State of Tamil Nadu v. State of Kerala & Anr.

Judgment

carefully considered the provisions of amended 2003 Act and, in our view, in whatever way 2003 Act'is seen, there was no impediment for this Court to consider and decide the question whether raising the water level from 136 ft to 142 ft. would jeopardize the safety of the dam. This Court answered the question based on the materials on record, in the negative. The judgment of this Court in Mullaperiyar Environmental

[R.M. LODHA, CJI.] Protection Forum¹ by no stretch of imagination can be termed as per incuriam. The judgment wholly and squarely binds the parties including Kerala.

131. The Kerala legislature amended the 2003 Act by 2006 (Amendment) Act. By the 2006 (Amendment) Act, in Section 2, clauses Oa) and Ob) defining "custodian" and "dam" were inserted after clause 0). Clause (ala) defining "scheduled dam" was also inserted after clause (al). In sub-section (1) of Section 57 of the principal Act, the words "surveillance, inspection" were substituted by "ensuring the safety and security". The explanation in sub-section (2) of Section 57 was deleted. Section 62 of the principal Act was substituted by new Section 62. The new Section 62, inter alia, empowers the Dam Safety Authority with following functions:

"(¹) xxx xxx xxx (a) to evaluate the safety and security of all dams in the State considering among other factors, the age of the structures, geological and seismic factors, degeneration or degradation caused over time or otherwise;

(b) to (d) xxx xxx xxx (e) to direct the custodian to suspend the functioning of any dam, to decommission any dam or restrict the functioning of any dam if public safety or threat to human life or property so requires;

(f) to advise the Government, custodian, or other agencies about policies and procedures to be followed in site investigation, design, construction, operation and maintenance of dams;

(g) to conduct studies, inspect and advise the custodian or any other agency on the advisability of raising or lowering of the maximum water level or full reservoir level of any dam, not being a scheduled dam, taking into account the safety of the dam concerned;

(h) to⁰) )()(){ )()(){ xxX'

132. The functions conferred on the Dam Safety Authority

under new Section 62 override the judgment, decree or order of any Court or any treaty, agreement, contract, instrument or any other document. Su.b-section (3) of new Section 62 provides that where a direction is issued by the Dam Safety Authority under sub-Section (1 ), the custodian or any other agency to whom it is directed shall take immediate measures within the time frame stipulated by the Authority or do or refrain from doing such things within such time frame as may be stipulated and to comply with the directions of the Authority. After Section 62, new Sections 62A and 628 have been added. The details of the dams which are endangered on account of their age, degeneration, degradation, structural or other impediments are specified in the Second Schedule. Sub-sections (2) and (3) to new Section 62A are overriding provisions, which read as under:

"(1) )()(){ )()(){ )()(){ (2) Notwithstanding anything contained in any other law or in any judgment, decree, order or direction of any court, or any treaty. contract, agreement, instrument or document, no Government, custodian or any other agency shall increase, augment, add to or expand the Full Reservoir Level Fixed or in any other way do or omit to do any act with a view to increase the water level fixed and set out in THE SECOND SCHEDULE. Such level shall not be altered except in accordance with the provisions of this Act in respect .of any Scheduled dam.

(3) Notwithstanding anything contained in any other law, or in any judgment, decree, order, direction of any court or any treaty, contract, agreement, instrument or document, [R.M. LODHA, CJI.] any Government, custodian or any other agency intending to, or having secured any right under any treaty, contract, agreement, instrument or document or by any other means to increase, augment, add to or expand, the storage capacity or increase the Full Reservoir Level Fixed of any Scheduled dam, shall not do any act or work for such purpose without seeking prior consent in writing of the Authority and without. obtaining an order permitting such work by the Authority.

(4) and (5) xxx xxx xxX'

133. Section 628 gives powers of a Civil Court to the Dam Safety Authority in respect of the matters specified therein while dea~ng with applications for consent in writing for increasing, augmenting, adding to or expanding the storage capacity or the water spread area or for increasing of Maximum Water Level or Full Reservoir Level fixed for Scheduled dams. Section 68A bars the jurisdiction of Civil Court from settling, deciding or dealing with any question of fact or to determine any matter which under the 2003 Act, as amended by 2006 (Amendment) Act, is required to be settled, decided or dealt with or to be determined by the Authority under the Act. In Second Schedule, at item No.1 is the subject "Mullaperiyar Dam" for which FRL is fixed at 41.45 meter (136 ft.) from the deepest point of the level of Periyar river at the site of the main dam.

134. Tamil Nadu says that 2006 (Amendment) Act to the · F extent it applies to Mullaperiyar dam seeks to nullify the judgment of this Court in Mullaperiyar Environmental Protection Forum¹ by declaring the dam to be endangered and by fixing the height of the water level at 136 ft.; that It authorizes the Dam Safety Authority to disregaFd the judgment and to adjudge for itself whether to allow raising of water level and Section 62(1)(e) authorizes the Dam Safety Authority to order inter a/ia decommissioning of the dam despite the finding of safety recorded by this Court in the 2006 judgment and, thus, the 2006 (Amendment) Act is unconstitutional being violative of separation of powers doctrine and consequently rule of law.

135. On the other hand, the argument of Mr. Harish N. Salve, learned senior counsel for Kerala, is that the legislature of every State has not just the power but.the obligation to take appropriate legislative measures to ensure the safety and security of its residents. Where the legislature of a State is satisfied that there is a need to curtail the use or storage of a water reservoir to protect its citizenry and elects to enact legislation as a precautionary measure, the legislation cannot

be said to be in excess of the legislative competence of the State if it relates to reservoir and dam within the legislating

State. Kerala legislature has imposed precautionary measures by placing pro tern restrictions on the storage level of the dams mentioned in the Second Schedule read with Section 62A(2)

of the 2006 (Amendment) Act and the said restrictions are based on the legislative wisdom of the Kerala legislature that

these dams are endangered on account of their age, degeneration, degradation, structural or other impediments. While adjudicating upon the constitutional validity, Mr. Harish

Salve argues that the Court must proceed on the premise that the legislature understands and correctly appreciates the needs

of its own people and its laws are directed to the problems made manifest by its experience and are based on adequate grounds.

136. Mr. Harish N. Salve, learned senior counsel for Kerala heavily relies upon 'precautionary principle' and 'public trust doctrine' and argues that Kerala legislature was competent to override the contracts and regulate safety of the Mullaperiyar

dam situated within its territory across river Periyar. His submission is that the State as sovereign retains continuing

supervisory control over navigable waters and underlying beds. It is his submission that the State has a duty of 'continuing supervision' even after such rights have been granted. In this regard strong reliance is placed by him on Pfizer Animal Health²⁷• [R.M. LODHA, CJI.] 137. In Pfizer Animal Health²⁷ the Court of First Instance

, of European Communities (Third Chamber) was concerned with the legality and validity of the regulations which, inter alia, banned particular use of the substance in question. Pfizer argued that it was directly concerned by the contested regulation as it withdraws authorization of Virginiamycin. The counsei for the European Union argued that the regulations were enacted to general application which was applicable to objectively determined situations and that they ban the particular use of the substance in question, whether they are marketed by Pfizer or by any one else under a different name. The Court observed that for the purpose of taking preventive action, to wait for the adverse effects of the use of the products was not required.

138. Dealing with precautionary principle, the Court made these observations:

"First, it must be borne in mind that, when the precautionary principle is applied, the fact that there is scientific uncertainty and that it is impossible to carry out a full risk assessment in the time available does not prevent the competent public authority from taking preventive protective measures if such measures appear essential, regard being had to the level of risk to human health which the public authority has decided is the critical threshold above which it is necessary to take preventive measures. The precautionary principle allows the competent public authority to take, on a provisional basis, preventive protective measures on what is as yet an incomplete scientific basis, pending the availability of additional scientific evidence.

It is not for the Court to assess the merits of either of the scientific points of view argued before it and to substitute its assessment for that of the Community institutions, on which the Treaty confers sole responsibility in that regard.

139. Kerala has also relied upon the article, "The Public Trust Doctrine in the Water Rights Context" by Roderick E. Wa/ston²² The author has culled out following four principles

• of the Public Trust doctrine:

"(1) The state as sovereign "retains continuing supervisory control" over navigable waters and underlying beds; (2) The legislature, either directly or through the water rights agency, has the right to grant usufructuary water rights even though such rights will "not promote, and may unavoidably harm, the trust uses at the sources stream;" (3) The state has the "affirmative duty" to take the public trust into account in planning and allocating water resources; and (4) The state has a "duty of continuing supervision" over water rights even after such rights have been granted."

139.1 Public trust doctrine, Roderick E. Walston says, is regarded by some as an exercise of sovereign state regulatory, analogous to the police power.

140. In our opinion, the principle of 'public trust doctrine' in the context of water rights culled out by Roderick E. Walston or the 'precautionary principle' explained in Pfizer Animal Health²⁷ can hardly be doubted but these principles have no application in the context of safety of Mullaper~yar dam on raising the water level from the present level to 142 ft., which was directly in issue and has been expressly, categorically and

[R.M. LODHA, CJI.] unambiguously determined by the Court. This Court has found - supported by the Expert Committee Reports - that the safety of the subject dam is not at all jeopardized if the water level is raised from the present level to 142 ft. Kerala, which is contesting party, by applying 'public trust doctrine' or 'precautionary measure', cannot through legislation do an act in conflict with the judgment of the highest Court which has attained finality. If a legislation is found to have breached the established constitutional limitation such as separation of powers, it has to go and cannot be allowed to remain.

