Mis. Osborne
November 18, 2016
Page 30f5
6.
identify equipment, structure, piping, controls or operations related issues affeciing tne Wet
Weather Facility’s capacity to effectively handle and treat the identified design peak flows
reaching the facility;
Develop a capital upgrade plan to address identified issues.
SCOPE OF SERVICES
Based on the present conditions and project objectives listed above, we have developed the following
proposed scope of services:
A. Influent Hydraulic Analysis:
1.
8.
Meet with City staff to confirm the hydraulic basis and objectives, including plant influent flows
ana anv other observed hydraulic limitations (e.g. hydraulic bottlenecks, or unequal flow split
issues).
Review wet weather flow influent pumping systems operational information for the present
operational approach, and key wet weather flow equipment systems.
Review the existing record drawings to verify dimensional and layout information of structures
and flow path elements, such as piping, valves, instrumentation, weir locations and heights.
Review existing information on the projected peak flows from the three influent sewers to the
plant, and evaluate the effective hydraulic capacities of the existing influent sewer system in the
immediate vicinity of the Wastewater Treatment Facility (considering pipe size and slope).
Investigate the rated capacity of the drop shaft vortex manhole, as well as possible operational
issues and subsequent modification options.
Evaluate the operation, control and calibration of the wet weather flow pumping facility,
including gates and equipment (influent screens and pumping system).
Develop a hydraulic model of the plant influent systems, including the influent sewers (on the
treatment facility property), and the influent hydraulics of the main pump station and wet
weather pump station. The model will be developed using the record drawings information.
a. Obtain historic data and cbservations on the water surface elevations, and flow data at
the wastewater treatment facility. Calibrate the model using available historic water
surface elevation and flow information.
b. Based on the projected flows, evaluate the design conditions for the wet weather systems
to flag what is undersized and robbing the needed system’s capacity.
c. Use the model to evaluate specific modification options to the structures and piping, or
control strategies to minimize future untreated wastewater overflows.
identify equipment, structure or piping capacity issues that are reducing the treatment facility’s
capability to satisfactorily handle the peak flows reaching the facility.
