system (230) can include building insulation in the exterior walls (106, 108, and 110) and the roof (112); insulation around plumbing equipment such as the water pump (184) and the accumulator tank (186); and/or water lines (192) that do not break when frozen.
During use, the ventilation for the restroom building (102) can be passively enhanced by the influence of the flue stack (218). The flue stack (218) can be vented through the grill (234) into the mechanical room attic (134). As air flows over the top of the flue stack (218), the venturi effect can create negative pressure in the stack (218), which in turn creates negative pressure in the unducted portion of the mechanical room attic (134). Relief air into the mechanical room attic (134) can be supplied from the toilet rooms (120) via the return ventilation grills (236). Relief air can be supplied into the toilet rooms (120) from the outside as described below. Thus, air can be circulated to continually provide fresh air to the toilet rooms (120), so long as there is air flowing over the flue stack (218).
In this example for site #1, the frost protection system (230) can include a passive heating and ventilation system (232) that controls air into the building (102) and collects energy from the earth when required. When outside temperatures are above freezing, fresh unconditioned air from outside can flow through the building (102) through a series of grills and ducts. When outside sub-freezing temperatures occur the air flow can be limited to air with temperatures that have been moderated by energy absorbed from the earth.
When outside temperatures are above freezing, air flow can be sequenced as follows: air is drafted up the flue stack (218) having flowed from the mechanical room attic (134) through a flue-to-attic grill (234) in the rear exterior wall (110); having flowed from the toilet rooms (120) to the mechanical room attic (134) through a pair of ventilation grills (236) located in the side interior walls (122); having flowed from the outside to the toilet rooms (120) through ventilation grills (238) and supply ducts (240) in the side interior walls (122) and through a mechanically controlled damper (250) location high on the front exterior wall (106).
When outside temperatures drop below the set point of an external thermostat switch (252) the mechanically activated damper (250), such as model CD50 damper available from Ruskin, can be activated and closed. When this happens, unconditioned outside air no longer flows through the building (102) according to the airflow described above. When the damper (250) is closed air flow can be sequenced as follows: air is drafted up the flue stack (218) having flowed from the mechanical room attic (134) through a flue-to-attic grill (234) in the rear exterior wall (110); having flowed from the toilet rooms (120) to the mechanical room attic (134) through a pair of ventilation grills (236) located in the side interior walls (122); having flowed from the mechanical room (128) through ventilation openings (260) in each toilet's (150) metal housing and through the interior space between each toilet's (150) metal outer housing and inner metal toilet bowl and through the mechanical access hole (262) at the back of each toilet (150) in the mechanical room wall (122); having flowed from the outside through floor grates (268) in the mechanical room floor (104) through exhaust ventilation chases (270) cast in the walls of the water storage vaults (172) through a serpentine route through the plenums (276) beneath the bottom of the water storage vaults (172) through intake ventilation chases (280) cast in the walls of the water storage vaults (170) through intake grates (282) that are exposed to the outside air. This routing can provide conditioned relief air that is influenced by the ground temperatures found in and under the water storage vaults. As this air travels through the mechanical room (128) and through the space under and around the bowls of the toilets (150) it can help keep the toilets (150) and the components of the water supply system (170) in the mechanical room (128) from freezing.
The plenum (276) can be created under the water vault liner (173) by framing (286), such as wood or metal framing, on a concrete floor (288) of the water storage vault (172). A plate (292), such as a steel plate, can be located on top of this framing, and the bottom of the tank liner (173) can rest on this horizontal plate (292). The horizontal plate (292) can extend from wall to wall in both directions. Each vertical chase (270 and 280) can be enclosed by a vertical plate (296), such as a metal plate, covering the exposed vertical face of the chase (270) extending downward from the respective grates (268, 282) to the top of the plenum (276). The framing (286) under the horizontal plate can direct air flowing through the plenum (276), forcing the air to travel a serpentine route. This serpentine route can increase mixing and contact time of the air with the metal plate (292) above and the concrete vault floor (288) below. During freezing weather this process can condition the air by raising its temperature. A plenum drain (298) can be located in the vault floor (288) near the center of this plenum space (276) to allow any condensation to seep out. A similar plenum and venting system can be installed in the sewage storage tank to increase air flow, but it is not illustrated in the drawings. This type of venting system (232) can be useful aside from its use with the described restroom systems. For example, this type of venting system could be used for general heating and cooling of a general purpose building. Referring to FIG. 5, the electrical components of the restroom system (100) are illustrated in a schematic wiring diagram. As can be seen, the solar array or panel (212) and the batteries (216) can be connected by positive and negative leads to the battery charge controller (214), which regulates the charging of the batteries (216) by the solar panel (212) and the output of power from the batteries (216) to the other electrical components. The batteries (216) can output 12 volt power, although other voltages could also be used, depending on the batteries and the needs of the other electrical components. If the electrical components have different voltage needs, then standard power converters can be used, as needed.
Power to a damper controller (310), which controls the damper (250), can be routed through a standard 12 volt DC-to-24 volt DC power converter (308), such as a Solar Converter Inc, model EQ122420 converter, if the damper controller is a 24 volt device. An exterior mounted thermostat switch (252), such as a standard thermostat switch found in a typical RV, can be mounted on the exterior rear wall (110) or some other place outside the building (102), and can be wired to close the circuit and power the damper actuator or controller (310), such as a Belimo model TF24 actuator, to close the damper (250) when the outside temperature reaches a predetermined low set temperature. The thermostat switch (252) can open the circuit to allow the damper (250) to open when the outside temperature reaches a predetermined high set temperature.
The lower-level alert float switch (168) in the sewage-holding vault (160) can be wired to close a circuit to power an indicator light or gauge (320) when the level of the sewage effluent in the sewage-holding vault (160) is at or above the alert float switch (168). Thus, the alert float switch (168) and the indicator light or gauge (320) can indicate to maintenance personnel that sewage effluent should be pumped out of the sewage-holding vault (160). The higher level float switch (169) can be wired to open a circuit to shut off power to the water pump (184) if the level of the sewage effluent in the sewage-holding vault is at or above the level of the shut-off float switch (169). In addition to, or instead of, shutting off power to the water pump (184), the shut-off float switch (169) can be wired to open a circuit to shut off power to an electric strike (324) for the associated toilet room door (140), thereby locking the toilet room door (140). Thus, the shut-off float switch (169) can shut off the water supply system (170) and/or lock the toilet room door (140) to keep the sewage-holding vault (160) from overflowing. Because the electric strike (324) is unlocked when it has power and locked when it has no power, the toilet room doors (140) will also be locked if the overall power supply system fails. As an alternative to shutting off a water pump, the shut-off float switch (169) could actuate a valve, such as a solenoid valve, to shut off the water supply system. For example, this could be done in embodiments where there is no water pump in the water supply system.
Power can also be supplied from the batteries (216) to the toilet controls (152), which control the operation of the toilets (150), and to an air compressor (330), if such an air compressor is used to supply pressurized air to the toilets (150).
The restroom system (100) and the other restroom systems discussed below can be constructed according to conventional building techniques, unless otherwise noted. Standard lighting, windows, and/or skylights may be added. Additionally, all piping, wiring and other building materials can be conventional commercially available materials.