141. It is true that the State's sovereign interests provide the fouHdation of the public trust doctrine but the judicial function is also a very important sovereign function of the State and the . foundation of the rule of law. The legislature cannot by invoking 'public trust doctrine' or 'precautionary principle' indirectly control the action of the Courts and directly or indirectly set aside the authoritative and binding finding of fact by the Court, particularly, in situations where the executive branch {Government of the State) was a party in the Htigation and the final judgment was delivered after hearing them.

142. 2006 (Amendment) Act in its application to and effect on the Mullaperiyar dam seeks to attain the following:

{a) It substitutes Section 62 with a new provision whereby, notwithstanding the judgment of this Court and notwithstanding anything contained in any treaty, contract, 1886 Lease Agreement and 1970 supplemental agreements, the function of evaluation of safety of the Mullaperiyar dam and the power to issue directions to Tamil Nadu as custodian are conferred upon Dam Safety Authority~

(b) the Dam Safety Authority is empowered, inter alia, to restrict the functioning of Mullaperiyar dam and/or to conduct studies on the advisability of raising or lowering of the m'aximum water level or the full reservoir level;

(c) Mullaperiyar dam is considered by Kerala legislature

to be endangered and by virtue of Section 62(A), it takes away . the right of Tamil Nadu to increase, expand the FRL or in any

manner increase the water level as set out in the Second Schedule except in accordance with the provisions of the Act; (d) under Section 62A(4), Tamil Nadu as custodian has to submit an application to the Dam Safety Authority for its prior consent for the increase in the water level;

(e) it takes away all rights of Tamil Nadu including the right which has passed into judgment of this Court to increase the

water level;

(f) the Dams Safety Authority has power to order de commissioning of the Mullaperiyar dam.

143. This Court in Mullaperiyar Environmental Protection Forum¹ after hearing the State of Kerala, was not persuaded , by Kerala's argument that Mullaperiyar dam was unsafe or storage of water in that dam cannot be increased. Rather, it

permitted Tamil Nadu to increase the present water level from 136 ft. to 142 ft. and restrained Kerala from interfering in Tamil

Nadu's right in increasing the water level in Mullaperiyar dam to 142 ft. Thus, a judgment has been given by this court in contest between the two States in respect of safety of

Mullaperiyar dam for raising water level to 142 ft. The essential element of the judicial function is the decision of a dispute

actually arising between the parties and brought before the court. Necessarily, such decision must be binding upon the parties and enforceable according to the decision. A plain and

simple judicial decision on fact cannot be altered by a legislative decision by employing doctrines or principles such

as 'public trust doctrine', 'precautionary principle' 'larger safety principle' and, 'competence of the State legislature to override agreements between the two States'. The Constitutional

principle that the legislature can render judicial decision ineffective by enacting validating law within its legislative field fundamentally altering or changing its character retrospectively has no application where a judicial decision has been rendered by recording a finding of fact. Under the pretence of power, the legislature, ·cannot neutralize the effect of the judgment given after ascertainment of fact by means of evidence/materials placed by the parties to the dispute. A decision which disposes of the matter by giving findings upon the facts is not open to change by legislature. A final judgment, once rendered, operates and remains in force until altered by the court in appropriate proceedings.

144. 2006 (Amendment) Act plainly seeks to nullify the judgment of this court which is constitutionally impermissible. Moreover, it is not disputed by Kerala that 2006 (Amendment) Act is not a validation enactment. Since the impugned law is not a validating law, it is not required to inquire whether in making the validation the legislature has removed the defect which the Court has found in existing law. The 2006 {Amendment) Act in its application to and effect on Mullaperiyar dam is a legislation other than substantially legislative as it is aimed at nullifying the prior and authoritative decision of this Court. The nub of the infringement consists in Kerala legislator's revising the final judgment of this Court in utter disregard of the constitutional principle that the revision of such final judgment must remain exclusively within the discretion of the court.

145. Section 62A declares the dam to be endangered. · F The Second Schedule appended to the Act fixes the height of the water level at 136 ft. though this Court in its judgment had declared Mul!aperiyar dam safe and permitted the increase of the water level to 142 ft. Moreover, the 2006 (Amendment) Act authorises the Dam Safety Authority to adjudge its safety to allow raising of water level. The provision is in direct disregard of the judgment of this Court. Section 62A also freezes all work on the dam allowed by this Court in its judgment dated 27.2.2006. In our opinion, by 2006 (Amendment) Act, the Kerala legislature has overturned a final judgment in the interest of its own executive Government. The impugned law amounts

to reversal of the judgment of this Court which determines directly the question of safety of Mullaperiyar dam for raising water level to 142 ft. and whereunder Tamil Nadu's legal right has beeri determined.

146. On behalf of Kerala, it is strenuously argued by Mr. Harish Salve that right to safety of the people being a public right could not have passed into 2006 judgment of this court.

In this regard, heavy reliance is placed on the majority decision of the Wheeling Bridge²⁹ Firstly, public right qualification in

• Wheeling Bridge²⁹ has no application in the present case as there is a critical difference between the provisions impugned before us and the provisions which were impugned before US Supreme Court in Wheeling Bridge²⁹ The principle question •

before the US Supreme Court in Wheeling Bridge²⁹ was whether or not the compact could operate as a restriction upon

the power of courts under the Constitution to regulate commerce among several States. In response to the argument urged before it that the Congress cannot have the effect to annul

the judgment of the court already rendered or the rights determined thereby was accepted as a general proposition but

this proposition was held not applicable in the matters of adjudication upon the public rights. In our view, a legislation violating the separation of powers principle cannot be saved

by carving out an exception that the legislature has regulated a public right, We think that the act of legislature designed to

achieve a legitimate regulatory measure does not grant constitutional immunity to such law enacted in violation of separation of powers principle or in other words, rule of law.

Once a judicial decision on ascertainment of a particular fact achieves finality, we are afraid the legislature cannot reopen

such final judgment directly or indirectly. In such cases, the courts, if brought before them, may reopen such cases in exercise of their own discretion.

147. In our view, Wheeling Bridge²⁹ qualification by the

[R.M. LODHA, CJI.] majority decision of U.S. Supreme Court cannot be read to permit the actual revision of the final judgment by the legislature. If Wheeling Bridge2⁹ lays down the proposition that a judgment declaring a public right may be annulled by subsequent legislation as contended by Mr. Harish Salve, then we say, as we must, that we are not persuaded to accept such proposition of majority judgment in Wheeling Bridge²⁹ The two separate

• opinions in Wheeling Bridge²⁹ one by Mclean J. and the other by Wayne J. - though in minority- also did not accept such proposition.

148. The above discussion must also answer the argument of Mr. Harish Salve that rules of inter partes litigation do not determine the obligation of the State for safety of its people. We do not think it is necessary to consider the opinion of Weeramantry, J. in Gobcikovo-Nagymaros Project (ICJ) in detail. The stress laid by Weeramantry, J. is that where issue of serious or catastrophic environmental danger arises, the Court must look beyond inter partes adversarial procedures.

149. It is true that safety of dam is an aspect which can change from time to time in different circumstances but then the circumstances have to be shown based on which it becomes necessary to make departure from the earlier finding. It is always open to any of the parties to approach the court and apply for re-assessing the safety aspect but absent change in · circumstances, factual determination in the earlier proceedings even on the questions such as safety of dam binds the parties. If the circumstances have changed which necessitates a re-look on the aspect of safety, the Court itself may exercise its discretion to reopen such case but legislative abrogation of judgment for even the very best of reasons and genuine concern for public safety does not clothe the legislature to rescind the judgment of the court by a legislation.

150. The contention of Mr. Harish Salve that by declaring dam unsafe, the legislature has not rendered any finding of fact; it deems dam unsafe and sets up an Authority to regulate it, is

t? noted b~ rejected. What has been found as a fact by judicial

det~rmmatron cannot be declared otherwise by applying legal fiction. We are, however, persuaded to accept the submission of Mr. Vinod Bobde, learned senior counsel for Tamil Nadu that

the fact that the Mullaperiyar dam is safe was found by this Court and that finding of fact can never be deemed to be

imaginary by a legal fiction which then proceeds to deem the opposite to be real, viz., that the dam is endangered. This is

not a matter of legislative policy as it is being made out to be, rather in our opinion, it is incursion in the judicial process and functions of judicial organ. The declaration in Section 62A read with item No. 1 of the Second Schedule leaves no manner of

doubt that the enactment is intended to reach the question decided by the Court.

