Why Hospitality Needs a Dual Design

Two Streams, One Property

A hotel or resort draws borewell or municipal water that needs softening and often RO before it reaches guest rooms, laundry, kitchen, boiler, and pool — and it sends back sewage from rooms, kitchens, and banquet halls that has to be treated quietly, compactly, and without odour, since the plant usually sits close to guest-facing areas. Occupancy-driven peaks (check-in evenings, breakfast service, banquet events) mean both systems need headroom the average daily flow figure won't show.

At a Glance

Process Flow — Two Tracks, One Property

Guest-use water treatment (stages 1–2) runs alongside the STP train (stages 3–7). Scroll sideways on smaller screens.

Design Basis

Standard Inlet Characteristics

Typical raw water and sewage ranges we design around for hotel and resort properties.

Parameter	Typical Raw Inlet Range	Rispri Treated Target	Source Stream
pH (raw borewell/municipal water)	6.5 – 8.5	6.5 – 8.5	Guest-use supply
Total Hardness (as CaCO₃)	200 – 600 mg/L	< 60 mg/L (softened)	Guest-use, laundry, boiler feed
TDS (raw supply)	500 – 1,500 mg/L	< 100 mg/L (RO permeate)	Drinking, kitchen, laundry
Sewage pH	6.5 – 8.5	6.5 – 8.5	Rooms, kitchen, banquet
Sewage BOD	200 – 400 mg/L	< 10 mg/L (2019 NGT reuse norm)	Domestic sewage
Sewage COD	400 – 800 mg/L	< 50 mg/L	Domestic sewage
Sewage TSS	200 – 400 mg/L	< 10 mg/L	Domestic sewage
Oil & Grease (kitchen)	20 – 50 mg/L	< 10 mg/L	Kitchen & banquet washdown

Indicative values based on typical hospitality-sector water and sewage characteristics. Actual figures vary by occupancy, source water, and F&B intensity — confirmed through site water/effluent characterization during project scoping.

Compliance

STP Discharge & Reuse Standards

Sewage treatment standards tightened materially in recent years — a 2017 MoEF&CC gazette notification set differentiated norms by city size, and a 2019 National Green Tribunal order pushed several parameters tighter still.

Parameter	2017 Notification (Non-Metro)	2017 Notification (Metro)	2019 NGT Order
BOD	30 mg/L	20 mg/L	10 mg/L
COD	250 mg/L	—	50 mg/L
TSS	100 mg/L	50 mg/L	20 mg/L
Fecal Coliform	<1,000 MPN/100mL	—	<230 MPN/100mL
Ammonical-N	50 mg/L	—	5 mg/L
Total-N	—	—	10 mg/L

STPs commissioned above 10 KLD generation are commonly required to have a plant at all; capacity is typically sized roughly 20% above average daily flow with a 1.5–2.5× peak factor. Which of these norms binds your property depends on your STP's commissioning date, location, and SPCB consent conditions — treat this table as context for the conversation with your regulator, not a self-certifying checklist.

Process Design

The Treatment Process Rispri Follows

A softening/RO train for guest-use water, paired with a compact, low-odour STP sized for occupancy peaks.

01

Raw Water Filtration & Softening

Multi-media/sand filtration removes turbidity from borewell or municipal supply; ion-exchange softening protects the boiler, laundry, and pipework from scale. As a rough industry rule of thumb, water below ~60 ppm hardness is considered soft, 60–120 ppm hard, and above 120 ppm very hard — softening ahead of boilers, laundry, and cooling towers is standard practice at the harder end of that range.

02

RO for Drinking & Kitchen Use

A dedicated RO train brings TDS down for drinking water points, kitchen use, and premium guest amenities.

03

Kitchen Grease Trap

Grease traps at kitchen and banquet drain lines capture oil and fat before it reaches the sewage collection network — the same protective logic as a dairy fat trap, sized to F&B covers rather than milk throughput.

04

STP Equalization

An equalization tank absorbs occupancy-driven peaks — morning check-out, breakfast service, banquet events — before biological treatment. Hotels are commonly estimated to generate sewage equal to roughly 80–90% of water consumed; a 100-room property might run 15–20 KLD, while a large full-service resort with heavy F&B can reach 60–120 KLD.