B. Site#2

Referring to FIGS. 6-9, Site #2 is located on a golf course where the closest available sewer line is located at the clubhouse, which is a significant distance away from the site. The site is not served by road access, but is adjacent to a golf cart path (400), which is not designed for heavy trucks, such as those normally used to pump toilet and septic systems. There is no nearby potable water, but there is a non-potable buried irrigation water main (402) near the golf cart path (400). The restroom system (410) may be exposed to periodic freezing temperatures. The site does not have good solar exposure.
The restroom system (410) can include a restroom building (412) with approximately 80 square feet of interior space. The building (412) can include a floor (414), a front exterior wall (416), a pair of side exterior walls (418), a rear exterior wall (420), and a roof (422). The building (412) can include two toilet rooms (430) that can be mirror images of each other. Each toilet room (430) can be defined by the rear exterior wall (420), a side exterior wall (418), the front exterior wall (416) including a toilet room door (431), and a side interior wall (432) that extends from the front exterior wall (416) back to the rear exterior wall (420), and between the floor (414) and the roof (422). The toilet rooms (430) can each be equipped with standard grab bars (434). Even though the toilet rooms do not have a 5-foot wheelchair turning radius, they can meet federal accessibility standards.
The building (412) can also include a mechanical room (438) between the two toilet rooms (430). The mechanical room (438) can be defined by the side interior walls (432) and the front and rear exterior walls (416, 420) and an access door (440). The mechanical room (438) can extend from the floor (414) to a mechanical room ceiling (442), which divides the mechanical room (438) from a mechanical room attic (444). The mechanical room attic (444) can be located directly above the mechanical room (438) and can be defined by the front and rear exterior walls (416 and 420), the side interior walls (432), the mechanical room ceiling (442), and the roof (422).
The restroom building (412) can be equipped with ultra-low volume flush toilets (450) located adjacent to the interior side wall (432) of each toilet room (430). Toilet operators (452), which are devices used to operate the toilets (450), can be incorporated into the toilets (450) and/or located near to or remotely from the toilets (450). Such operators (452) can include a control system; a connection to an electric power supply system; a connection to a water supply system; and a connection to a pressurized air system, such as an air compressor. In this embodiment, the toilets (450) can be Microphor model LF520 toilets available from Microphor of Willits, Calif., and the operators (452) can be standard operators also available from Microphor for the LF520 model. These operators (452) can be configured in a conventional manner according to standard techniques, such as those set forth in installation instructions from Microphor. Each toilet room (430) can also house a urinal (456), such as the waterless urinals available from Waterless Co. under the name Kalarahi model 2003. The waterless urinals (456) can be installed and configured in a conventional manner, such as by following instructions from Waterless Co. The LF520 toilet can use as little as one quart per flush, and it can macerate the sewage for easier pumping. The LF520 requires pressurized air, and it is fitted with pressurized air fittings, which can be served by a small air compressor (457), such as the Microphor model 5000 air compressor.
The restroom system (410) also includes a sewage storage system (458). In the illustrated example, the restroom building (412) does not have a vault beneath it. Instead, the sewage storage system (458) includes a sewage-holding tank (460) located near the golf cart path (400). The sewage-holding tank (460) can be equipped with a quick-connect pump-out pipe (462). The sewage-holding tank (460) can be equipped with one or more standard float switches to alert operators and/or disable the system if the sewage-holding tank (460) becomes too full. For example, the sewage-holding tank (460) can include an alert light float switch (not shown) at one level to alert an operator that the sewage-holding tank (460) should be pumped out soon, such as by activating an indicator light (461). The sewage tank (460) can also include a shut-off float switch (not shown) at a higher level to shut down at least a portion of a water supply system (discussed below), which is part of the restroom system (410), if the sewage level in the sewage-holding vault (460) is too high. These float switches and the corresponding control wiring (466) can be the same as for Site 1, which is described above with reference to FIGS. 1-5, except that the wiring (466) extends between the sewage holding tank (460) and the restroom building (412). The sewage-holding tank (460) can be accessed by opening an essentially vapor-proof manhole cover (470).
Sewage can flow to the holding tank (460) through a buried sewer line (472). Toilet drains (473) and urinal drains (474) can connect to the buried sewer line to empty urine and sewage effluent from the toilets (450) and urinals (456) into the sewer line (472). At the end of the sewer line (472) proximal to the restroom building (412), a vertical vent (475) can extend up from the sewer line (472) and through the building roof (422). A cleanout riser (476) can also extend up from the sewer line (472) at the end proximal to the restroom building (412). The slope and other design features of the sewer line (472) can be according to known methods, and can be done to comply with local regulations.
Sewage effluent can be removed from the sewage-holding tank (460) using a small trailer (not shown) equipped with commercially available equipment, including a plastic holding tank for sewage; an electric pump; a small electric generator; and a pump-out hose with a quick connect fitting. This trailer could be towed by an ATV, light truck, or tractor to a sewer manhole at the clubhouse or to a nearby sewage treatment facility, where it could be emptied. This trailer and its equipment are not described in detail herein because standard equipment can be used.
The water supply system (480) of the restroom system (410) can include a standard valve box (482) installed on the irrigation main (402), and a main restroom water supply line (484) running from the valve box (482) to the restroom building (412). The main restroom water supply line (484) can be connected to the toilets (450) with standard restroom building water supply lines (486) and other standard plumbing components and techniques.
The restroom system (410) can also include a power supply system (510). Because the site has poor solar exposure and no convenient connections to grid power, the power supply system (510) can include two banks of batteries (514) in the mechanical room (438). Each battery can be a standard storage battery, such as an MK model 8G27 battery. Each bank can have one or more batteries. For example, each bank can include two batteries connected in parallel, for a total of four batteries—with two in use, and two spares. One bank at a time can be connected to the restroom building electrical system and to a voltage meter (516). When the voltage is sufficiently depleted in one bank of batteries, a person can connect the second bank to the electrical system and the voltage meter (516). The two partially depleted batteries can be transported to the golf course maintenance facility for connection to a battery charger. Once recharged, they can be returned to the restroom to serve as the spare battery bank.
The restroom system (410) can also include a frost protection system (530). The frost protection system (530) can include one or more of several components to protect the restroom system (410) from freezing temperatures. For example, the frost protection system (530) can include building insulation (531) in the exterior walls (416, 418, and 420) and the roof (422); insulation around plumbing equipment; and/or water lines (486) that do not break when frozen.
As another example, the frost protection system (530) can include a passive ventilation system that brings air into the building (412) using ventilation air with temperatures moderated through heat exchanged from the earth below the building (412) circulated as follows: air is drafted up the flue stack (533) having flowed from the mechanical room attic (444) through a flue-to-attic grill (534) in the rear exterior wall (420); having flowed from the toilet rooms (430) to the mechanical room attic (444) through a pair of ventilation grills (536) located in the side interior walls (432); having flowed from the mechanical room (438) to the toilet rooms (430) through ventilation openings (560) in each toilet's (450) metal housing and through the interior space between each toilet's (450) metal outer housing and inner metal toilet bowl and through the mechanical access hole (562) at the back of each toilet (450) in the mechanical room wall (432); having flowed from the outside through floor grates (568) in the restroom's floor slab (414) through a ventilation pipe manifold (570) in the ground below the building (412). The ventilation pipe manifold (570) can be used if there is no water tank below the building to transfer earth temperatures to the supply air, as there is at Site #1. The ventilation pipe manifold (570) can be perforated to allow moisture to escape, such as by draining through perforations in the bottom of the manifold pipe (570).
During use, the ventilation system (532) at Site #2 can work the same as the ventilation system (232) described above with reference to Site #1, except that the intake air can flow through the buried ventilation pipe manifold (570), rather than through a plenum beneath a water vault, and the damper and the associated ductwork, grills, and activator can be omitted.
The electrical components for the restroom system (410) at Site #2 can be similar to the electrical components described above for restroom system (100) at Site #1, with reference to FIG. 5.