151. The question whether or not the legislature has usurped the judicial power or enacted a law in breach of

separation of powers principle would depend on facts of each case after considering the real effect of law on a judgment or a judicial proceeding. One of the tests for determining whether

a judgment is nullified is to see whether the law and the judgment are inconsistent and irreconcilable so that both cannot stand

together. In what we have already discussed above, it is abundantly clear that on the one hand there is a finding of fact determined by this Court on hearing the parties on the basis

of the evidence/materials placed on record in the judgment·of this Court in Mul/aperiyar Environmental Protection Forum1

and on the other in 2006 (Amendment) Act, the Kerala legislature has declared the dam being an endangered one and fixed the water level in the dam at 136 ft. If the judgment of this

Court in Mul/aperiyar Environmental Protection Forum1 ar.d the 2006 (Amendment) Act are placed side by side insofar as

safety of the Mullaperiyar dam for raising the water level from 136 ft. to 142 ft. is concerned, it is obvious that the judgment of this Court and the law enacted by Kerala State legislature

cannot stand together and they are irreconcilable and inconsistent. The impugned law is a classic case of nullification of a judgment simpliciter, as in the judgment of this Court the question of safety of dam was determined on the basis of materials placed before it and not on the interpretation of any existing law and there was no occasion for the legislature to amend the law by altering the basis on which the judgment was founded. When the impugned law is not a validation law, there is no question of the legislature removing the defect, as the Court has not found any vice in the existing law and declared such law to be bad.

152. There is yet another facet that in federal disputes, the legislature (Parliament and State legislatures) cannot be judge in their own cause in the case of any dispute with another State. The rule of law which is basic feature of our Constitution forbids the Union and the States from deciding, by law, a dispute between two States or between the Union and one or more States. If this was permitted under the Constitution, the Union and the States which have any dispute between them inter se would enact law establishing its claim or right against the other and that would lead to contradictory and irreconcilable laws. The Constitution makers in order to obviate any likelihood of contradictory and irreconcilable laws being enacted has provided for independent adjudication of federal disputes. Article 131 of the Constitution confers original jurisdiction upon this Court in relation to the disputes between the Government of India and one or more States or between the Government .of India and any State or States on one side and one or more States on the other or between two or more States insofar as dispute involves any question on which the existence or extent of a legal right depends. The proviso appended to Article 131 carves out an exception to the jurisdiction of this Court to a dispute arising out of treaty, agreement, covenant, engagement, sanad or other similar instrument which have been entered into or executed before the commencement of the Constitution and continues in operation after such commencement, which are political in nature. In .relation to dispute relating to waters of inter-State river or river valleys, Article 262 provides for creation of tribunal or forum for their

adjudication. In federal disputes, Parliament or State legislatures by law, if seek to decide a dispute between the two States or between the Union and one or more States directly

or indirectly, the adjudicatory mechanism provided in Articles 131 and 262 of the Constitution would be rendered nugatory

and, therefore, such legislation cannot be constitutionally countenanced being violative of separation of powers doctrine.

153. Mr. Harish Salve, learned senior couns~ is right in his submission that a legislation can never be challenged on

the principles of res judicata and that it binds a party and not the legislature. The question here is not that the 2006

(Amendment) Act is unconstitutional on the ground of res judicata but the question is, when a categorical finding has been

recorded by this Court in the earli~r judgment that the dam is safe for raising the water level to 142 ft. and permitted the water

lever of the dam being raised to 142 ft. and that judgment has become final and binding between the parties, has the Kerala legislature infringed the separation of powers doctrine in

enacting such law? In what has already been discussed above, the answer to the question has to be in the affirmative and we

hold so.

154. Where a dispute between two States has already

been adjudicated upon by this Court, which it is empowered _to deal with, any unilateral law enacted by one of the parties

that results in overturning the final judgment is bad not because it is affected by the principles of res judicata but because it infringes the doctrine of separation of powers and rule of law,

as by such_ law, the legislature has clearly usurped the judicial power.

Res-judicata 155. It is true that 2006 judgment was rendered in exercise

of the jurisdiction of this Court under Article 32 of the Constitution and the petitions which were transferred to this

[R.M. LODHA, CJ1.] Court under Article 139A but to say that such judgment does not bind this Court while deciding the present suit, which confers exclusive jurisdiction upon it, is not correct. The earlier decision of this Court by no stretch of imagination can be regarded as a judgment rendered without jurisdiction. A finding recorded by this Court in the proceedings under Article 32 is as effective and final as in any other proceedings.

156. The ~ule of resjudicata is not merely a technical rule but it is based on high public policy. The rule embodies a principle of public policy, which in turn, is an essential part of the rule of law. In Duchess of Kingston⁶² the House of Lords

, (1n the opinion of Sir William de Grey) has observed: "From the variety of cases relative to judgments being given in evidence in civil suits, these two deductions seem to follow as generally true: first, that the judgment of a court of concurrent jurisdiction, directly upon the point, is as a plea, a bar, or as evidence, conclusive, between the· same parties, upon the same matter, directly in question in another court; secondly, that the judgment of a court of exclusive jurisdiction, directly upon the point, is, in like manner, conclusive upon the same matter, between the same parties, coming incidentally in question in another court, for a different purpose."

157. Corpus Juris explains that res judicata is a rule of universal law pervading every well-regulated system of jurisprudence, and is put upon two grounds, embodied in various maxim_s of the common law; the one, public policy and necessity, which makes it to the interest of the State that there should be an end to litigation; and the other, the hardship on the individual that he should be vexed twice for the same cause.

158. In Sheoparsan Singh⁶³ Sir Lawrence Jenkins noted

, the statement of law declared by Lord Coke, 'interest reipublica ut sit finis litium,' otherNise great oppression might be done

under colour and pretence of law. - (6 Coke, 9A.) 159. In Daryao⁶⁴ P.B. Gajendragadkar, J. while explaining , the rule of res judicata stated that on general considerations

of public policy there seems to be no reason why rule of res judicata should be treated as inadmissible or irrelevant while

dealing with the petitions filed under Article 32 of the Constitution. P.B. Gajendragadkar, J. referred to earlier

decision of this Court in M.S.M. Sharma⁶⁵ wherein the application of the rule of res judicata to a petition filed under

Article 32 was considered and it was observed that the question determined by the previous decision of this Court cannot be reopened and must govern the rights and obligations of the parties which are subsequently the same.

160. In Guiab Chand Chhota/al Parikh⁶⁶ this Court stated , that a decision in a writ petition is res judicata in a subsequent suit.

161. In Nanak Singh⁶⁷ the question whether the decision in a writ petition operates as res judicata in a subsequent suit

filed on the same cause of action has been settled. In Nanak Singh⁶⁷ this court observed that there is no good reason to , preclude decisions on matters in controversy in writ proceedings under Article 226 or Article 32 of the Constitution

from operating as res judicata in subsequent regular suits on the same matters in controversy between the same parties and,

thus, to give limited effect to the principle of finality of decision after full contest.

162. Nanak Singh⁶⁷ has been followed by a three Judge

[R.M. LODHA, CJI.] Bench of this Court in Bua Das Kausha/6⁶ In our view, the rule

• of res judicata which is founded on public policy prevents not only a new decision in the subsequent suit but also prevents new investigation. It prevents the defendant from setting up a plea in a subsequent suit which was decided between the parties in the previous proceedings. The legal position with regard to rule of res judicata is fairly well-settled that the decision on a matter in controversy in writ proceeding {Article 226 or Article 32 of the Constitution) operates as res judicata in subsequent suit on the same matters in controversy between the same parties. For the applicability of rule of res judicata it is not necessary that the decision in the previous suit must be the decision in the suit so as to operate as res judicata in a subsequent suit. A decision in previous proceeding, like under Article 32 or Article 226 of the Constitution, which is not a suit, will be binding on the parties in the subsequent suit on the principle of res judicata.

163. For the applicability of rule of res judicata, the important thing that must be seen is that the matter was directly and substantially in issue in the previous proceeding and a decision has been given by the Court on that issue. A decision on issue of fact in the previous proceeding - such proceeding may not be in the nature of suit - constitutes res judicata in the subsequent suit.

164. In light of the above legal position, if the 2006 judgment is seen, it becomes apparent that after considering the contentions of the parties and examining the reports of Expert Committee, this Court posed the issue for determination about the safety of the dam to increase the water level to 142 ft. and came to a categorical finding that the dam was safe for raising the water level to 142 ft. and, accordingly, in the concluding paragraph the Court disposed of the writ petition and the connected matters by permitting the water level of Mullaperiyar dam being raised to 142 ft. and also permitted further strengthening of the dam as per the report of the Expert

Committee appointed by the CWC. The review petition filed against the said decision was dismissed by this Court on 27. 7.2006. The 2006 judgment having become final and

binding, the issues decided in the said proceedings definitely operate as res judicata in the suit filed under Article 131 of the

Constitution.

165. Shri Harish Salve, learned senior counsel for Kerala,

placed reliance upon the decision of this Court in N.D. Jayar⁹ In N.D. Jayar⁹ Dharmadhikari, J. made general observations

on the dam safety aspect that plea like res judicata on the earlier decisions passed by the Supreme Court cannot be allowed -to be raised. The observations made by Dharmadhikari, J. in N.D. Jaya/6⁹ have to be read as an

exception to the res judicata rule in the matters where, by their very nature, the factual situation has drastically changed in

course of time. If substantial changes in the circumstances occur and such circumstances are shown to the .Court necessitating departure from the earlier finding on the issue of safety, the

Court can be approached and in that event the Court itself may exercise its discretion to reopen the safety aspect having regard

to the drastic change in circumstances or in emergent situation as to the safety of dam. In our view, a judicial decision, having achieved finality, becomes the last word and can be reopened

in the changed circumstances by that Court alone and no one else.

