Page 140 - Villas at Savona Close-out Manual

If a drywell is draining slowly or leaves water standing over the grate for longer than regulations allow,
debris may simply be blocking the inlet. The maintenance guidelines begin with the performance of an
annual inspection, which should include assessing the need for cleaning and inspecting the functional and
structural continuity of the system. At the same time, surface aspects of the drainage way are evaluated for
evidence of staining or standing water.

A typical cleaning is carried out using a truck-mounted hydro-vactor (see below) when accumulated trash,
debris, and sediment occupy 15% or more of the original settling chamber capacity. The hydro-vactor
utilizes streams of air and high-pressure water to dislodge built-up material, which is then removed via
vacuum hose and disposed of off-site.

Inlet grates and covers are removed for this operation and all filters and screens are cleaned during this
procedure. At the same time, any obstructions or accumulated debris in remote inlets and connecting pipes
is removed by jet-rodding. The cleaning operation also involves replacement of the floating absorbent
pillows and changing out the filter fabric at the bottom of the chambers where applicable.

After the initial cleaning, most systems generally will not require subsequent cleaning for 3-5 years. When
afforded regularly scheduled maintenance, our records indicate that our MaxWell Drywells will provide
decades of efficient, reliable service.

A written log shall be kept of all inspections and maintenance actions performed on the drywell systems.

Typical Hydrovactor Truck used for Drywell Maintenance

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