C. Site#3

Referring to FIG. 10, Site #3 is a lakeside day-use county park in a remote location. Site, environmental, and soil conditions make the installation of an on-site septic drain field impractical. However, there is a good site for a septic drain field on county land a mile away. The county wishes to construct two restroom buildings located near an access road (600). Each building is to have a men's and women's restroom with multiple stalls and wash sinks. There is a nearby spring (604) that can provide adequate flush water and has enough elevation to supply the pressure head needed to flush the toilets. (Water could have been supplied by a submersible pump placed in the lake, but the spring source was considered the better option in this particular circumstance.) Both preferred restroom locations have large trees that inhibit the use of solar panels on the buildings. The climate is mild during the use season and freezing is not an issue. The water in the system will be drained during the winter months.
Considering these desired features and site conditions, a restroom system (610) can include two similar restroom buildings (612). The restroom buildings (612) can each have a men's side (614) and a women's side (616), and each can house multiple ultra-low volume flush toilets (618) and urinals (620), as well as sinks (622) and an external cold water shower (624). The toilets (618) and urinals (620) can be the same as the toilets and urinals discussed above with reference to Site #1 and/or Site #2. The restroom buildings can be constructed according to standard building construction techniques.
The restroom system (610) can include a water supply system (630), which can include buried water lines (632) running from a collection box located at the spring (604) to the restroom buildings (612), and a filtered water purification system such as a Pentek CBC-20 (not shown). The restroom system (610) can also include a power supply system (640) that includes a solar collector (642), including a standard solar array and a mast located near the access road (600) where there is good solar exposure. The power supply system (640) can also include buried electrical cables (644) connected to the solar collector (642) and to the restroom buildings (612) in a conventional manner.
In addition, the restroom system (610) includes a sewage storage system (650). The sewage storage system (650) can include buried sewer lines (652) extending from the restroom buildings (612) to a junction manhole (654), and from the junction manhole (654) to a single large sewage-holding tank (656) located near the road (600) where there is sufficient drop from the restroom buildings (612) to the holding tank (656) for the sewage effluent to flow by the force of gravity through the sewer lines (652). The holding tank (656) can be equipped with an access cover (660) and a pump-out pipe (662).
Because freezing is not an issue at this site during the use season, ventilation into the toilet rooms and mechanical room can be provided by standard site proof wall and door grills (not shown). The restrooms can be locked at dusk so that no building lighting is needed.
The electrical components for the restroom system (610) at Site #3 can be similar to the electrical components described above for the restroom system (100) at Site #1, with reference to FIG. 5. However, one electrical system can power the indicator light and toilet controls in both restroom buildings (612), and there is no need for a thermostat switch, water pump, or a damper controller. An upper shut-off float switch (not shown) can prompt a valve actuator, such as a solenoid, to shut off water to the toilets (618), such as by shutting off water to the entire buildings (612), if the sewage-holding tank (656) gets too full.