166. On behalf of Kerala, it is contended that the jurisdiction of this Court under Article 32 of the Constitution for

enforcement of the fundamental rights conferred by Part Ill of the Constitution is ousted or excluded in respect of disputes

between two or more States: since such disputes fall within the ambit of the original jurisdiction of this Court under Article 131 of the Constitution or jurisdiction of a tribunal constituted under

[R.M. LODHA, CJI.] the provisions of Inter-State River Water Disputes Act, 1956 read with the provisions of Article 262 of the Constitution. Thus, it was submitted that the 2006 judgment is not binding and that the rule of res judicata can hardly be attracted in this situation.

167. We are unable to accept the submission of the learned senior counsel for Kerala. The label of jurisdiction exercised by this Court is not material for applicability of principles of res judicata if the matter in issue in the subsequent suit has already been concluded by the earlier decision of this Court between the same parties. The 2006 judgment was the result of judicial investigation, founded upon facts ascertained in the course of hearing. The plea of lack of jurisdiction of this Court was taken in the earlier proceedings on both the grounds, viz., (1) whether the jurisdiction of this Court is barred in view of Article 262 read with Section 11 of the Inter-State River Water Disputes Act, 1956, and (2) whether Article 363 of the Constitution bars the jurisdiction of this Court. On both these questions t.he findings were recorded against Kerala. It is too much for Kerala to say that the 2006 judgment is without jurisdiction. and not binding.

168. The rule of res judicata is articulated in Section 11⁷⁰ of the Code of Civil Procedure.

169. Explanations VII and VIII were inserted in the above provision by Code of Civil Procedure (Amendment) Act, 1976 w.e.f. 1.2.1977. Explanation VIII in this regard is quite relevant. The principles of res judicata, thus, have been made applicable to cases which are tried by Courts of limited jurisdiction. The decisions of the Courts of limited jurisdiction, insofar as such decisions are within the competence of the Courts of limited jurisdiction, operate as res judicata in a subsequent suit, although, the Court of limited jurisdiction that decided the previous suit may not be competent to try such subsequent suit or the suit in which such question is subsequently raised. If a decision of the Court of limited jurisdiction, which was within its competence, operates as res judicata in a subsequent suit even when the subsequent suit is not triable by it, a fortiori, the decision of the highest Court of the land in whatever jurisdiction given on an issue which was directly raised, considered and decided must operate as res judicata in the subsequent suit

[R.M. LODHA, CJI.] triable exclusively by the highest Court under Article 131 of the Constitution. Any other view in this regard will be inconsistent with the high public policy and rule of law. The judgment of this Court directly upon the point, is as a plea, a bar, or as evidence, conclusive between the same parties, upon the same matter, directly in question before this Court, though, label of jurisdiction is different.

170. The principles of res judicata are clearly attracted in the present case. The claim of Kerala in the earlier proceeding that water level cannot be raised from its present level of 136 ft. was expressly not accepted and the obstruction by Kerala to the water level in the Mullaperiyar dam being raised to 142 ft. on the ground of safety was found untenable. The judgment dated 27.2.2006 of this Court, thus, operates as res judicata in respect of the issue of safety of the dam by increasing its water level from 136 ft. to 142 ft.

171. It is argued by Mr. Harish Salve, learned senior counsel for Kerala, that even agreements entered into between foreign sovereigns can be overridden in exercise of legislative powers. He argues that if the contention of Tamil Nadu that the 1886 Lease Agreement. was an ordinary lease agreement is correct and assuming that such an agreement was continued, it clearly was open to the legislature of the State of Kerala to override such a contract. According to him, even contracts by way of sanads, treaties, etc., by the Crown could, after the Government of India Act and also after the Constitution of India, be overridden by exercise of the legislative power.

172. Learned senior counsel for Kerala in support of this contention relied upon the Privy Council decision in Thakur Jagannath Baksh¹⁹ and Maharaj Umeg Singh²⁰ Learned

• senior counsel also submits that Section 108 of the SR Act does not create any limitation upon Kerala exercising legislative power, inter a/ia, to cancel 1886 Lease Agreement and if Section 108 of SR Act is construed to impose a permanent fetter on the State's legislative power, such provision is

unconstitutional.

173. It may be stated immediately that the constitutionality of the SR Act has not been raised by Kerala in its written statement. As a matter of fact, there is no issue framed by the Court in this regard. Rather, in the earlier litigation the constitutionality of Section 108 of the SR Act was challenged. In the 2006 judgment, one of the questions framed for consideration was, whether Section 108 of the SR Act is

unconstitutional. The Court held that law making power under Articles 3 and 4 of the Constitution was paramount and it was

neither subjected nor fettered by Article 246 and Lists II (State List) and Ill (Concurrent List) of the Seventh Schedule. The Court also held that power of Parliament to make law under Articles

3 and 4 is plenary and traverses over all legislative subjects as are necessary for effecting a proper reorganization of the

States. Consequently, the Court found no merit in the challenge as to the validity of Section 108 of the SR Act.

174. We are, therefore, not persuaded to consider constitutional validity of Section 108(1) of the SR Act again.

Moreover, it is not necessary to consider this aspect in view of our finding that 2006 (Amendment) Act enacted by Kerala legislature is unconstitutional.

175. Thakur Jagannath Baksh¹⁹ and Maharaj Umeg Singh²⁰ have no application to the situation obtaining in the·

present case. The effect of a judgment which enforces a legal right flowing from a contract is that the right is incorporated as a right under the judgment and such a right cannot be

overridden by legislature as it tantamounts to overriding a judgment.

176. Learned senior counsel for Kerala also relied upon

a decision of this Court in State of Orissa⁷¹ In State of Orissa⁷¹ while dealing with Article 131, this Court stated, "Article 131 has no doubt given the Supreme Court exclusive jurisdiction to resolve any dispute between, inter alia, two or more States. This exclusive jurisdiction is, however, subject to two limitations one contained in the opening words of the Article, namely, "subject to the provisions of this Constitution" and the other which is contained in the proviso to the Article."

177. There is no doubt that the jurisdiction to resolve any dispute between two or more States is conferred upon the Supreme Court by Article 131 of the Constitution. However, it does not follow logically from this that a judgment rendered by the Supreme Court in a writ jurisdiction under Article 32 amongst others between two States is not conclusive and binding on such States. As already noted above, the 2006 judgment rendered by this Court in exercise of its jurisdiction under Article 32 binds Kerala and Tamil Nadu. We have no hesitation and we state with all emphasis that a finding recorded by this Court in exercise of jurisdiction under Article 32 is

a binding between the two parties, in subsequent suit between the two ·states under Article 131.

Safety of Mullaperiyar dam - Evidence and EC Report

178. Learned senior counsel for Kerala while assailing the finding of fact on safety of Mullaperiyar dam recorded in 2006 judgment, and in support of his contention that it does not constitute res judicata as the circumstances have changed, has relied upon the evidence of its witness Dr. A.K. Gosain (DW- 3) on the impact of Probable Maximum Flood (PMF), evidence of Dr. D.K. Paul on the impact of seismic forces and certain admissions of Tamil Nadu's witness PW-1. Mr. Harish Salve argues that the doctrine of finality does not preclude this Court from correcting the errors. Learned senior counsel in this regard places reliance upon three decisions of this Court in AR.

Antulay⁷² Isabella Johnson⁷³ and Rupa Ashok Hurra⁷⁴ , , . 179. Being the highest court of the land, this court possesses powers to correct a judgment in a curative petition if the parameters laid down in Rupa Ashok Hurra⁷⁴ are satisfied. The present case does not fall within the parameters laid down in Rupa Ashok Hurra⁷⁴ Though there is no .

justification to reopen the dam safety aspect in view of the judgment of this Court passed on 27.2.2006, yet for our

satisfaction as to whether there is any danger to the Mullaperiyar dam, despite strengthening of dam carried out by

Tamil Nadu in accordance with the strengthening measures ewe, suggested by we briefly intend to look into this aspect.

180. Learned senior counsel for Kerala submits that danger posed to the safety of the Mullaperiyar dam arises from,

(i) the impact of Probable Maximum Flood (PMF), i.e., floods which impact the dam; (ii) the impact of Maximum Considered Earthquake (MCE), i.e., if earthquake happens, the impact of

such event on the dam; and (iii) the impact on structural degeneration, i.e., with the age, the dam structure has been

rendered unsafe. Kerala's emphasis is that in the 2006 judgment this Court wrongly endorsed the PMF of 2.12 lakh ewe cusecs estimated by the in 1986. Kerala asserts that the

observed flood at Mullaperiyar dam in 1943 was 2.98 lakh cusecs and according to Tamil Nadu's own witness (PW-1), the

PMF ought to be more than observed flood. Hence, estimation of PMF as 2.12 lakh cusecs by the CWC in 1986 is an underestimation.

181. As regards impact of MCE, Kerala has heavily relied upon the study conducted by Dr. D.K. Paul and Dr. M.L.

Sharma, Professors of llT, Roorkee. Kerala says that these two

[R.M. LODHA, CJI.] experts have categorically concluded that, " ........... both the Main Mullaperiyar dam and Baby Dam are likely to undergo damage which may lead to failure under static plus earthquake condition and therefore needs serious attention .... ".

