2 Dust Ash Manufacturing is hoping to increase its revenues
Solution
Glancing back through history, waste disposal became increasingly urgent as population
 density increased. Solutions for how to best handle biological waste have been evolving
 ever since. In many areas serious waste treatment strategies did not emerge until the
 19th century when correlations were drawn between waterborne illnesses and human
 contact with waste. Over time, centralized systems displaced decentralized systems
 because they were thought to better protect citizens from rampant disease, as well as
 easier to maintain and operate in compliance with impending laws.
 In the United States, technologies for carrying away waste date back to the mid to late
 1700s, about 100 years after communities began installing fresh water conveyance
 systems. In the Puget Sound, many early communities collected their waste in wood
 chutes, boxes and troughs and discharged it to the most convenient point, usually local
 water bodies at a lower elevation. The fi rst large-scale strategy to replace the privy
 vault and cesspool systems was the centralized water-carriage sewer system. This
 system solved some problems and created others, especially in more densely populated
 communities. Many city residents accepted the
 sanitation problems and nuisance
 conditions such as odor as a necessary
 part of urban life.1
 But because it wasn’t
 widely understood that biological waste
 could contaminate water sources, open
 sewers lined the streets. First-fl oor
 dwellers could often connect to the
 sewer system via a drainpipe but it was
 commonplace for upper-story households
 to cast their biological waste products
 out the window to the streets below.
 City boosters advocated for centralized
 waste management and sewer systems,
 believing it would help attract people
 and industries with a cleaner urban
 image. Opponents to centralized waste
 management and sewers argued that
 a source of fertilizer would be lost, soil
 and water supplies would be polluted at
 the system outfalls and “modern sewer
 systems” would create and concentrate
 “disease-bearing sewer gas”.2
 The design of the early centralized
 systems was also vigorously debated,
 pitting advocates for combined sewer
 systems against proponents for separated sewer systems. The combined sewer systems
 used a single pipe to transport both stormwater and wastewater to a designated disposal
 location, as opposed to the separated sewer systems which required laying two pipes.
 Many cities unwittingly installed combined systems because they were thought to be less
 expensive to build, unaware of the environmental problems that would later be imposed
 on discharge sites.
 In Olympia, “adequate fl ushing and some dilution were seen as benefi ts over separate
 sanitary sewers.”3
 It was a widely held belief that ‘dilution was the solution to pollution’,
 making combined systems the superior choice. But as populations in cities grew and it became necessary to treat sewage to alleviate
 nuisance pollution problems, cities with
 combined systems now had signifi cantly more
 volume to clean.
 Major advancements in sewer system design
 did not take place until the end of the 19th
 century when studies emerged demonstrating
 that sand fi ltration processes could help lower
 the infection rate of waterborne illnesses such
 as cholera, dysentery and typhoid. It was at this
 time that sewage treatment plants became
 commonplace.
 Even after the King County Board of Health
 passed a resolution that required all
 wastewater discharged to Lake Washington to meet the United States Public Health
 Service bacteriological standard for drinking water, community members demanded
 that intercepting pipes divert the effl uent away from Lake Washington. Outfalls were
 connected to the intercepting pipes by 1936, but large storm events continued to cause
 overfl ows that polluted Lake Washington. Many cities with similar situations began
 building ‘compound systems’ — combined sewer systems in some areas of town
 and separated sewer systems
Decentralized and distributed wastewater treatment strategies should not necessarily be
 managed at the municipal level by publicly-owned utilities alone. As such, the cost burden
 for treatment systems, as well as their ongoing operation, maintenance and replacement
 needs can be shifted from the utility to the individual project owner. While this can create
 fi nancial barriers for project owners, unique opportunities exist for utilities to develop fee
 structures and incentives to support the transfer of capital cost, expense and revenues
 to offset an owner’s upfront investment in on-site water systems.14 Utilities could even
 develop a new revenue stream by providing system maintenance and testing to ensure
 operations perform at required public health levels.
 A project owner’s upfront investments in on-site treatment systems can create
 burdensome fi nancial barriers. Even when life-cycle costs are taken into account,
 artifi cially low utility rates for water and wastewater services translate to long payback
 periods. Not all utilities use full cost pricing — past and future, operations, maintenance
 and capital costs — to establish rates for water and wastewater services and therefore
 miss an opportunity to encourage conservation and reuse strategies employed by
 alternative waste treatment systems.
 Financial barriers for distributed water systems can be directly related to the regulatory
 barriers noted above. Backup or redundant connections to municipal wastewater utilities
 may be required by codes even when a system is designed and operated not to use
 them. Composting toilets sometimes require backup sewer connections and associated
 plumbing, creating a fi nancial disincentive for project owners to even consider their
 use. Likewise, capacity charges are established by utilities to recoup sunk costs for
 large investments in centralized infrastructure projects and are required to be paid by
 all building projects located within their service area, regardless of whether or not onsite systems can be utilized to meet individual treatment needs. Some municipalities
 have instituted innovative fee structures, such as the City of Portland’s Bureau of
 Environmental Services in Oregon, which allows for emergency-only connections to their
 wastewater treatment facilities but charges large use fees in the event that the utility
 connection is actually needed.
 Removing regulatory barriers to decentralized systems can help spur market innovations
 and new products available to designers and homeowners pursuing decentralized and
 distributed systems, thus bringing down upfront costs and reducing life-cycle cost
 payback periods. For years, fi nancial incentives for energy effi ciency measures and onsite renewable energy generation have been accelerating market adoption, serving as
 examples for similar approaches for decentralized and on-site wastewater systems.