D. Site #

4

Site # 4 had an existing precast concrete vault toilet restroom building originally manufactured by CXT Inc., model “Double Cascadian with Chase”, which has approximately 96 square feet of interior space and is located at a site with good solar exposure and adequate rainfall. These CXT units include four buried precast concrete vaults placed directly under the precast concrete building unit. The CXT units have two identical vaults for sewage holding. The other two vaults are empty and unused, but are an appropriate size to serve as water holding vaults.
FIGS. 11-15 show the details of a restroom system (800) formed by retrofitting a CXT vault toilet restroom building. Retrofitting could also be done with other restroom buildings, such as other CXT buildings or other non-CXT vault or composting toilet buildings. The finished restroom system (800) will be described first, and a retrofitting technique will be described second.
The illustrated restroom system (800) can include a building (802) with about 96 square feet of interior space, although many different configurations and/or sizes of restroom buildings could be retrofitted. The building (802) can include a floor (804), a front exterior wall (806), a pair of side exterior walls (808), a rear exterior wall (810), and a roof (812).
The building (802) can include two toilet rooms (820) that can be mirror images of each other. Each toilet room (820) can be defined by the rear exterior wall (810); a side exterior wall (808); the front exterior wall (806); a side interior wall (822), which extends from the front exterior wall (806) back to the rear exterior wall (810) and between the floor (804) and the roof (812). The toilet rooms (820) can each be equipped with standard grab bars (824).
The building (802) can also include a mechanical room (828) between the two toilet rooms (820). The mechanical room (828) can be defined by the side interior walls (822) and the front and rear exterior walls (806, 810). The mechanical room (828) can extend from the floor (804) to a mechanical room ceiling (832), which divides the mechanical room (828) from a mechanical room attic (834). The mechanical room attic (834) can be located directly above the mechanical room (828).
The building (802) can also include toilet room doors (840) in the front exterior wall (806) and a mechanical room door (842) in the rear exterior wall (810). In addition, the building (802) can include ceiling insulation (844) in the mechanical room ceiling (832), as well as mechanical room wall insulation (846) on the side interior walls (822) in the mechanical room (828).
Openings in the floor (804) for the original vault toilet risers can be covered with metal plates (848), equipped with sealed openings to accommodate the septic pipes exiting the bottom of each toilet (850). As an alternative these existing floor opening could be filled in with concrete plugs. Each toilet room (820) can house an ultra-low volume flush toilet (850) located adjacent to the interior side wall (822) of the toilet room (820). Toilet operators or controls (852) can be incorporated into the toilets (850) and/or located near to or remotely from the toilets (850). Such operators (852) can include a control system; a connection to an electric power supply system; and a connection to a water supply system. In this embodiment, the toilets (850) can be Microphor model LF320 toilets available from Microphor of Willits, Calif., and the operators (852) can be standard operators also available from Microphor for the LF320 model. These operators (852) can be configured in a conventional manner according to standard techniques, such as those set forth in installation instructions from Microphor.
Water lines can extend from each toilet (850) and through an access hole (854) located behind each toilet (850) in the associated side interior wall (822) into the mechanical room (828). Each toilet room (820) can also house a urinal (856), such as the waterless urinals available from Waterless Co. under the name Kalarahi model 2003. The waterless urinals (856) can be installed and configured in a conventional manner, such as by following instructions from Waterless Co. The LF320 toilet can use as little as one quart per flush.
The restroom system (800) also includes a sewage storage system (858), which can include one or more sewage-holding vaults (860). In the illustrated example, the sewage storage system (858) includes one existing subterranean sewage-holding vault (860) for each toilet room (820), with the vault positioned beneath the rear portion of the associated toilet room (820). Each toilet (850) and urinal (856) can be configured to drain into the associated sewage-holding vault (860) so that the vault (860) receives the sewage effluent from that associated toilet room (820). Alternatively, the restroom system (800) could include just one sewage-holding vault (860), and it could be located somewhere other than beneath the building (802).
Each sewage-holding vault (860) can be a subterranean precast concrete sewage-holding vault (860), which may or may not be equipped with a plastic liner (862) to seal the vault. A sewage-holding vault access cover (863) can be opened to provide access to each sewage-holding vault (860). The sewage storage system (858) can also include standard sewage pump-out piping (864) that is configured to mate with sewage pump-out equipment associated with a sewage transportation vehicle. Each sewage-holding vault (860) can be vented by a small vertical pipe (865) that extends up from the sewage-holding vault (860) and through the roof (812) of the building (802). A toilet drain (866) can extend down from each toilet (850) to the corresponding sewage-holding vault (860), and a urinal drain (867) can extend down from each urinal (856) to the corresponding sewage-holding vault (860).
Each sewage-holding vault (860) can be equipped with one or more standard float switches to alert operators and/or disable the system if the sewage-holding vault (860) becomes too full. For example, each sewage-holding vault (860) can include an alert float switch (868) at one level to alert an operator that the sewage-holding vault (860) should be pumped out soon. Each sewage-holding vault (860) can also include a shut-off float switch (869) at a higher level to shut down at least a portion of a water supply system (870), which is part of the restroom system (800), if the sewage level in the sewage-holding vault (860) is too high. These float switches and the corresponding control circuitry can be similar to the float switches and circuitry described above with reference to Site #1.