182. Kerala submits that the dam suffered heavy lime loss between 1930 and 1960 forcing Tamil Nadu to grout admittedly 542 MT of cement in this period.

183. On the aspect of impact of structural degeneration, Kerala's submission is that Mullaperiyar dam is a composite gravity dam constructed of lime surkhi mortar and lime surkhi concrete; that inner core of the dam, which constitutes 62% of the total volume, admittedly consists of lime surkhi concrete; and that Mullaperiyar dam has suffered heavy leaching of lime and has lost as much as 30.48 MT per year as found by the Expert Committee of Tamil Nadu, which has been admitted by PW-1. Kerala has highlighted that the density of the materials used in the dam has gradually gone down from 150 lbs/cft considered in 1895 to 135 lbs/cft in 1986 and that such gradual reduction testifies structural degradation of the Mullaperiyar dam.

184. As noted earlier, when the matter was initially taken up by the Constitution Bench it was felt that all the aspects of the matter including safety of Mullaperiyar dam need to be examined by an Empowered Committee (EC), which may help the Court in deciding the matter effectively. Accordingly, on 18.2.201 O the Constitution Bench directed the Central Government to constitute an EC under the Chairmanship of Dr. A.S. Anand, former Chief Justice of India, and comprising of . two members nominated by the States of Kerala and Tamil Nadu and two renowned technical experts. Kerala nominated Justice K.T. Thomas, a former Judge of this Court, and Tamil Nadu nominated Justice (Dr.) A.R. Lakshmanan, a former Judge of this Court, to the EC. Two renowned technical experts, Dr. C.D. Thatte and Shri D.K. Mehta were nominated in consultation with the Chairman of the EC. As per the terms of

reference, the EC was free to receive further evidence as it considered appropriate. The two experts, Dr. C.D. Thatte and Shri D.K. Mehta have long experience in all facets of water

sector. EC got investigations, tests and technical studies carried out through the three apex organizations, besides other

specialized organizations of the Government of India and, especially, expert agencies with a view to appreciate the diverse stand of the two States. In all, 12 investigations and technical studies, besides some site studies, were directed to be carried out to assist the EC to appreciate the stand of the two States and for submission of its report to this Court. The EC also visited Mullaperiyar dam (main dam), Baby dam and earthen bund from the Periyar lakeside as well as from the

downstream side. Before EC, the representative of both States explained theories of the existing dam. The two technical

members made a visit to drainage galleries and spillway for better appraisal of the dam site. The two e~perts again visited the dam site for site appraisal and submitted their report.

185. The reports and investigations, tests and studies (ITS reports) are contained in 50 CDs and 4 DVDs. The report of

EC consists of 8 Chapters. Chapter I has the title "Dams - An Overview". Chapter II deals with three aspects, viz., (a) Use of Periyar waters; (b) Evolution of Periyar Project; and (c)

Mullaperiyar dam Dispute in the Supreme Court. Chapter Ill refers to the issues settled by the EC. Chapter IV contains -

(i) Report of visit of the EC to Mullaperiyar dam site/areas during 19-22.12.2010; (ii) Resolutions of the EC dated 21.12.2010, 7.1.2011 and 5.12.2011; and (iii) Report of visit

by two technical members (Dr. C.D. Thatte and Shri D.K. Mehta) during 22-26.12.2011. Chapter V records responses

in brief of the parties to the issues framed by EC. Chapter VI is appraisal and analysis of the reports of technical investigations, tests and studies. Chapter Vil records

conclusions. Chapter VIII deals with general observation with the title, "Way Forward-Towards An Amicable Resolution". Two notes, one from Justice K.T. Thomas, member of the EC, and the other from Justice (Dr.) A.R. Lakshmanan, member of the EC, on Chapter VIII of the report of the EC are also appended to the report.

186. In Chapter Ill, the EC has recorded the issues for consideration. One of the issues, viz., Issue No.4 for consideration reads, "Should the reservoir level be raised from 136 ft.? If yes, what further measures for strengthening the existing dam, do the two parties envisage, to allow the raising of reservoir level from 136 ft. to 142 ft. and beyond?"

187. In Chapter V, the EC has noted responses by Tamil Nadu and Kerala to the issues framed by it.

188. Chapter VI, in which appraisal and analysis of ITS reports have been made, shows that following tests and studies were formulated so as to effectively deal with the concerns and grievances of the two States:

"A. HYDROLOGIC SAFETY

Title Purpose of ITS 1. Verification of the To determine:

.

Probable Maximum Flood (PMF) computations with (i) Probable Maximum flood routing for revisiting Flood (PMF) spillway capacity.

(ii) Outflow PMF hydrograph and its moderation from Mulla Periyar Dam upto tip of ldukki reservoir.

(iii) Outflow PMF hydrograph of ldukki reservoir.

(iv) Maximum Water Level (MWL) for various

scenarios of operative I To deter inoperative

gates for different FRLs.

(v) Free board 2. Integrated Dam Break. To assess Dam Break

Flood study from Mulla Flood that may be Periyar Dam to ldduki caused by different Dam and beyond to modes of failure/cascade

enable preparati'on of an effect in case of c

Emergency Action Plan. occurrence of MPD Preparation of a sample break. To identify the of likely inundation map plausible worst case of Dam Break Flood going down Periyar river from

MPD to ldukki reservoir

tip (in 1st phase) and beyond (in other 2 phases). To determine maximum inundation on

both banks for

preparation of Emergency Action Plan under Disaster

Management Plan. 3. Back-water studies To determine afflux

upstream of tip of Mulla (swelling) above the Periyar Reservoir into MWL in the upstream main stem and tributaries. from tip of the reservoir

caused due to infiow 4. Contour map of reservoir congestion.

area from present water level to 165 ft (50.29 m)

elevation.

[R.M. LODHA, CJI.] 5. Computerized Reservoir To determine loss of

Sedimentation Survey for storage due

assessment of present sedimentation and its . elevation-area-capacity effect (if any) on

relations. Assessment in Proba.ble Maximum higher elevations by Flood attenuation.

Remote Sensing.

Note: Side items of ITS pertain to i) Dams built with spillway design flood less than PMF, ii) Availability of water for Tamil Nadu, and iii) Requirement for environmental flow.

B. STRUCTURAL SAFETY 6. Mapping of upstream To scan upstream

face of dam above water face of Dam for level by means of discontinuities, cracks, photography hollows, voids & joints etc. above water level by grid based

photography.

7. Underwater scanning of To scan upstream

upstream face of the dam face of Dam for by means of a Remotely discontinuities, cracks, Operated Vehicle to hollows, voids &j oints assess its condition. etc. under water by means of a Remote

Operated Vehicle.

8. Studies of seepage and (i) To compile measured

its free lime content. values of seepage from dam body and foundation.

(ii) To determine proportion

of seepage through dam body/

foundation by flow net studies.

(iii) To determine leached free lime content in seepage.

9. Determination of in-situ/ To carry out core drilling ex-situ strength & in Dam body/ foundation

integrity of the dam body to enable following materials and foundation physical and chemical,

for using in safety/ in-situ and ex-situ (in stability status laboratories) tests. assessment.

In-situ Tests:

(i) Sonic test

(ii) Gamma - Gamma I Neutron-Neutron

(iii) Dye Tracer

(iv) Electrical Resistivity &

Geophysical Tomographic Study Ex-situ Tests:

(i) Compressive strength

(ii) Tensile Strength

(iii) Modulus of Elasticity (Static as well as

dynamic)

(iv) Poisson's ratio

(v) Density

(vi) Free Lime

(vii) Chemical analysis of

materials

[R.M. LODHA, CJI.] easurement o oss o To determine loss of stress in the sample pre pre-stress and hence sfressed cable residual pre-stress in the cable anchors installed in 1981, as part of

strengthening measures. Note: Side items of ITS pertain to i) Thermal properties of backing concrete and effect on interface, ii) Instrumentation, and iii) Stability of Main and Baby Dam.

C. SEISMIC SAFETY 11. Finite Element Method To determine tensile

(FEM) analysis stress caused due to employing (response Earthquake forces spectra) I (time histories) based on:

to asses stability of dam 20 under design basis/ (i) FEM Studies maximum credible based on Response earthquake forces. Spectra method (in two parts) submitted by SoK.

(ii) 30 FEM studies (two times) submitted by So TN.

(iii) 20 FEM studies (in two parts) based on Time

History analysis. 12. Identify 'evidence of To make a traverse and

geological fault in the identify evidence if any, surroundings of the of the · suspected Baby Dam. geological fault in the

Baby dam foundation. Note: Side items of ITS pertain to i) Study of 3D FEM Analysis

by Prof. R.N. Iyengar of Indian Institute of Sciences, Bangalore,

ii) Seismic Design Parameters of Mulla Periyar Dam, and iii) Impact of recent earthquake events."

189. The above reports have then been carefully analysed and on the basis of the appraisal of the ITS reports, EC held that Probable Maximum Precipitation (PMP) considered earlier was correct and the determination of observed maximum flood in 1943 was not.reliable. EC's assessment is that peak of PMF

reaching the Mullaperiyar dam reservoir I periphery I upstream tip remains at 2.12 lakh cusecs (6003 cumecs).

