© IWA 1
st
International Symposium on Water and Wastewater Technologies in Ancient Civilizations,
Iraklio, Greece, 28-30 October 2006
Evolution of Land Treatment Practice for the
Management of Wastes
V. E. Tzanakakis, N.V., Paranychianakis, and A.N. Angelakis
National Agric. Res. Foundation, Inst. of Iraklio, 71307 Iraklio, Greece, nvpar@her.forthnet.gr
Abstract: “Land treatment” refers to the application of wastewater to the soil to achieve
treatment and to meet irrigation needs of the vegetation. Application of wastewater to the land
was the first practice used to protect public health and control environmental pollution and
has gone through different stages of development with time. Currently, its application has
been expanded for the treatment of various types of wastewaters including dairy, meat,
industrial effluents as well as and polluted water sources. It is recognized as the ideal
technology for rural communities, clusters of homes and small industrial units due to low
energy demands and low operation and maintenance costs. A brief historical overview along
with an introduction to the fundamental processes the current trends and the future prospects
are provided in this section.
Keywords: History of land treatment; sewage farms; wastewater management; sanitation.
Introduction
Land treatment is defined as “the controlled application of partially treated wastewater onto
land to achieve treatment and disposal goals in a cost-effective manner” (Crites et al., 2000).
Land application is the oldest practice used to manage wastewater and control environmental
pollution. Land treatment systems have a long history as evidenced by the elaborate
sewerage systems associated with ancient palaces and cities of the Minoan Civilizations.
Indications for disposal of wastewater in agricultural land extend back approximately
4500years ( Asano and Levine, 1996; Angelakis and Spyridakis, 1996; Angelakis et al.,
2005). With the progress of the time the land treatment has gone through different stages of
development but the basic principles regarding planning, operation and management
practices were developed after 1850 when the “sewage farms” were expanded in Europe and
USA in an effort to control pollution and protect public health (US. EPA, 1979).
The development of conventional wastewater treatment technologies in the turn of 19
th
century resulted in a decline of land treatment systems (Reed et al., 1995), but the interest
was renewed after the passage of Clean Water Act in 1972 (PL 92 500) and particularly the
last two decades (Paranychianakis et al., 2006). This is mainly due to the low construction,
operation and maintenance costs, making this technology suitable for small communities or
decentralized clusters of homes, institutions and isolated industrial units (Crites and
Tchobanoglous, 1998; Angelakis, 2001). Different types of land treatment systems were
developed through the passage of time depending on the rate of applied hydraulic load, the
presence or absence of vegetation, the needs for preapplication treatment and the intended
level of treatment. These include: a) Slow Rate systems which utilize soil matrix for
treatment and the applied load is based on vegetation water requirements; Overland Flow
which utilize soil surface and vegetation for treatment and the treated wastewater is collected