The water supply system (870) can supply pressurized water to the toilets (850). The water supply system (870) can include water storage vaults (872) beneath each of the toilet rooms (820), such as the existing subterranean water storage vaults (872) which may be equipped with an impermeable liner or coating (873). A rainwater collection system (874) can include standard rain gutters (876), as well as standard downspouts (878) leading into the water storage vaults (872). The water supply system (870) can also include water fill piping (880), which can be standard piping for receiving additional water to supplement collected rainwater. For example, the water fill piping (880) can be configured to connect to a water hauling vehicle.
The water supply system (870) can also include a water pressurization system (882) that includes a water pump (884) that is connected to draw water from the water storage vault (872) and feed it into an accumulator tank (886), which is connected to the toilets (850) to supply pressurized water to the toilets (850). The water pump can be a standard water pressurizing pump, such as a “Classic 2088” water pump available from Shurflo, and the accumulator tank can be a standard tank, such as a 3400-002 tank available from Shurflo.
In addition, the water storage vaults (872) can have drains (890) high on their side walls that allow excessive rainwater or filling water inflows to spill out of the vault, thus preventing overfilling of the water storage vault (872). The drains (890) can extend through the same holes in the water storage vault (872) through which the downspouts (878) enter the water storage vault (872). The water supply system (870) also includes water lines (892) that connect the various other components of the water supply system.
The restroom system (800) can also include a power supply system (910) that includes a solar panel (912), such as the model GEPV-50 solar panel available from General Electric. The power supply system can also include a controller (914), such as the 12 volt, 15 amp controller equipped with a digital voltage meter available from Prostar. The power supply system can also include one or more standard storage batteries (916), such as two MK model 8G27 storage batteries. The storage batteries (916) can be connected to be recharged by the solar panel (912), and to supply the power needs of the restroom system (800) in a conventional manner. The solar panel (912) can be mounted on top of a flue stack (918) that extends up along the rear exterior wall (810). For example, the solar panel (912) can be mounted with a rotatable base (920), which allows a user to pivot the solar panel (912) to face in a desired direction (such as south when in the northern hemisphere) no matter what the building orientation is.
The restroom system (800) can include a frost protection system (930). The frost protection system (930) can include one or more of several components to protect the restroom system (800) from freezing temperatures. For example, the frost protection system (930) can include building insulation (844, 846) attached to the mechanical room walls (822) and ceiling (832); insulation around plumbing equipment such as the water pump (884) and the accumulator tank (886); and/or water lines (892) that do not break when frozen.
As another example, the frost protection system (930) can include a ventilation system (932) that controls the circulation of air into the building (802). This ventilation system (932) can include the flue stacks (918), which are vented into the toilet rooms (820) through flue-to-toilet room grills (934) in the rear exterior wall (810), existing vents in the exterior walls (935), ventilation grills (936) located in the metal bases of the toilets (850), floor grates (937) in the mechanical room floor (804), and the rain collection downspouts (878).
During use, the ventilation for the restroom building (802) can be passively enhanced by the influence of the wind blowing over the opening of the flue stack (918) due to the venturi effect which can create negative pressure in the stack (918). As interior air exits the stack (918) makeup air from the interior of the building (802) flows through the associated flue-to-toilet room grill (934); having flowed from the toilet rooms (820); having flowed from the mechanical room (828) through ventilation openings (936) in each toilet's (850) metal housing and through the interior spaces between each toilet's (850) metal base exterior and the inner metal toilet bowl and through the mechanical access hole (854) at the back of each toilet (850) in the mechanical room wall (822); having flowed from the outside through floor grates (937) in the restroom's floor slab (804); having flowed through the air space above the water in the water storage vault (872); having flowed through the building's rain down spouts (878). Outside air can also flow into the toilet rooms (820) through the existing vents (935) located at the bottom of the side and back exterior walls (808, 810). These vents can be retrofitted with bug screens or filters to inhibit airflow enough that airflow priority is always given to the air exiting the base of the toilets having traveled a path of lesser resistance and having been conditioned by the influence of ground temperatures surrounding the in-ground water storage vault.
In addition, when the temperature of some point within the building (802), such as the water within the toilet bowls falls below a set point, the toilets (850) can automatically flush to replace the water in the toilet bowls with warmer water from the water storage vault (872). This automatic flushing feature will be described more below.
The electrical components for the restroom system (800) at Site # 4 can be basically the same as the electrical components described above for restroom system (100) at Site #1, with reference to FIG. 5. However, there is no 12 VDC to 24 VDC Converter (308), or Vent Damper Controller (310), or Air Compressor (330).
