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What are GPCB discharge limits for pH, COD, BOD and TDS?

By Harshal Mistry, Founder, MISTR Systems · 7 min read · Updated October 2026 · For plant owners, EHS officers and ETP operators in India

GPCBDischarge limitsCODBODTDS

Quick answer

Your legal limits are the ones written in your unit's consent (CCA) from GPCB, so start there. As a reference, India's general standards for discharge to inland surface water are pH 5.5–9.0, BOD 30 mg/L and COD 250 mg/L. BOD limits are looser for sewers (350 mg/L) and irrigation (100 mg/L). TDS is not part of the general table; where it applies, 2,100 mg/L of inorganic dissolved solids is the commonly used limit. Industry-specific standards, CETP inlet norms and zero liquid discharge conditions can all replace these numbers.

The general standards

Schedule VI of the Environment (Protection) Rules, 1986 sets the general standards for effluent discharge across India. GPCB applies them, together with any industry-specific standards, when it writes the conditions in your consent. The limit depends on where your treated effluent goes.

General standards for discharge of effluents, Environment (Protection) Rules, 1986, Schedule VI (maximum values, mg/L unless stated)
Parameter	Inland surface water	Public sewer	Land for irrigation	Marine coastal area
pH	5.5 – 9.0	5.5 – 9.0	5.5 – 9.0	5.5 – 9.0
BOD	30	350	100	100
COD	250	–	–	250
Suspended solids	100	600	200	100
Oil and grease	10	20	10	20

“–” means no general limit is set for that route; your consent may still set one.

BOD limit by discharge route

Inland surface water30 mg/L

Land for irrigation100 mg/L

Marine coastal area100 mg/L

Public sewer (with treatment downstream)350 mg/L

Source: Environment (Protection) Rules, 1986, Schedule VI. The stricter the route, the shorter the bar.

What each parameter tells you

pH shows how acidic or alkaline the effluent is. Outside 5.5–9.0 it harms aquatic life and corrodes pipes.
COD (chemical oxygen demand) is the oxygen needed to break down pollutants chemically. It is quick to measure and covers most organic load.
BOD (biochemical oxygen demand) is the oxygen bacteria use to break down the organic matter. In India it is measured over 3 days at 27 °C. BOD is normally lower than COD.
TDS (total dissolved solids) is the salt and mineral content left in the water. Treatment that removes COD and BOD often does little for TDS.

Why your consent may say something different

Industry-specific standards for sectors such as dyes, pharmaceuticals, textiles and chemicals can be stricter than the general table.
CETP members follow the inlet norms set for their Common Effluent Treatment Plant, not the final discharge limits.
Zero liquid discharge units may not be allowed to discharge at all.
Local conditions, such as a sensitive river or a polluted area, can lead to tighter limits.

So the table above is a reference, not your limit. Keep a copy of your CCA's effluent conditions next to the ETP log and the monitoring screen, so operators compare readings against the right numbers.

Questions plants ask

Are GPCB limits different from CPCB limits?

The general standards come from the Environment (Protection) Rules and apply across India. GPCB writes the limits for each unit into its consent, and these can be stricter than the national standards.

What is the TDS limit for industrial effluent?

TDS is not part of the Schedule VI general table. Where a limit applies, 2,100 mg/L of inorganic dissolved solids is the commonly used figure for inland surface water, sewers and irrigation. Your consent may set a different value.

We send effluent to a CETP. Which limits apply to us?

Your CETP's inlet norms and the conditions in your own consent. The CETP itself must then meet the discharge limits for its treated effluent.

ગુજરાતી સારાંશ

તમારી ડિસ્ચાર્જ મર્યાદા તમારા GPCB સંમતિપત્ર (CCA) માં લખેલી હોય છે, એટલે પહેલાં તે તપાસો. સામાન્ય ધોરણ મુજબ, સપાટીના પાણીમાં નિકાલ માટે pH 5.5 થી 9.0, BOD 30 mg/L અને COD 250 mg/L છે. CETP સભ્યો માટે CETP ની ઇનલેટ મર્યાદા લાગુ પડે છે.

See what your own data says

MISTR Systems checks whether your effluent monitoring data can be trusted. Try it with a free 15-day pilot: your own login, no hardware, and a pilot report at the end.

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Sources

This guide is general information, not legal advice. Always follow the directions issued to your unit by CPCB and your State Pollution Control Board.