190. EC has been of the view that spillway designed capacity of Mullaperiyar dam for flood lower than PMF is

acceptable. The EC carefully analysed the two studies, viz., (i)

· study above water level by photography, and (ii) study below

water level by means of a Remote Operated Vehicle, upto a safely reachable level, and on appraisal from both scans/ studies read together did not apprehend cause for concern about manifestation of any distress for the dam.

191. EC has also carefully considered the concerns expressed by Kerala with regard to (a) seepage measurement and assessment of loss of free lime; (b) loss of strength of dam body constituents due to lime loss; and (c) vulnerability due to

free lime loss. According to EC appraisal, the total lime leaching in ·116 years of dam's existence was about 3.66%,

which is less than the upper permissible limit of 15-20%. EC held that as lime loss as assessed was far within permissible limits, there is no cause for concern about loss of strength of Mullaperiyar dam.

192. The physical properties of dam body material has also been reviewed and assessed by applying in situ non destructive tests, viz., (a) sonic test from dam's upstream face;

(b) neutron-logging and tracer study; (c) geophysical tomographic study; and (d) scanning of internal surface of bore

[R.M. LODHA, CJI.] hole walls using digital video recording system. EC also requested Tamil Nadu to obtain and test core samples from dam body I foundation rock, besides carrying out in situ tests in 9 holes on Mullaperiyar dam, of 150 mm size and more, which were got done by Tamil Nadu. These test reports were also considered. The chemical tests on constructed material used in the dam body and reservoir water were also conducted. The test results indicate innocuous nature of all these materials.

193. All time seepage data of Mullaperiyar dam has been appraised and analysed by EC, which indicates that it is within permissible limits. Testing of one ungrouted cable anchor for residual pre-stress was got done. Analysis has also been done . of thermal properties of backing concrete and effect on interface. The detailed appraisal and analysis of ITS reports for seismic design parameters on Mullaperiyar dam show the recent earthquake events to be transient and inconsequential.

194. One of the apprehensions highlighted by Kerala is that a dam break flood would cause large scale devastation. This aspect has been considered by the EC under the head "Dam Break Flood and possible cascading effect". EC in this regard has observed that Kerala has not supplied to it inundation maps even for normal flood with return periods such as 50, 100 years in downstream area for phase-I and between ldukki and lower Periyar dam or further downstream for later phases. Such inundation maps have to be prepared for Emergency Action Plan. Kerala also has not submitted any assessment as prescribed in CWC 'Guidelines for Development and Implementation of Emergency Action Plan for Dams, May, 2006'. EC, accordingly, depended on maps developed by using Archived Satellite Imagery and Survey of India toposheets, through 'Mapsets', and accomplished illustrative contouring of area between Mullaperiyar dam and ldukki complex. EC has observed that all the projections I concerns by Kerala were not based on computations I studies. Despite the request made to Kerala to supply contour map, Kerala did not do so. EC has

further observed that Kerala's projection is conjectural since there is deficiency in assessing the likely inundated area. EC, therefore, did not accept the scare of dam break flood.

195. Having done elaborate and detailed appraisal and

analysis of the voluminous tests and reports of experts and having regard to the concerns expressed by Kerala about the safety of the Mullaperiyar dam, EC has summarized its conclusions on the three aspects, viz., (a) hydrologic safety; (b) structural safety; and (c) seismic safety as follows:

"A) Hydrologic Safety 23. The MPD is found hydrologically safe. The Probable Maximum Flood (PMF), with a peak flow of 2.12 lakh cusecs (6003 cumecs) is accepted by EC. It can be routed over the reservoir FRL 142 ft (43.28 m) to safely pass over the MPD spillway with 13 gates operative, resulting into a peak out flow of 1,43, 143 cusecs (4053 cumecs), raising the Maximum Water Level (MWL) to elevation 153.47 ft (46.78 m) transiently. Even for the Test Case of one gate remaining inoperative, the MWL raises to elevation 154.10 ft (46.97 m) when PMF impinges the reservoir at FRL 142 ft (42.28 m).

B) Structural Safety 24. Both the main and Baby Dam (gravity and earth), are structurally safe. FRL can be restored to the pre-1979 position. Following maintenance and repair measures, should however be carried out in a time-bound manner: i) treatment of upstream surface, ii) reaming of drainage holes, iii) instrumentation, iv) periodical monitoring, analysis and leading away the seepage from toe of the dam towards downstream, v) geodetic re-affirmation, etc.,

vi) the dam body should be grouted with a properly designed grout mix of fine cement I suitable chemical I epoxy I polymer according to expert advice so that its safety continues to remain present.

C) Seismic Safety 25. MPD is found .to be seismically safe for FRL 152 ft · (46.33 m) I MWL 155 ft (47.24 m) fodhe identified seismic design parameters with acceleration time histories under 2-D FEM Analysis. The strength and other properties of dam material presently available, indicate ample reserve against the likely stresses I impacts assessed under this analysis. In addition, reserve strength of cable anchors makes the dam further safe. The suspicion about existence of a geological fault in the Baby Dam foundation is ruled out. The recent earthquake activity in the dam area is considered of no consequence to the seismic safety. Also, it has caused no distress to MPD / ldukki dams."

196. Kerala has vehemently challenged tt)e EG report and its conclusions. Mr. Harish Salve, learned senior counsel for Kerala, argues that the ITS reports contained in 50 CDs and 4 DVDs are not admissible and should not be considered as part of material on record before this Court. He submits that EC suo motu decided to conduct investigations, tests and studies on various aspects related to the case through the apex organizations, the Coordination Committee was formed, headed by Dr. C.D. Thatte, member of the EC, and consisting of representatives of Kerala and Tamil Nadu and though the .representatives of States were made part of the Coordination Committee. but their role was limited to more of being an observer and unilateral decisions regarding the studies, etc., were taken by Dr. C.D. Thatte, which were prejudicial to the interest of Kerala. Kerala's grievance is that the EC on 5.12.2011 declined to disclose and supply the copies of results and ITS reports without dealing with the question of prejudice. Subsequently, EC submitted its report before this Court and the Court directed the Registry on 4.5.2012 to supply copy of the report of the EC to party States and, accordingly, the Registry

..

of this Court made available a photocopy of the report. The

report supplied by the Registry to Kerala did not include the results and reports of the ITS listed in Annexure 6.1 of the report but later on pursuant to the order of this Court dated 31.8.2012, all 50 CDs and 4 DVDs were supplied to the counsel for Kerala. It is submitted on behalf of Kerala thafthe fair procedure and rules of natural justice demanded that the EC should have disclosed the results and reports of ITS relied upon by it and given an opportunity to Kerala on the acceptability of the ITS reports. It is strenuously urged by learned senior counsel for

Kerala that the ITS reports are the opinions of experts and, therefore, the EC could not have relied upon such results and

reports without giving an opportunity to it to meet the adverse contents and Kerala has the right to cross-examine the authors and also to lead evidence of experts, if any, challenging the

adverse results and reports of the ITS. In this regard, Kerala referred to the application made before EC on 21.11.2011.

Kerala also reli13d upon the decision of Queens Bench in Regina⁷⁵ .

197. We are not persuaded by the submissions of Mr. Harish Salve. It is true that 50 CDs and 4 DVDs containing ITS

reports were supplied to Kerala pursuant to the order of this Court dated 31.8.2012 after the report had been submitted by the EC but the fact of the matter is that the EC decided to

conduct the investigations, tests and studies on various aspects relating to the safety of the Mullaperiyar dam through the apex

organizations pursuant to the task given to it by this Court. The EC in its proceedings dated 17.2.2011 formed a Coordination Committee which comprised the representatives of both the

States. It is very difficult to accept that the role. of the . representatives of the States in the Coordination Committee

was limited to that of being an observer. The ITS reports have been given by the organizations and bodies which are expert on the job. We have no hesitation in holding that the

[R.M. LODHA, CJI.) investigations, tests and technical studies were directed to ·be carried out by the EC in association with representatives of both the States.

198. Moreover, this Court appointed EC to assure itself about the safety of the Mullaperiyar dam. The EC, we must say, has completed its task admirably by thoroughly going into each and every aspect of the safety of Mullaperiyar dam. We do not find any merit in the objections of Kerala challenging the findings and conclusions of the EC on hydrologi¥ safety, structural safety and seismic safety of the dam. The findings of EC with elaborate analysis of reports of investigations, tests and studies lead to.·one and only one conclusion that there is no change in the circumstances necessitating departure from the earlier finding on the safety of Mullaperiyar dam given by this Court in 2006 judgment. As a matter of fact, there is no change in circumstances at all much less any drastic change in circumstances or emergent situation justifying the reopening of safety aspect of Mullaperiyar dam which· has been determined by this Court. in the earlier judgment.

Findings on Issue Nos. 2(a), 3, 4(a), 4(b) and 10

199. In light of the above discussion, our findings on Issue Nos. 2(a), 3, 4(a), 4(b) and 10 are as follows:

(i.) Kerala Irrigation and Water Conservation (Amendment) Act, 2006 is unconstitutional and ultra vires in its application to and effect on the Mullaperiyar dam.

(ii.) The rights of Tamil Nadu, crystallized in the judgment dated 27.2.2006 passed by this Court in W.P. (C) No.386/2001 cannot be nullified by a legislation made by the Kerala State legislature.

