A siwes presentation on Water treatment at eleyele Dam

1. PRESENTATION OF STUDENT
INDUSTRIAL WORK EXPERIENCE
SCHEME PROGRAMME (SIWES)
BY
KEHINDE FUNMILAYO LOIS
19/57MB/01217
ELEYELE WATER DAM, OYO STATE

2. AIM OF SIWES (STUDENT
INDUSTRIAL TRAINING FUND)
 To make change from school to work easier.
 To enhance students contact for later job easier.
 To expose students to work methods and techniques in handling equipment and
machinery that may not be available in their institutions.

3. BRIEF HISTORY AND LOCATION
ELEYELE WATER DAM
 Eleyele Dam is an earth dam constructed on Ona River at Eleiyele in the 1940s, for
supplying raw water for treatment at the Eleyele Waterworks for the city of Ibadan, and
also for flood control during high flow period in order to safeguard life and property
downstream of the dam.
 The dam has a total length of 244m which comprises (embankment 138m and spillway
106m) and a crest height of 13.0m. The dam crest has an average width of 4.5m,
overlaid centrally with 1.5m wide concrete walkway which adjoins a concrete block-
work barrier on the upstream side.
 The capacity of Eleyele Lake is 7MCM, with a surface area of 160ha, and a fetch of
2.4km. The maximum reservoir yield is about 2700 cu.m/day. The catchment area of
the dam is 320 sq. km.
 The lake is believed to be heavily silted as a result of urbanization and encroachment of
the flood plain at the upstream side of the reservoir

4. STRUCTURAL ORGANIZATION OF ELEYELE
WATER DAM
CHAIRMAN OF BOARD OF DIRECTORS
GENERAL MANAGER
SECRETARY OPERATION AND
MAINTENANCE
QUALITY
CONTROL
MECHANICAL
AND ELECTRICAL
COMMERCIAL SERVICES
AND FINANCE
DISTRICT
MANAGER
SCHEME
MANAGER
CIVIL
ENG.DEPT
ELECTRICAL
ENG. DEPT
QUALITY
CONTROL
ADMINISTRA
TION OFFICE
MECHANICAL
ENG. DEPT
LABORATORY
SECTION
TREATMENT
PLANT

5. ACTIVITIES CARRIED OUT
 WATER PURIFICATION PROCESS
 PHYSIOCHEMICAL ANALYSIS ON WATER
 BACTERIOLOGICAL ANALYSIS ON WATER

6. WATER PURIFICATION PROCESS
 Stages involved in Eleyele water purifiation process
 Aeration
 The water from the dam through a machine called Low lift pump enters the aerator where
aeration takes place. Aeration is the process of exposing the raw water to the atmosphere
so as to facilitate the removal of odour and the exposure of harmful micro-organisms to
the sunlight rays (UV rays).
Plate 1. Aerator

7. WATER PURIFICATION PROCESS
 Coagulation and Flocculation
 Coagulation
 Coagulation is a process used to neutralize charges by addition of coagulants
with charges opposite to those of the suspended solids in water to form a
gelatinous mass to trap (or bridge) particles thus forming a mass large enough
to settle or be trapped in the filter.
 Flocculation
 Flocculation is gentle stirring or agitation to encourage the particles thus
formed to agglomerate into masses large enough to settle or be filtered from
solution.

8. WATER PURIFICATION PROCESS
 Sedimentation
 This is the second stage at the treatment plant where aggregate or coagulated particles
(flocs) settle due to gravity. This is the process of letting the flocs (suspended material)
in the flocculated water settle by gravity.
 Plate 2. Sedimentation Tank


9. WATER PURIFICATION PROCESS
 Filtration
 After leaving the sedimentation tank (clarifier) via the clarified (settle) water launder or
decanting trough, the water flows by gravity to the filter beds. Here, the remaining very
fine particles are filtered by a sand medium which is generally referred to as a Slow Sand
Filter.
 Plate 3. Filter Bed

10. WATER PURIFICATION PROCESS
 Liming
 Liming is the addition of hydrated lime Ca(OH)2 to neutralize the effect of alum in water thus raising
the pH. It is done after the water leaves the filter bed and before it gets to the clear well tank.
 Disinfection / Post Chlorination
 Disinfection takes place in the clear well where the final water is stored. The importance of this is to:
 Destroy any bacteria (germs) that may be present in the treated water, thereby preventing their growth.
The disinfectant used is chlorine. However, fluorine can also be used but it should be properly
controlled because it is highly hazardous.

11. RECOMMENDATIONS AND
CONCLUSION
 I suggest that the government of Oyo state should consider Oyo State Water Board for
rehabilitation. Because, I think by doing so most of the problems the board is facing
would be tackled.
 I also suggest to Industrial Training Fund (ITF) that they should review the policy of
paying allowance to students on Industrial Training. The policy should be in such a way
that the student will be given small amount every month when he or she is still on the
training program.