UDF Field App

§1Planning and preparation

Segment details from GIS, then the pre-flush checks. Demo values are filled in; tap Start a new flush to clear them.

Date Operator / crew Pressure zone Street / segment Flush hydrant # Monitor hydrant #

Diffuser

Backflow preventer

Distance to catch basin (m)

Pre-flush (§1)

§2Pre-flush calculations

List each pipe section in flow order, S1 nearest the source. The largest main is slowest and sets the flow needed.

Target velocity

Water exchanges

Volume = 0.785 × D² × L × 1,000 per section. Flow needed = Table 1 for the largest main. Time per exchange = total volume ÷ flow. Gauge needed: Hose Monster = first Table 2 row at or above the flow; Pollard = [Q ÷ (29.83 × C × D²)]².

§3Site setup

Static pressure and initial sample (start of flush)

Pressure unit

Start time Static pressure

Sample time Turbidity (NTU) Total Cl₂ (mg/L) Colour

Monitoring for nitrification — SL1000 initial panel

pH NH₂Cl mono (mg/L) Free NH₃ (mg/L) Nitrite (mg/L) Temp (°C)

Valves closed in sequence (§3.8)

Close slowly and fully. Count turns. Re-open in reverse order at §8 and confirm the turns match.

§4–6Live flush

0:00

Diffuser gauge (psi)

Outlet dia. (in) Coefficient C

Monitor hydrant pressure (§5)

Residual now Lowest residual

Mid-peak turbidity (§6)

Time Turbidity (NTU)

Check turbidity every 5–10 min and watch colour; record one mid-peak reading. Throttle back if residual nears 140 kPa (20 psi), drainage is overwhelmed, or a hazard develops.

§7Ending the flush

Sample time Turbidity (NTU) Total Cl₂ (mg/L) Final static Actual flush time (min)

Flush complete when all pass

§8Shutdown and restoration

Valves re-opened (reverse order)

End time Operator sign-off

Issues

Notes

§9Field maintenance record

Flush history (this phone)

Same order as the kit's one-page field record. Everything stays on this phone. Add this page to your home screen to use it offline.