Room count alone is not a design flow. Two hotels with the same number of rooms can produce different wastewater profiles because occupancy, restaurants, laundry, pools, staff facilities and event spaces operate on different schedules. A useful enquiry separates measured water use from assumptions, records the busiest periods and identifies every stream that will enter the treatment plant.
1. Build an occupancy calendar, not a single headcount
List rooms available, rooms occupied, guests, resident staff, day staff and event visitors for representative low, normal and peak periods. Record the dates behind each figure and whether the property closes seasonally. Include check-in and check-out patterns because showers, kitchens and housekeeping may create concentrated morning or evening loads even when the daily total appears moderate.
Separate accommodation from restaurants, bars, banquet rooms, staff canteens, spa areas, public toilets and on-site residences. The Environment Agency guidance for commercial properties states that all sources of flow need to be added. Local rules and approved design methods remain controlling; a value from another jurisdiction should not be copied into a project without review.
2. Convert utility records into a hydraulic profile
Provide daily water-meter readings for the longest representative period available, preferably including the busiest season. Note irrigation, cooling, pool make-up and other water uses that do not enter the sewer, then identify unmetered sources that do. If an influent flow meter exists, export hourly data rather than only monthly bills. Mark missing readings, maintenance days, leaks and abnormal events instead of silently averaging them.
For each selected day, report total volume, highest hourly inflow, peak duration and the time between peaks. Record pump or lift-station batch volumes and discharge intervals. EPA explains that large hydraulic changes can overwhelm biological units and alter wastewater characteristics. Also check whether rainfall, groundwater or surface drainage enters the sewer; wet-weather inflow should not be confused with guest-generated sewage.
3. Pair flow with strength, equalization and operating duties
Take representative composite or timed samples where possible and report BOD₅, COD, suspended solids, ammonia, total nitrogen, phosphorus, pH, temperature, fats and oils when relevant. State the sampling point, date, occupancy and operating conditions. Kitchen grease, concentrated cleaning chemicals and laundry discharges can affect treatment even when their volume is small, so describe pretreatment and chemical-use practices.
Send the required effluent limits, discharge or reuse destination, available equalization volume, operating hours, power reliability, sludge-removal access and operator coverage. BOKAWATER publishes packaged domestic sewage equipment families, but catalog daily capacity alone does not select a model. Final sizing must reconcile the verified flow profile, pollutant load, local acceptance criteria and the supplier's confirmed scope.
Data to collect before comparing proposals
| Parameter / interface | Unit / format | Why it matters |
|---|---|---|
| Rooms and occupancy | Rooms; guests/day | Provide low, normal and peak dates, plus staff and event visitors. |
| Metered water use | m³/day by date | Separate sewer-bound use from irrigation, pool make-up and cooling. |
| Peak hourly inflow | m³/h and duration | Attach hourly meter or lift-station records and identify batch discharges. |
| Kitchen and banquet activity | Meals/day; event schedule | Record grease control, cleaning periods and exceptional events. |
| Laundry operation | kg/day or loads/day | State whether laundry is on site and when machines discharge. |
| Influent quality | mg/L; pH; °C | Attach dated results and the occupancy represented by each sample. |
| Season and wet weather | Calendar; rainfall notes | Identify closures, restart periods, infiltration and storm connections. |
| Equalization and utilities | m³; hours; kW | Provide usable tank volume, power availability, access and operator coverage. |
Technical references
- US EPA — Peak flows at sewage treatment plants ↗Source checked:
Evidence scope — original English record
Peak flows and inflow or infiltration can overwhelm biological treatment and change wastewater characteristics; hydraulic peaks must be documented separately.
- Environment Agency — SR2025 No 5 guidance ↗Source checked:
Evidence scope — original English record
For hotels and other commercial properties, all sources of wastewater flow must be identified and added; requirements depend on the project jurisdiction.
- BOKAWATER — Solar integrated domestic sewage treatment system ↗Source checked:
Evidence scope — original English record
Identifies an existing BOKAWATER packaged domestic sewage family and catalog capacities; this article does not select a model or promise performance.