Cost per Data Point: Colilert vs. Lume

Each Colilert sample requires reagents, labor, a vehicle trip, and lab processing — costs that multiply with every sample and site. Lume provides continuous, automated tryptophan-like fluorescence (TLF) monitoring as a complementary screening layer — not a regulatory replacement for approved methods, but a way to dramatically reduce the number of costly grab samples needed while catching contamination events in real time. The result: fewer truck rolls, faster response to water quality changes, and 24/7 visibility between scheduled compliance samples.

Colilert (IDEXX)

Grab-sample E. coli — consumables + labor

Sampling Frequency

Samples per site per month ?How many grab samples a technician collects per site each month. 4/mo (~1×/wk) is typical for routine monitoring.

Consumables per Sample

Reagent snap pack

Quanti-Tray

Vessel + thio

Other (gloves, labels, ice)

Colilert-Only Time (min)

Collect

Lab ?Time to add reagent, seal Quanti-Tray, and load incubator per sample.

Read

Breakdown (per sample)

Consumables—

Labor—

Vehicle—

Cost per Sample—

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Cost per Colilert Sample

Shared Parameters

Monitored sites

Labor

Rate ($/hr) ?Fully loaded labor rate including salary, benefits, overhead, and employer taxes.

Site Visit

Drive time (min, RT)

Mileage ($/mi) ?IRS standard mileage rate covers gas, depreciation, insurance, and maintenance.

RT (mi)

Head-to-Head Comparison

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Cost savings per data point

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More data points annually

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Annual savings

Sources & Assumptions ▾

Colilert consumables: Reagent snap pack $13.26/test, Quanti-Tray $4.62/tray (Fisher Scientific list prices).
Labor: $55/hr fully-loaded rate incl. salary, benefits, and employer taxes.
Vehicle: IRS standard mileage rate ($0.67/mi, 2024).
Lume: Subscription pricing, all-inclusive hardware + cloud + support. 1×/mo maintenance visit default.
Methodology: Per-sample Colilert cost × monthly frequency × 12 mo vs. Lume monthly subscription × 12 mo.

Lume Continuous Monitoring

Automated TLF sensor — no consumables, no lab

Subscription

Monthly cost ($/site) ?All-inclusive subscription covering hardware, cellular connectivity, cloud dashboard, and support.

Sampling Frequency

Readings per day 24

Days per month

Maintenance

Site visits / month

Visit time (min)

Breakdown (per site/mo)

Subscription—

Maintenance labor—

Vehicle—

Consumables$0.00

Per site / month—

Readings / month—

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Cost per Lume Reading