05

MBBR / SBR Biological Treatment

A compact, low-odour biological stage — MBBR or SBR is typically preferred for hotels over conventional activated sludge because moving-bed biofilm carriers fill 50–70% of tank volume without needing a large secondary clarifier or sludge-recycle pumping, giving roughly 30–40% smaller footprint for comparable treatment. Design loading commonly runs 7–10 g BOD/m²·day at moderate temperatures, with rates derating meaningfully below 10°C — rarely a concern for Indian hospitality sites, but relevant for hill-station properties.

06

Clarification, Filtration & Disinfection

Secondary clarifier settles biomass; pressure sand and activated carbon filtration polish colour and odour, followed by chlorination or UV disinfection toward the BOD <10 mg/L, fecal coliform <230 MPN/100mL band the 2019 NGT order sets for treated sewage.

07

Treated Water Reuse

Treated sewage is routed to gardening, flushing, and cooling tower makeup — reducing freshwater draw and discharge volume across the property. Some Indian hotel installations have documented recycling upward of 90% of treated water back into on-site use once the loop is fully built out.

Reference Points

What Larger Indian Hotel Chains Have Built

A handful of publicly reported installations give a useful sense of scale and ambition, even though every property's design should start from its own water balance rather than copying another site's numbers:

Taj Palace, New Delhi: an MBR-based STP upgraded to 450 KLD capacity, supplying treated water to cooling towers, horticulture, and toilets through a dedicated pipeline; a separate laundry water recycling system reportedly saves around 80 KL/day.
Taj Mahal, New Delhi: a chemical-free water recycling system reported to save roughly 60,000 litres/day, with a stated 97% recycling efficiency and 92% of treated water reused on-site.
Taj Surajkund Resort & Spa: combined sewage/effluent treatment capacity of 350 KLD, with treated water reused for cooling towers and irrigation alongside rainwater recharge pits.
ITC Hotels: ITC Mughal (Agra) and ITC Rajputana (Jaipur) have achieved LEED Zero Water certification, with company-wide reporting of treating and recycling essentially all wastewater for landscaping, flushing, and cooling towers.

The consistent pattern across all four: treated water isn't discharged and forgotten — it's piped back into cooling, landscaping, and flushing as a designed second water loop, not a compliance afterthought.

Frequently Asked Questions

Does every hotel need an STP, or only larger properties?

Sewage treatment plants are commonly mandated above a 10 KLD generation threshold under CPCB/SPCB norms, which most full-service hotels above roughly 30–40 rooms will exceed. Smaller guesthouses may fall under septic tank/soak pit norms instead — worth confirming with your SPCB rather than assuming based on room count alone.

Why MBBR/SBR instead of a conventional activated sludge plant?

Footprint and odour control are the two practical reasons cited consistently across engineering sources — MBBR/SBR needs less land, doesn't require a large open clarifier near guest areas, and tolerates the swingy, peak-and-trough loading pattern of hotel occupancy better than a conventional ASP tuned for steady flow.

Can treated STP water really be used in guest-facing areas like pools or fountains?

Treated water meeting reuse-grade quality is routinely used for gardening, flushing, and cooling makeup — those are non-contact or landscaping applications. Guest-contact water (pools, drinking points) is treated as a completely separate, higher-standard loop (softening/RO on fresh water), not blended with recycled sewage.

Sources: Frontiers in Environmental Science — India's evolving STP discharge standards, Hotelier India — Taj Mahal Delhi water recycling, ITC Hotels sustainability reporting, MBBR process design reference (CED Engineering). Occupancy-based flow estimates and hardness bands are industry rules of thumb rather than a single authoritative published standard — confirmed against your property's actual metered consumption during design. The "BIS 2490" reuse-standard label is widely used in industry marketing but could not be independently verified against a primary BIS document in this research pass; the 2017/2019 CPCB-linked figures above are the better-sourced reference.

Why This Matters for Hospitality

Compact, low-odour footprint suited to guest-facing properties
Sized for occupancy peaks, not just average daily flow
Protects boiler, laundry, and pipework from scale via softening
Designed to 2019 NGT reuse norms and CPCB/SPCB discharge standards

Typical Plant Configuration

Softening + RO train sized to guest-use, laundry, and boiler demand
MBBR/SBR-based STP sized to peak occupancy flow
Grease traps at kitchen and banquet drain lines
Treated water storage for garden/flush/cooling reuse

Water Treatment for Hotels & Resorts