Flow Survey ManagementPlanning & Data Auditing

Ravikeerti S. Patil

25 June 2010

Understand project objectives:• model type and objectives will determine no, location, spread and

density of monitoring equipment

Programme and duration?• contractor and equipment availability

Desk study in first instance:• what information is available to complete flow survey planning

stage

Field surveys:• check each proposed site and at least two alternatives with the

contractor

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Flow Survey Planning

Factors affecting flow monitoring locations:• H&S – no compromise,

• access to the site,

• size of a pipe and flow depth,

• monitor location – incoming / outgoing pipe,

• flow conditions,

• gradient,

• Velocity,

• manhole condition,

• bends, junctions, backdrops etc.

Improving flow monitoring sites

Site Selection is crucial to returning good quality data.

Flow Survey Planning

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FM Performance Polygon & Monitoring Locations

FM Location

RG Location

Installation reports:

• flow monitor is in right manhole

• flow conditions – visual or on-site

• pipe shapes and sizes

• silt measurements

Weekly reports

Calibrations reports

Velocity, depth and pressure sensors are working

Flow Data Analysis: Important Checks

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Flow Monitoring Schematic

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Level and velocity profile are good, Scatter is tight – Very Good Data

Level and velocity profile are good, Scatter is bit wider – Good data

Previous Week | This week Previous Week | This week

Data Quality Grading

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Level data good but velocity profile bit noisy - Scatter is wider – Reasonable Data

Level and velocity profile are very noisy (pumping profile), Scatter is not so good – Bad Data

Previous Week | This week Previous Week | This week

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Data Quality Grading

Regular Maintenance Activity – Flow diversion at u/s of monitoring point

Regular Maintenance Activity – Weekly Siphon Flushing on Monday

Flow Data Analysis

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Temporary ragging caused level and velocity data degradation

Surcharge in the system caused velocity sensor to malfunction

Flow Data Analysis

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Flow

m3

/sPeak Propagation and Volume Balance

Data Quality Grading Summary

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Data quality

Any missing or bad data

Identifying storm event

• Total depth

• Minimum Intensity

• Storm Duration

• Percentage variability

Identifying dry day period

Serviceability of flow monitors

Rain Data Analysis and Event Selection

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Rain Data Analysis and Event Selection

Data sources:• Weekly flow and rainfall data,

• SCADA data, if any,

• Flow data - permanent / temporary flow monitors, if any,

• Online checking of rainfall data,

• Application of radar data to analyse spatial variation,

• Regular site visits

Flow Survey Management: In General

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Flow data analysis and data checks:

• Weekly data quality checks of flow and rainfall data,

• Liaising with the client on regular basis regarding:- data quality, relocation issues, calibration checks,- operational issues, health & safety issues, traffic management

plans etc.

• Producing and issuing progress reports,

• Regular meetings with the Contractor

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Flow Survey Management: In General

Thank You