Specifications

Section 5 Formulation of Alternative Plans
EAA Storage Reservoirs Revised Draft PIR and EIS February 2006
5-18
excavation of the seepage collection canal. The seepage canal construction would
produce between 5% and 10% of the embankment material. The borrow pits
would produce the required balance of embankment material. Embankments
will be constructed with a crest width of 12 feet. Earthen embankments would
have 1 (vertical) on 3 (horizontal) slopes on both sides. The exterior RCC
embankments would be built with a vertical face on the flood, or interior, side
and a stepped face on the exterior or dry side of the reservoirs. The stepped face
would consist of three equally spaced steps. A 20-foot wide maintenance/service
road would be placed on the toe of the exterior side of either type of
embankment. The road would be unpaved and constructed with the same
limestone material used for the embankment. The interior slopes of the earthen
embankments would be protected with riprap, while the outside slopes would be
grassed. Neither face of the RCC embankment requires any protection or cover.
The embankment located between cells 1 and 2 would not have a service road at
the toe. However, both sides of this “internal” embankment would be protected
by riprap. See Figure 5-5 for a typical earthen levee section and Figure 5-6 for a
typical RCC levee section.
FIGURE 5-5: TYPICAL EARTHEN LEVEE SECTION