(iii.) The earlier judgment of this Court given on 27.2.2006 operates res judicata on the issue of a~ the safety of Mullaperiyar dam for raising water level to 142 ft. and ultimately to 152 ft. after completion of further strengthening measures on the Mullaperiyar dam.

(iv.) The plea raised by Kerala relating to the lease deed dated 29.10.1886 and structural safety of Mullaperiyar dam have been finally decided by the judgment of this Court dated 27.2.2006 and Kerala is estopped from raising or re-agitating these issues in the present suit.

Kerala cannot obstruct Tamil Nadu from increasing the water level of Mullaperiyar dam to 142 ft. and from carrying out repair works as per judgment dated 27.2.2006.

200. This issue covers the controversy as to whether Kerala is estopped from contending that Periyar river is not an

inter-State river.

201. Tamil Nadu in the plaint has averred as follows: "The plaintiff, defendant no.1, State of Kerala are the two riparian States through which the Inter-State river Periyar flows. The river is one of the west flowing rivers in the State of Kerala, with a portion of its catchment lying with the State of Tamil Nadu ............. "

202. Traversing the above pleading of the Tamil Nadu, Kerala has set up the case that river Periyar is not an inter state river but it is intra-State river; that it rises in Quilon District in Kerala and traverses only through the territory of Kerala before falling into the Arabian sea.

203. In its replication, Tamil Nadu has averred that, in any event, in the earlier proceedings, Kerala had raised the plea of lack of jurisdiction of this Court to entertain the river water disputes with reference to Article 262 of the Constitution read with Section 11 of the Inter-State River Water Disputes Act, 1956. This plea was raised on the ground that river Periyar is an inter-State river. Tamil Nadu, thus, has set up the plea that Kerala is estopped from raising a plea that river Periyar is not an inter-State river.

204. Mr. Harish Salve, learned senior counsel for Kerala, argues that river Periyar rises in Kerala and flows for a length of 244 km. in Kerala before entering in the sea at Kerala coast. River Periyar does not touch any part of Tamil Nadu. He submits that in the earlier proceedings, Kerala had not admitted that river Periyar was an inter-State river. Learned senior counsel contends that river Periyar is an intra-State river. and Kerala's averments in the earlier proceedings does not estop it from raising the plea that river Periyar is not an inter state river.

205. In 2006 judgment, one of the points considered and decided by this court is whether the jurisdiction of this court is barred in view of Article 262 of the Constitution read with Section 11 of the Inter-State River Water Disputes Act, 1956. This point would not have been raised by Kerala but for the fact that river Periyar happened to be an inter-State river. While deciding this point, obviously, the court proceeded on the footing that river Periyar is an inter-State river. This court decided this point against Kerala. It appears that in the review petition, for the first time, Kerala took the specific plea that Periyar is an intra-State river but covered by an inter-State agreement. The review petition has been rejected by this Court on 27.7.2006.

206. It is true that in the earlier proceedings there is no express and categorical admission of Kerala that river Periyar is an inter-State river, but the very plea of lack of jurisdiction of this court for considering the applicability of Article 262, as noted above, would not have been raised by Kerala if river Periyar was an intra-State river. Moreover, the entire area

drained by the river and its tributaries is called the river basin. It is well-understood in the water laws that the basin of any river includes the river valley. The topographical map of Periyar river

basin shows that part of Periyar basin (about 114 sq. km.) is in Tamil Nadu. This is established from Water Atlas of Kerala

published by Centre for Water Resources Development and Management, Kazhikode, Kerala. Though the Periyar basin area that falls in Tamil Nadu is very small but, in our view, that does not make any difference insofar as the status of Periyar river as inter-State river is concerned. The fact of the matter is that 114 sq. km. of Periyar basin area falls in Tamil Nadu. This is also fortified by the advance report of Public Works Department, Government of Kerala, which, inter alia, states,

"the rivers which have their drainage area lying in more than one State have been brought under the category of Inter-State

rivers and a consolidated study has been admitted in this

chapter .............. ." "Of the west flowing rivers, those which ·have a portion of their catchment area lying in Madras State

are .............. (iv) Periyar."

207. Kerala's witness M.K. Parameswaran Nair has admitted that in Chapter LXlll under the heading "Interstate waters" from "Water Resources of Kerala" published by Public Works Department, Government of Kerala in 1958, Periyar has

been mentioned as an inter-State river. This witness also admits that Water Atlas of Kerala wherein details of Periyar

basin are given shows that part of the basin falls in the neighbouring State of Tamil Nadu.

208. Since Kerala has r;iised the plea that river Periyar is an intra-State river, obviously, burden is on Kerala to prove this

fact. Kerala, except asserting that Periyar river rises in and traverses only in the territory of Kerala before entering into Arabian sea and no part of the land in Tamil Nadu abuts river

Periyar, has not produced substantial evidence to prove that river Periyar is an intra-State river. Kerala has not discharged

its burden to the satisfaction of the Court.

209. It is true that averment of Tamil Nadu in the plaint that the two States - Kerala and Tamil Nadu .-. are riparian States is not right in its entirety because Tamil Nadu is not a riparian State but the status of Periyar river as inter-State river, on the basis of what we have observed above, cannot be overlooked. It is not open to Kerala to take a totally inconsistent plea and begin fresh controversy about the status of Periyar river on the ground that the earlier plea was founded on some erroneous premise. In our view, Kerala cannot be permitted to contend that Periyar river is not an inter-State river.

Finding on Issue No.8

210. In light- of the above discussion, it is held that Kerala cannot be permitted to contend that river Periyar is an intra state river. Issue No.8 is answered accordingly.

Issue No.9

211. This issue is founded on the offer made by Kerala to Tamil Nadu to construct a new dam across river Periyar in the downstream region of Mullaperiyar dam. EC in Chapter VIII under the titie "Way Forward - Towards An Amicable Resolution" has dealt with this aspect as a first alternative and suggested as follows:

"1. That the SoK may construct a new dam, at its own expense to serve its own perceptions, if technoeconomically cleared by the Planning Commission, and cleared by MoEF in accordance of their regulations. The construction of a new dam, giving due margin for inflation etc, may cost the exchequer more than Rupees one · thousand crores. The statutory clearances, fixing of a construction agency, preliminary works, the actual construction and decommissioning with demolition of existing dam is likely to take 8 to 10 years. The existing dam shall not be dismantled, demolished or

decommissioned till the new dam construction is completed and it becomes operational. Till such time, the rights of the So TN in the existing Dam to all waters of Mulla Periyar Dam arising out of the Lease Deed of 1886 and the Agreements of 1970, shall be fully honoured.

2. However, the operation of the New Dam would commence only after:

2(a) A fresh MOU is executed between the SoK and the

So TN.

2(b) That to control, manage, operate, maintain and

regulate the waters of the New Dam, an Independent Committee I Board, to be chaired by a representative of the Union of India, with representatives of the SoK and the SoTN as its

Members, is put in place;

2(c) That the terms of rent/levies etc payable by the

SoTN to the SoK are settled and the power generation rights of the two States are settled

beforehand;

2(d) That before construction of the new dam and till its

commissioning, the existing dam will be. strengthened by the measures suggested by the CWC, including Dam Safety requirements as

already voiced, which still remain to be carried out. 2(e) That the So TN will be entitled to all its existing rights

including all waterlevels under the Lease Deed of

1886 and Agreement of 1970.

2(f) That decommissioning or demolition of the existing

dam would be subject to the conditions 2(a) to 2(e)

being met by the two Party States.

2(g) The Empowered Committee had made the

suggestion to the two States during the hearing on 2nd January, 2012. Learned counsel for the parties had sought time to consult the States and file their responses. Counsel for the parties later on gave their responses ingeneral terms, but there has been no direct response or opposition to the alternatives suggested." ·

212. Any amicable resolution of the present dispute between the two States would have been really good for the people of these States but this has not been possible as the two States have sharp conflict over the subject matter and their stance is rigid, inflexible and hard. The offer made by Kerala for construction of new dam has been outrightly rejected by Tamil Nadu. It is important to bear in mind that Mullaperiyar dam has been consistently found to be safe, first, by the Expert Committee, and, then, by this Court in 2006 judgment. The hydrological, structural and seismic safety of the Mullaperiyar dam has been confirmed by the EC as well.

Finding on Issue No.9

213. In this view of the matter for the construction of new dam, there has to be agreement of-both the parties. The offer made by Kerala cannot be thrusted upon Tamil Nadu. Issue No.9, therefore, has to be decided against Kerala and it is so held.

214. EC has also suggested the following second alternative:

"2. The Dam Safety Organization Central Water Commission, the Government of India (Ministry of Water Resources), has laid down the Criteria and Guidelines for Evacuating Storage Reservoirs, Sizing Low Level Outlets and Initial Filling of Reservoirs.

i) According to the criteria, generally speaking, Dams should be provided with low level outlets of adequate capacity to lower the reservoir water level to a specified elevation for inspection, maintenance and repair, and ii) to control the rate of reservoir

pool rise during initial filling.

ii) The Guidelines recommend that an outlet should be

provided at the lowest possible level and should be of sufficient dimensions to cater to evacuation of storage with requisite flow capacity. The decision about level at which the outlet has to be provided is left to the concerned dam owning entity. The level will depend upon assessment of the dam's condition, a judgment on location at which distress may be caused, its nature and the time of evacuation needed for enabling completion of

restoration measures.