Referring to FIG. 15, a schematic illustrates the components to make the toilet (850) automatically flush when the water in the toilet bowl drops close to freezing. A standard manual flush switch (852) can send a pulse signal to the toilet controls (1105), resulting in commencement of the flush cycle when a user manually actuates the switch (852) or when the switch (852) is tripped by a motion sensor, depending on the embodiment. A temperature sensor (1100) can be affixed to the bottom of the bowl of each toilet (850). Leads from the temperature sensors (1100) can be connected to a temperature controller (1110). When one of the sensors (1100) reports temperatures near freezing, the controller (1110) can activate a relay switch (1120), which can send a pulse signal to the associated toilet controls (1105), resulting in commencement of the flush cycle. The signal between the controller (1110) and the relay switch (1120) can be moderated by a delay timer (1130). The delay timer (1130) can prevent subsequent automatic flushing pulses from being transmitted to the toilet controls (1105) until enough time has passed to allow the metal toilet bowl to warm to a temperature at or near the temperature of the water in the bowl. Referring to FIGS. 11-15, as an alternative to or in addition to automatic flushing, the temperature sensors (1100) and the temperature controller (1110) can be wired to open a circuit to shut off power to an electric strike (such as the strike (324) discussed above and illustrated in FIG. 5) for the associated toilet room door (840), thereby automatically locking the toilet room door (840). This can be done when one of the sensors (1100) reports freezing temperatures (i.e., temperatures that indicate water in the system could be frozen, such as temperatures at a predetermined level near, at, or below freezing). Some other temperature sensor, such as a thermostat within the restroom building (802) could be used instead of the temperature sensors (1100) affixed to the toilet bowls. This automatic door lock feature can keep users from continuing to use the restroom system (800) while water in the restroom system is frozen. As is discussed herein, the equipment in the restroom system (800) can be designed to survive freezing water, such as by including elastomeric water lines (892) that can withstand freezing water, and having a submersible water pump that is submerged in the water tank (872) to help avoid freezing of the water pump.
Retrofitting an existing precast vault restroom building to convert it into the restroom system (800) with ultra-low volume flush toilets will now be described. The precast house can be lifted or jacked off the existing precast vaults below so that impermeable liners or coatings (873) can be installed in the unused chambers under the front of the building for service as water storage tanks (872). The unused chambers in the existing precast vaults may be used as water storage vaults (872) without applying sealants or installing liners if these chambers are found to be water-tight. If this is the case, lifting or jacking up the existing building (802) can be avoided by sealing the drains located in the floor of the unused vault chambers with a non-shrink grout placed through a hole drilled in the floors (804) of the toilet rooms (820). These drilled holes can be filled in or fitted with a cover plate after the grouting operation. As an alternative to using the existing unused chambers, a new water storage tank can be placed outside of the existing building's footprint. The existing sewage-holding vaults (860) typically will not require modification, except that they can be equipped with float switches (868 and 869), which can be hung from the bottom of the cover plate (848). The electrical wiring for the float switches can be routed through a hole in the cover plate (848), through the base of the toilets (850) into the mechanical room (828). Holes can be core drilled through the floor (804) of the building (802) above the sewage-holding vaults (860) to add the quick-connect pump-out pipe (864), a through-the-roof vent (865), and urinal drains (867). The restroom building (802) can be equipped with the electrical and plumbing equipment discussed above, including the toilets (850), water pump (884), accumulator tank (886), solar panel (912), controller (914), and storage batteries (916). The existing flue stacks can be replaced with stacks (918) of the same dimensions, except that the flue stacks (918) can have airtight seals at their bottoms and be equipped with a side vent corresponding to the flue-to-toilet room grill (934). One flue stack (918) can have the solar panel (912) attached to a rotatable mounting (920) at the top. Holes can be drilled through the roof (812) and ceiling of the mechanical room (832) for running the electrical cables serving the solar panel (912).
Holes can be core-drilled through the floor above the water storage vault for the addition of water fill pipes (880), and water lines (892). The outside walls of each water storage tank (872) can be cored or cut to allow penetration of the downspouts (878) of the rainwater collection system (874). These openings can also serve as overflow drains for the water storage tank (872). Access holes (854) for the toilets (850) can be cut out of the side interior walls (822) behind the toilets (850) to allow access for water supply lines (892).
A ceiling (832) can be installed above the mechanical room (828). Ceiling insulation (844) can be applied to the mechanical room ceiling (832). Mechanical room wall insulation (846) can be applied to the side interior walls (822) in the mechanical room (828). Further, insulated wall panels and insulated ceilings (not shown) can be added to the toilet rooms (820). The building's (802) restroom doors (840 and 842) can be insulated and fitted with weather-stripping and thresholds to reduce undesirable airflow. The water lines (892) in the mechanical room (828) can be elastomeric to inhibit breaking if water in the water lines (892) freezes. The existing sewage waste tank access holes and covers (863) can remain unchanged. The existing floor openings for the vault toilet riser are shown being closed off with a sealed cover (848), which can be a plate or the floor openings could be filled with doweled concrete plugs or covered in some other manner. Lighting could be added (not shown).

