SIDEF Consultants Pvt. Ltd.

Project information

Category: Water Supply & Sanitaion
Client: Kathmandu Valley Water Supply Management Board
Project Start Date: November, 2022
Project End Date: October, 2024
Scope of Services: Bagmati Province, Nepal

Project Description

The main task of the consulting service is to conduct the Detail Engineering Design of all the components of the Sisneri Water Supply System including Detail Drawing, Cost Estimate and preparation of Procurement Documents Works. The consultant also shall prepare the scoping document and Terms of Reference (ToR) for the Environmental Impact Assessment (EIA) of Sisneri Water Supply Project and (ii) Preparation of Detailed TOR for Design of the Sisneri Dam. The Consultant shall follow National/International best practice during survey, design, and report preparation in close coordination with KVWSMB. Total project Cost: NPR 33,077,714,105

Services

Type of Scheme

Dam storage with multi stage pumping system

Intake

Submersible Pumps: 21 sets installed at the dam with a capacity of 110 LPS each.

Water Conveyance and Pumping System

Total Pipe Length: 27.03 km
Pipe Material: Ductile Iron
Valve and Accessories: SCADA friendly; rated pressure ≥2 times working pressure
Discharge: 140 MLD (1.62 m³/s)

Pumping Line 1 (Dam Intake to Reservoir Tank)

Length: 306m
Pipe Diameter and Nos: 3 Nos of 800mm
Static Head: 163m
Total Pumping Head: 302m
Pump: 21 sets (15 operation + 6 standby), each 110 LPS

Gravity Line (Reservoir Tank to Water Treatment Plant)

Length: 8690m
Pipe Diameter and Nos: 3 Nos of 800mm
Static Head: 70m
Total Residual Head: 59.03m

Pumping Line 2 (Water Treatment Plant to Sainbu RT)

Length: 8,066m
Pipe Diameter and Nos: 2 Nos of 1000mm
Static Head: 155m
Total Pumping Head: 316m
Pump: 21 sets (15 operation + 6 standby), each 110 LPS

Reservoir Tank

Capacity: 6000 m³
Retention Time: 1 hour
Placement: Underground
Structure Type: RCC

Water Treatment Plant

Type

Conventional (Flocculation, Sedimentation, Rapid Sand Filter, Chlorination)

Capacity

140 MLD (1.62 m³/s)

Components

Receiving Chamber: RCC rectangular tank, detention time of 4.19 minutes.

Distribution Chamber: Weir Type, 298.72 m³, detention time 3.07 minutes.

Coagulant Mixing: 7 Nos, weir type using potential energy.

Flocculation: Vertical-baffling type, 7 Nos, detention time 30 minutes.

Sedimentation: Horizontal flow type, 7 Nos, detention time 128 minutes.

Sludge Discharge: Hopper type, 84 Nos, capacity 16.9 m³ each.

Rapid Sand Filtration: 28 chambers, constant flow with surface washing.

Clear Water Storage: 2 Nos, each 3150 m³, detention time 65 minutes.

Chemical Dosing: Six chemical mixing tanks and three dosing tanks.

Sterilizing Agent: Bleaching powder.

Filter Washing: Backwashing by filtered water, backwash rate 0.6 m³/m²/min.

Access Road

Length: 10.054 km
Terrain: Hilly
Altitudinal Range: 1310m – 1295m
Proposed Pavement: Premix
Standard: Nepal Road Standard 2070 BS
Formation Width: 5-6m
Maximum Gradient: 16%

Bridge

Name of River: Bagmati River
Total Length: 80m
Span Arrangement: 1x 80m
Superstructure: Steel Superstructure
Abutments: Rectangular Steel with cantilever return walls
Foundations: Open foundation
Design Load: Class A (Single Lane)

Power Supply

Power Demand: 10 MW
Transmission Length: 56.02 km
Transmission Voltage: 33 kV (2 Circuits)
Substations: Dukuchhap Pumping Station, Sisneri Damsite Pumping Station