Design capacities of the lift station approximately 1670 m3/h. The GWC’s initial goal for this project is to develop a prioritized list of repair/refurbishment projects based upon a comprehensive condition assessment and criticality analysis of IPS lift station planned to remain in operation.

1. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS

2. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS
TABLE OF CONTENT
0 PREFACE.......................................................................................................................
0.1 Purpose of this document ........................................................................................
0.2 Overview ...................................................................................................................
0.3 Abstract......................................................................................................................
0.4 Scope..........................................................................................................................
0.5 Objectives...................................................................................................................
0.6 Time Line...................................................................................................................
EQUIPMENT TECHANICAL DATA ..........................................................................
0.1 Mechanical Screen....................................................................................................
0.2 Penstocks ...................................................................................................................
0.3 Ultrasonic level...........................................................................................................
0.4 Pipes and fittings.........................................................................................................
0.5 Ventilations..................................................................................................................
0.6 Switchboards ...............................................................................................................
0.7 Lighting and cabelling................................................................................................
EQUIPMENT TECHANICAL CATALOGUES ...........................................................
0.1 Mechanical Screen....................................................................................................
0.2 Penstocks ...................................................................................................................
0.3 Ultrasonic level...........................................................................................................
0.4 Pipes and fittings.........................................................................................................
0.5 Ventilations..................................................................................................................
0.6 Switchboards ...............................................................................................................
0.7 Lighting and cabelling................................................................................................

3. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS
0.1 PURPOSE OF THIS DOCUMENT
This document is a generic Technical Proposal Submitted to ICDOC. It provides
guidance to methods and material which is intended to assist in achieving project
goals. It is also useful background reading for developing and monitoring installation
quality.
0.2 OVERVIEW
Design capacities of the lift station
approximately 1670 m3/h. The
GWC’s initial goal for this project
is to develop a prioritized list of
repair/refurbishment projects
based upon a comprehensive
condition assessment and
criticality analysis of IPS lift
station planned to remain in
operation.
The remaining sections constitute a
technical data that should be used to construct the project-technical submissions.
0.3 ABSTRACT
#1 Industrial cities development and operating company (ICDOC) are contracted to
MODON to provide water and wastewater concessionary services to the industrial
cities under a bot contract model
for Dammam 2 industrial city.
#1 The Dammam 2 IPS mechanical
coarse screens, screen refuse
system, dry well pipework, valves,
ventilation fans and control
panels are old and require
immediate
maintenance/replacement in order
to provide security of operation of
the IPS.
#2 The installation of two new
pumps, piping and electrical
works has been completed and is operational. Two further new IPS pumps have been
purchased to replace existing two old pumps.
#3 The following workscope provides details of the work required to achieve the
objective of the IPS being able to accept the current inflows efficiently and provide an
acceptable level of standby facilities.

4. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS
#4 ICDOC is seeking to appoint a
suitably qualified contractor to
undertake the design, supply,
construction and installation,
testing and commissioning of
the required works.
#5 GWC wound up itself in full
competence to do such work
because of their long experience
in this field
#6 This Technical Proposal is
issued in order to receive
proposals to undertake the work as further described in ICDOC RFP document.
#7 This Technical Proposal has been set up to demonstrate our ability to attain this work
executed through the implementation mechanisms and materials clarified under
0.4 SCOPE
#1 Divert the IPS incoming influent from an existing manhole at the plant boundary
directly to the plant head works during execution of the works.
#2 Operation of the equipment and ensure no overflow shall occur during this period.
#3 Dry pumps wet well in order to clean and repair of concrete surfaces and treat the
defected parts.
#4 Remove defected mechanical parts and installing the new ones.
#5 Follow HSE plan
0.5 OBJECTIVES
This project is divided into five (4) objectives:
Objective 1 – Emphasize IPS Lift Station status quo and main Improvement Works
Objective 2 – Wet Well Assessment and Implementation Procedure
Objective 3 – Drawdown Testing Procedure
Objective 4 – Setup bypass pumping system, Install New equipment
Objectives may be performed concurrently.
Objective 1 – Emphasize IPS Lift Station status quo and main Improvement Works
o Collect a detailed information. GWC will request detailed information from the
ICDOC which is required to complete the IPS lift station by pass activities, and will
coordinate with the operation and maintenance department to obtain this information.
The data request is expected to include, at a minimum:
· Lift station operation and maintenance manuals

5. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS
· Plan metric data and sanitary sewer data
· Operation and maintenance data including daily pump run (hours) data
· Maintenance records
· Sanitary sewer overflow (SSO) records of IPS lift station-related spills
o GWC will arrange with appropriate ICDOC staff to become familiar with the IPS
wastewater lift station system and to obtain input on the proposed work plan.
o Engineer will interview IPS operating staff regarding operability and observed
deficiencies at each of the lift stations to be assessed. Engineer will note ICDOC staff
comments about observed deficiencies or problems anticipated to be encountered
during assessment activities. Engineer will communicate results of interviews to IPS
station’s project manager and to field assessment teams.
Objective 2 –Wet Well Assessment and Implementation Procedure
o GWC will perform a multi-gas detection test on the unopened wet well by inserting
the gas detector hose into the wet well hatch hole to measure air quality. The
presence of hydrogen sulfide will be checked as a potential indicator of a corrosive
environment.
o After recording gas concentration, Engineer will request ICDOC staff to turn on the
wet well HVAC (Ventilation System) and open hatches. GWC staff will perform a
permit confined-space entry into wet wells.
o Once the hatch is open, fall prevention devices provided by the Engineer will be
placed over the hatch opening and a quick review of the wet well will be performed to
determine the optimal locations for power washing and scratch testing.
o The water level in the wet well will be lowered by starting the pumps. The pump’s
vent line operation will also be monitored during lowering of the water level.
o A vertical area along one side of the wet well wall will be washed using a power
washer (provided by the GWC) and a scratch test will be performed on concrete wet
well walls.
o Tests will be performed with the aid of a pole-mounted device; staff will perform a
permit confined-space entry into wet wells to conduct scratch tests.
o Condition of the wet well walls, slabs, piping, valves, floats, ladders and rails will be
visually inspected. Digital photographs or video will be collected.
o Measurements will be taken of the wet well across the day hours to determine
operating levels: Low, Lead On, Lag On, High, and other alarm levels. Engineer will
use a portable leveling rod to make measurements. This information will be required
for determining available wet well capacity and for lift station drawdown tests.
o Based on visual assessments, Engineer will provide a detailed report for wet well
structures applied methods to treat surfaces and appropriate materials. For
structures with significant visible degradation.

6. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS
Expected support from ICDOC:
o Providing access to lift stations for Engineer staff
o Opening electrical panels, guards, or hatches for Engineer to visually evaluate
electrical components
o Operating lift station electrical system (i.e. turning the power off/on to the pumps).
This will include drawing down the level of the pumps to allow Engineer to take
measurements of the operating levels.
o Performing pressure washing of an area along one site of wet-well walls to ensure
degreased prior to assessment.
Objective 3 –Drawdown Testing Procedure
o Engineer will perform pump drawdown tests over an approximate seven-day period
for
IPS lift station. The drawdown testing will be used to determine the flow
characteristics of lift station, as well as to diagnose potential problems.
o Engineer will provide and install a suitable number of Diesel Pumps with appropriate
capacity in order to perform a seven-day pump drawdown test.
o The Flow Monitoring process will log and record start and stop times of pumps at the
lift station as the wet well fills and is emptied. Pump activity data will be stored and
data will be analyzed.
Flow Monitoring process with known volumes between level switches in the wet well,
an algorithm provided is used to calculate flow into and out of the IPS lift station.
The Flow Monitoring will be used to determine:
-Total and average inflow
-Minimum and maximum inflow and times of occurrence
-Inflow and outflow for each fill and empty cycle
-Data on combinations on pumps
o Seven or more cycles of filling and pumping are necessary to analyze the filling and
pumping of the lift station. To ensure adequate data is collected for analysis, seven
days will normally be allotted for monitoring. In addition to determining pump
performance, the process may also assist with identifying lift station performance
issues, including alternator failures.
o Upon the completion of flow monitoring, Engineer will collect and analyze data.
o Engineer will evaluate wet well storage capacity and number of pump starts observed
during flow monitoring, and compare with normal pump station operation.
ICDOC responsibilities include:
o Operating lift station electrical system (i.e. turn power off/on to lift station pumps)

7. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS
Objective 4 – Setup bypass pumping system, Install New equipment
Isolating pumping stations from incoming flow
o Sewage generally arrives at a pumping station via a gravity main. Irrespective of the
type of pumping station, there are times when a pumping station must be wholly or
partially closed down for maintenance or further works. This means that sewage must
be prevented from entering the wet well. The wet well is provided in the pumping
station, storage of sewage under shut down conditions must be considered, Hence,
shut down for an extended period is being proposed, bypassing with temporary diesel
pumping are necessary.
o Before the station is taken offline and work begins, a temporary bypass pumping
system must be set up and functioning to ensure wastewater continues to flow to the
treatment plant. The bypass will consist of installing a discharge pipeline with a
suitable diameter with necessary connection between the nearest sewer manhole on
the gravity mail line (900 mm) and the treatment plant existing inlet structure. Diesel
pumps will then be brought in to pump from our wet well to the bypass connection
outside the station. This will isolate the building and allow the proposed work to
commence.
o The arrangement used to cut off sewage flow to pumping stations with diesel pumps is
to take in consideration the required period and inflow regarding drawdown test. The
required pump by ICDOC are 2*625 m3/hr diesel pump which will bypass the whole
sewer with a proximately 300 M of hose line. In addition, this pump is working during
possible periods of extensive power outages, mandatory power reductions, or
uncontrolled sewer events, consideration should be given, which shall be made to
drain to the station wet well.
o After install the diesel pump and switch it on for a proper while to obviously notice
and ensure its adequate for the job to drain the main wet well where mechanical
screens are located. The 2*625 m3/hr diesel pump will be installed near the inlet-
structure above the 900 mm manhole. For the inlet manhole to the IPS station another
diesel pump will be installed to connect that manhole with one of the two minor wet
well where pumps wall connection are located. First it will be the minor wet well
which has the newest pumps. That time will be decided according to the calculations
and measures from the drawdown test and arrangement with ICDOC. While all diesel
pumps are working to drain the pump with the IPS pumps, the 1000 mm balloon will
be immediately installed to isolate the pump station.
o Replacement works on the two wet well will be in sequence. Proper valve selection
and placement is critical to the station's ease of maintenance and operation, overall
station flexibility, and reliability. The following criteria have been developed for
valves at the lift station. Valve location will be selected for accessibility. Submersible

8. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS
pumps will have discharge valves located in a valve vault. All installed valves will be
constructed of material resistant to corrosion and suitable for wastewater service.
Check Valves and Pump Discharge Isolation Valves
o Each pump discharge will include a swing check valve to prevent backflow in the
system from damaging the pump. Each pump will be provided with its own discharge
valve to isolate the pump from the system. There is currently no isolation valve on the
system between the pump station and the discharge line. A manually operated gate
valve is recommended downstream of the flow meter in order to isolate the station
and accommodate maintenance.
Wet-well Isolation Gate(s)
o A type 316 stainless steel slide gates will be provided on the wet-well influent to
isolate the pump station from the gravity system. The gate will be manual or actually
operated as required.
Mechanical Screens
o To be installed after wet well treatment and meanwhile pumping station is out of
service
Electrical panels and control work
o To be installed meanwhile pumping station is out of service.

9. ProjectTimeLine

10. DAMMAM SECOND INDUSTRIAL CITY - IPS REHABILITATION WORKS