IV. Techniques for Making and Using Restrooms

Referring to FIG. 16, general techniques relating to fixed-in-place stand-alone flush restroom systems will be described. A restroom system, such as one of the restroom systems (100, 410, 610, 800) described above or some other restroom system, can be provided (1200). Sewage can be received (1210) one or more times in the restroom system, and a toilet can be flushed (1220) one or more times. The sewage effluent can be transported (1230) to a sewage-holding vessel, such as a tank or vault. The effluent can be extracted (1240) from the vessel to a sewage hauling vehicle, such as by pumping, and can be transported (1250) in the sewage hauling vehicle.
Referring to FIG. 17, providing a flush restroom system can include retrofitting an existing vault or composting toilet system. This can include replacing (1300) a vault or composting toilet with a flush toilet, connecting (1310) the toilet to a water supply, and connecting (1320) the flush toilet restroom system to a power supply. The flush toilet can also be connected (1330) to a source of pressurized air.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims

1. A method comprising:

receiving sewage in a flush toilet in a restroom system, the restroom system comprising:

a fixed-in-place restroom building;

a flush toilet housed in the restroom building;

a water supply system in communication with the flush toilet; and

a sewage-holding vessel in communication with the flush toilet;

supplying water from the water supply system to the flush toilet in an amount less than 1 gallon of water per flush; and

transporting sewage effluent from the flush toilet to the holding vessel.

2. The method of claim 1, wherein the method further comprises automatically locking one or more doors in the restroom building when freezing temperatures are sensed within the restroom system.

3. The method of claim 1, wherein the method comprises non-residential use of the restroom system.

4. The method of claim 1, further comprising:

extracting the sewage effluent from the sewage-holding vessel and to a sewage hauling vehicle tank; and

transporting the sewage effluent in the sewage hauling vehicle tank.

5. The method of claim 1, wherein the restroom system further comprises a waterless urinal in communication with the sewage-holding vessel.

6. The method of claim 1, wherein the restroom system further comprises an electric power supply system.

7. The method of claim 1, wherein transporting sewage effluent from the flush toilet to the holding vessel comprising introducing pressurized air to the sewage effluent.

8. The method of claim 1, wherein supplying water from the water supply system comprises pressurizing the water.

9. The method of claim 1, further comprising retrofitting an existing vault toilet restroom building with the flush toilet to provide the restroom system.

10. The method of claim 1, wherein the restroom system inhibits freezing of water in the restroom building.

11. The method of claim 1, wherein the restroom system inhibits freezing of water in the restroom building by passing air through a passage wherein the air absorbs heat from the ground before entering the restroom building.

12. The method of claim 1, wherein the restroom system inhibits freezing of water in the restroom building by automatically flushing a toilet.

13. The method of claim 1, wherein the restroom system inhibits freezing of water in a bowl of the toilet by circulating air through a base of the toilet.

14. The method of claim 1, wherein the restroom system inhibits freezing of water in the restroom building by enhancing circulation of air using a flue stack.

15. The method of claim 1, wherein the restroom system inhibits freezing of water in the restroom building by decreasing circulation of external air through the restroom building during times when an external temperature drops below a predetermined low temperature.

16. The method of claim 1, wherein the restroom system inhibits overflow of sewage from the holding vessel.

17. The method of claim 1, wherein the restroom system directs air through a ventilation system in the restroom building.

18. The method of claim 1, wherein the restroom system does not include septic treatment features.

19. A method comprising:

retrofitting an existing vault or composting toilet restroom system with one or more flush toilets to produce a flush toilet restroom system, the retrofitting comprising:

replacing a vault or composting toilet riser housed in a fixed-in-place restroom building with a flush toilet that is designed to use less than one gallon of liquid per flush in the fixed-in-place restroom building, the flush toilet being in communication with a sewage-holding vessel that was previously in communication with the vault or composting toilet riser;

connecting a water supply system to the flush toilet; and

connecting a power supply system to the flush toilet restroom system.