3. In the existing MPD project, as noted in Chapter-ll(b) (supra), a tunnel had been designed with a 0-Section 12 feet wide and 7.5 ft high with provision of the sluice head gate having sill at El 106.5 ft for diversion of water from Periyar reservoir to Vaigai basin in the So TN. This tunnel

1958. was modernized by widening and lining in the year The tunnel can allow reservoir draw-down to 106.5 ft as per criteria laid down in (i). Storage lower than El 106.5 ft to an identified elevation based on assessment of likely distress cannot be drawn-down through the present arrangement of drawl of water for the So TN through the existing tunnel.

4. Further, digging of a New Tunnel at say at EL 50 ft., of course, after conducting surveys, designs, and techno economic feasibility studies, with requisite sluice gates for evacuation of reservoir water from EL 106.5 ft to say 50 ft. These studies will have to be undertaken within a specified time frame. It goes without saying that the water flow from the New Tunnel can be used for power generation or for any other purpose by making changes in its existing infrastructure. Depending upon a decision

about the elevation of the New Tunnel outlet, evacuation

of the MPD reservoir will be possible in corresponding

time period.

The new tunnel, will need to be constructed by the SoTN, since the ownership of the existing dam vests in it. The total expenditure for construction of the new tunnel should be borne by the So TN. The costs may be small as compared to the cost of the replacement of the new dam. The SoTN should accomplish surveys and feasibility studies for the c proposal of having a new tunnel within a year.

The New Tunnel say at El 50 ft will enable the So TN to use additional water available in storage between EL 106 ft to 50 ft. At present, these waters are remaining unused.

More importantly, if this alternative is implemented in an agreed period of time, the fear perception in the minds of people of the SoK will be set at rest. They can then appreciate that the New Tunnel is going to help evacuation of storage faster and better, in case the dam develops any distress. As a gravity dam seldom gives in suddenly, such evacuation will reduce Dam Break flood (DBF) magnitude significantly.

Though, the demand of the SoK for 1.1 TMC of water for Environmental Flow is not substantiated, yet, a legitimate need which is yet to be assessed, can be met with after the FRL is raised to 142 ft. A small pipe outlet of a suitable diameter through right bank hillock can be dug to release the Environmental Flow as firmed up by the SoTN in

ewe consultation with & the SoK.

5. That a MoU would have to be executed by the SoTN and the SoK, in the presence of a representative of the Govt.

of India, Ministry of Water Resources, regarding the construction of the new tunnel within a specified time."

215. EC has itself noted that the second alternative is dependent on agreement between the two States but to us there appears to be no possibility of mutual agreement on this aspect as well. The alternatives suggested by EC are worth exploring by the two States but having regard to the unbending stance adopted by them, this does not seem to be possible.

We, however, grant liberty to the parties to apply to the Court if they are able to arrive at some amicable solution on either of

the two alternatives suggested by the EC.

Issue Nos. 2(b) and 11 216. With reference to these issues, it is strenuously urged by Kerala that Tamil Nadu has not suffered any injury because of the reduction of the storage at Mullaperiyar dam to 136 ft. since 1979. According to Kerala, more water was drawn and

more area was irrigated after 1979. Kerala has in this regard relied upon the data supplied by Tamil Nadu Public Works

Department and the analysis thereof. It is submitted that average water drawn during the pre-1979 period was 19,277 Mcft. while in the post-1979 period the water drawn was 21,434 Mcf. As regards extent of irrigation, Kerala submits that the

extent of irrigation in Tamil Nadu from Mullaperiyar, water has admittedly increased from about 1, 71,307 acres before 1979

to 2,31,412 acres. Kerala has also relied upon the answers of PW-1 to question Nos. 585 to 601 and 58 to 59. Kerala has also relied upon the decision of this Court in State of Andhra

Pradesh3 wherein this Court observed," ....... that in a suit for injunction filed by one State against the other State, the burden

on the complaining State is much greater than that generally required to be borne by one seeking an injunction in a suit between private parties. The complaining State has to establish that threatened invasion of rights is substantial and of a serious

[R.M. LODHA, CJI.] magnitude. In the matter between States, injunction would not follow because there is infraction of some rights of the complaining State but a case of high equity must be made out that moves the conscience of the Court in granting injunction ......."

217. Tamil Nadu on the other hand asserts that raising the water level in the dam to original FRL is absolutely necessary to irrigate the lands in about 2 lakh acres in five drought-prone districts of Theni, Dindigul, Madurai, Sivagangai and Ramanathanpuram. About 6.8 lakh farmers and agricultural labourers besides 80 lakh people of the above five districts continue to suffer due to inadequate timely supply of water for irrigation and drinking purposes.

218. Pertinently, EC has also considered this aspect and observed as follows:

"EC has assessed that increase in irrigation in Vaigai Basin is mainly due to i) construction of Vaigai Dam in 1954 and related canal distribution system post 1974, which worked as a balancing reservoir for release from · power station in non-irrigation months from 1954 onwards, and ii) World Bank assisted Modernization of Periyar Vaigai Irrigation Project, phase-I & II, implemented in 1980's, which enabled improved Water Use Efficiency. Although firming up of irrigation is achieved by.the So TN, there is still large drought-prone area in Vaigai Basin and adjoining area, which needs protective irrigation. Also domestic I municipal I industrial needs of the area are significant. These present requirements remain unmet, if FRL is not restored even partially.

EC is unable to accept the submission of the SoK that no harm will be done under these circumstances to the So TN if FRL is not restored."

219. Insofar as drawal of water in pre-1979 period and post-1979 period is concerned, the sole witness of Tamil Nadu has admitted that in the post-1979 period the water drawn was 21,434 Mcft. and the average water drawn pre-1979 period

was 19,277 Mcft. Similarly, he has admitted increase of irrigation from 1,71,307 acres before 1979 to 2,31,412 acres

in 1992-93, but, as observed by EC, this has been due to construction of Vaigai dam in 1954 and related canal distribution system post-1974. The five districts Theni, Dindigul, Madurai, Sivagangai and Ramanathanpuram that are served by Periyar project are drought prone. About 2 lakh acres of land fall in these five districts which needs to be irrigated .. The inadequate timely water supply of water for irrigation and drinking purposes to the population of these districts may affect their lives as well as livelihood. The increase of irrigation and

more drawal of water post 1979 still appears to be deficient for the population of more than 80 lakh people in these districts.

220. In these facts, therefore, it can safely be said that Tamil Nadu has been able to establish that invasion on its rights is

substantial. Tamil Nadu has been able to make out a case for grant of injunction on the principles laid down by this Court in

State of Andhra Pradesh3. Moreover, present suit is not a suit for injunction simpliciter as the main prayer is that Kerala Irrigation and Water Conservation (Amendment) Act, 2006 be

declared unconstitutional and ultra vires in its application to and effect on the Mullaperiyar dam.

Findings on Issue Nos. 2(b) and 11 221. In view of the foregoing discussion, we hold that Tamil

Nadu is entitled to the reliefs as prayed in para 40 (i) and (ii) of the suit. Consequently, it is declared that the Kerala Irrigation

and Water Conservation (Amendment) Act, 2006 passed by the Kerala legislature is unconstitutional in its application to and effect on the Mullaperiyar dam. The 1st defendant - State of

Kerala - is restrained by a decree of permanent injunction from applying and enforcing the impugned legislation or in any

[R.M. LODHA, CJI.] manner interfering with or obstructing the State of Tamil Nadu from increasing the water level to 142 ft. and from carrying out the repair works as per the judgment of this Court dated 27.2.2006 in W.P.(C) No. 386/2001 with connected matters.

222. However, to allay the apprehensions of Kerala- though none exists - about the safety of the Mullaperiyar dam on restoration of the FRL to 142 ft., a 3-Member Supervisory Committee is constituted. The Committee shall have one representative from the Central Water Commission and one representative each from the two States - Tamil Nadu and Kerala. The representative of the Central Water Commission shall be the Chairman of the Committee. The Committee will select the place for its office, which shall be provided by Kerala. Tamil Nadu shall bear the entire expenditure of the Committee.

223. The powers and functions of the Supervisory Committee shall be as follows:

(i) The Committee shall supervise the restoration of FRL in the Mullaperiyar dam to the elevation of 142 ft.

(ii) The Committee shall inspect the dam periodically, more particularly, immediately before the monsoon and during the monsoon and keep close watch on its safety and recommend measures which are necessary. Such measures shall be carried out by Tamil Nadu.

(iii) The Committee shall be free to take appropriate steps and issue necessary directions to the two States - Tamil Nadu and Kerala - or any of them if so required for the safety of the Mullaperiyar dam in an emergent situation. Such directions shall be obeyed by all concerned.

(iv) The Committee shall permit Tamil Nadu to carry out further precautionary measures that may become necessary upon its periodic inspection of the dam in accordance with the guidelines of the Central Water Commission and Dam Safety Organisation. 224. The suit is decreed as above, with no order as to The following Order of the Court was delivered ORDER

In view of our separate judgment pronounced today in Original Suit No.3 of 2006 (State of Tamil Nadu v. State of Kerala and another), nothing further remains to be decided in this special leave petition and it is dismissed accordingly.