20. The method of claim 19, wherein the method further comprises automatically locking one or more doors in the flush toilet restroom system when freezing temperatures are sensed within the flush toilet restroom system.

21. The method of claim 19, wherein the method further comprises non-residential use of the restroom system.

22. The method of claim 19, wherein the vault or composting toilet restroom system is a vault toilet restroom system, and wherein the vault or composting toilet riser is a vault toilet riser.

23. The method of claim 19, wherein the vault or composting toilet restroom system is a composting toilet restroom system, and wherein the vault or composting toilet riser is a composting toilet riser.

24. The method of claim 19, further comprising installing a waterless urinal in communication with the sewage-holding vessel.

25. The method of claim 19, further comprising:

receiving sewage in the flush toilet;

flushing the flush toilet, the flushing comprising supplying water from the water supply system to the flush toilet in an amount less than 1 gallon of water per flush;

transporting sewage effluent from the flush toilet to the holding vessel;

extracting the sewage effluent out of the sewage-holding vessel and to a sewage hauling vehicle tank; and

transporting the sewage effluent in the sewage hauling vehicle tank.

26. The method of claim 19, further comprising connecting the flush toilet to a source of pressurized air.

27. The method of claim 19, wherein the water supply system pressurizes water supplied to the flush toilet.

28. The method of claim 19, wherein the flush toilet restroom system inhibits freezing of water in the restroom building.

29. The method of claim 19, wherein the flush toilet restroom system inhibits freezing of water in the restroom building by passing air through a passage wherein the air absorbs heat from the ground before entering the restroom building.

30. The method of claim 19, wherein the flush toilet restroom system inhibits freezing of water in the restroom building by automatically flushing a toilet.

31. The method of claim 19, wherein the flush toilet restroom system inhibits freezing of water in the restroom building by decreasing circulation of external air through the restroom building during times when an external temperature drops below a predetermined low temperature.

32. The method of claim 19, wherein the flush toilet restroom system inhibits freezing of water in a bowl of the flush toilet by circulating air through a base of the flush toilet.

33. The method of claim 19, wherein the restroom system inhibits freezing of water in the restroom building by enhancing circulation of air using a flue stack.

34. The method of claim 19, wherein the flush toilet restroom system inhibits overflow of sewage from the holding vessel.

35. The method of claim 19, wherein the flush toilet restroom system comprises a ventilation system.

36. The method of claim 19, wherein the flush toilet restroom system does not include septic treatment features.

37. A restroom system comprising:

a fixed-in-place restroom building;

a flush toilet housed in the restroom building, the flush toilet designed to use less than 1 gallon of water per flush;

a water supply system connected to supply water to the flush toilet; and

a sewage-holding vessel in communication with the flush toilet to receive sewage effluent from the flush toilet, the sewage-holding vessel including an outlet for extracting sewage effluent from the sewage-holding vessel.

38. The restroom system of claim 37, wherein the restroom system is configured to automatically lock one or more doors in the restroom system when freezing temperatures are sensed within the restroom system.

39. The restroom system of claim 37, wherein the restroom system is in a non-residential setting.

40. The restroom system of claim 37, further comprising a waterless urinal in communication with the sewage-holding vessel.

41. The restroom system of claim 37, further comprising a power system configured to supply electric power to the restroom system.

42. The restroom system of claim 37, further comprising an air pressurizing system configured to supply pressurized air to assist in moving sewage effluent to the sewage-holding vessel.

43. The restroom system of claim 37, wherein the restroom building houses a waterless urinal in communication with the sewage-holding vessel.

44. The restroom system of claim 37, wherein the flush toilet is a first flush toilet and the restroom houses the first flush toilet and a second flush toilet designed to use less than 1 gallon of water per flush, the second flush toilet being in communication with the sewage-holding vessel so that the sewage-holding vessel receives sewage effluent from the first flush toilet and the second flush toilet.

45. The restroom system of claim 37, wherein the water supply system comprises a water-holding vessel.

46. The restroom system of claim 37, wherein the water supply system comprises a water pressurizing system.

47. The restroom system of claim 37, wherein the restroom building is a vault toilet restroom building that has been modified for use with the flush toilet.

48. The restroom system of claim 37, comprising means for inhibiting freezing of water in the restroom building.

49. The restroom system of claim 37, wherein the restroom system is configured to inhibit freezing of water in the restroom building by passing air through a passage wherein the air absorbs heat from the ground before entering the restroom building.

50. The restroom system of claim 37, wherein the restroom system is configured to inhibit freezing of water in the restroom building by automatically flushing the flush toilet.

51. The restroom system of claim 37, wherein the restroom system is configure to inhibit freezing of water in the restroom building by decreasing circulation of external air through the restroom building during times when an external temperature drops below a predetermined low temperature.

52. The restroom system of claim 37, wherein the restroom system is configured to inhibit freezing of water in a bowl of the flush toilet by circulating air through a base of the toilet.

53. The restroom system of claim 37, wherein the restroom system is configured to inhibit freezing of water in the restroom building by enhancing circulation of air using a flue stack.

54. The restroom system of claim 37, comprising means for inhibiting overflow of sewage from the holding vessel.

55. The restroom system of claim 37, further comprising a restroom ventilation system.

56. The restroom system of claim 37, wherein the restroom system does not include septic treatment features.