OPINION OF THE COURT
Asch J.The project which is the subject of our scrutiny is not a modest one-family cottage standing alone in the middle of an unpopulated prairie. The approval by the Board of Estimate was for a massive private development to be built in the center of one of the most congested neighborhoods in Manhattan.
As approved, the project includes twin 44-story towers, proposed construction of 520 luxurious apartments, a 250-room hotel, a shopping mall, office space, two health clubs, a community facility and almost 500 parking spaces. An undertaking of such leviathan proportions must have substantial environmental impact. It was precisely because of the possibility of long-term or cumulative adverse effect that SEQRA (New York State Environmental Quality Review Act [ECL 8-0101 et seq.]) was enacted.
*458On appeal, petitioners raise various challenges to the Board of Estimate determination relating to the outdoor space provided, mitigation variables and various purported adverse environmental impacts arising from the increased use and population on the lot. Most of these factors were adequately addressed by the final environmental impact statement (FEIS) and we find no meaningful basis on which to disturb the administrative determination as to them.
However, with respect to respondents’ treatment of one variable, i.e., sewage, there remains a serious issue as to adverse environmental impact, and the manner and the time in which the FEIS was amended to change respondents’ notice as to which sewage treatment plant would be utilized.
The developer and various city officials met in March 1985 to prepare various issues in the draft environmental impact statement (DEIS). It was completed on July 1, 1988. Among the infrastructure factors were included drainage, sewage, and waste disposal. A public hearing on the DEIS was held on October 5, 1988. The FEIS was completed on November 4, 1988, and included the comments on the DEIS and responses thereto. The FEIS included discussions on drainage, sewage, and waste disposal. Prior to, and subsequent to, issuance of the FEIS, the project was altered and downscaled in accordance with many of these comments. Most of these issues are not relevant for this appeal. On December 15, 1988, the developer informed the city that the FEIS was incorrect as to the sewage treatment facility which would be utilized. The FEIS had specified that sewage would be directed to the Ward’s Island Water Pollution Control Plant. However, the actual destination of sewage would be the Newtown Creek water pollution control plant. On January 9, 1989, the city issued a notice of correction, indicating such change, which was distributed to the Board of Estimate. This plan for disposing of sewage had not been known to those involved in the formulation of the DEIS or the FEIS. Neither did petitioners and others knowledgeable in sewage and waste disposal problems have notice of the change in plants. Three days later, on January 12, the Board of Estimate conducted a hearing at which the petitioners offered comments. Sewage was a topic of this discussion. After the hearing, the Board voted to adopt the resolutions which were relevant to this project.
Petitioners challenge the manner in which this notice of correction was issued, and argue that the principal agency and others who prepared the environmental impact state-*459merits did not have this information when they were formulated and that the Manhattan Borough President never received this information. Petitioners also argue that the change actually threatens a significant environmental impact.
There now exists a serious factual question of whether there will be a significant environmental impact in a practical sense under the new proposed plan for sewage disposal and whether those persons or agencies responsible under SEQRA, as well as the Board of Estimate, had an actual opportunity to study its impact.
The Ward’s Island treatment plant has a designed capacity of 290,000,000 gallons per day. The FEIS indicates that the project would produce 345,000 gallons per day. Newtown Creek has a designed capacity of 310,000,000 gallons per day. Respondents argue that whether the sewage goes to Ward’s or Newtown, it will constitute only a minimal portion of the daily sewage treated. While respondents note that the anticipated sewage is .092% of Ward’s actual capacity and only .079% of Newtown’s actual capacity, they rely on actual capacity, which is far in excess of the designed capacity. In any event, there is another real difference between the two treatment plants. Ward’s Island, the originally designated plant, conducts secondary sewage treatment, while Newtown, the plant which will be utilized, does not provide secondary sewage treatment. Respondents point out that the major difference relates to the removal of "two” pollutants, biochemical oxygen demand (BOD) and total suspended solids (TSS). TSS consists of an effluent which is a thin sludge containing heavy metals among other pollutants, while BOD is a measure of the amount of oxygen used up in the water by the decomposition of the organic wastes in the effluent. Actually, then, several potential pollutants are involved. The practical result is that Ward’s removes at least 85% of BOD and TSS while Newtown removes at least 50%. Greater quantities of untreated sewage therefore will be dumped in the East River from the Newtown plant than from Ward’s plant.
The respondents and the dissent conclude that this result is de minimis. But, the various city officials, the expert consultants, the public, as well as the Board of Estimate should have been afforded the opportunity to study the environmental impact of releasing this additional amount of untreated sewage into the East River. In addition, under the terms of a State pollution discharge elimination system permit granted by the New York State Department of Environ*460mental Conservation, the city may be barred from making new sewer connections if the Newtown plant continues to operate on any level beyond its permitted capacity. Thus, an additional flow of 345,000 gallons a day cannot be considered de minimis. This seems to undermine any firm conclusion that sewage disposal at Newtown will, at all times, have no more than marginal impact.
Respondents contend that pursuant to a consent decree entered with the State Department of Environmental Conservation in June 1988, a timetable to expand the flow capacity of Newtown Creek has been established with all construction to be completed by December 31, 1996. Assuming the city complies with all the provisions and time limits set forth in the consent decree (which is dubious given the history of government delay and the present fiscal difficulty), it should be noted that Appendix B to the decree allows for a waiver of the interim effluent limitations and even a shutdown of the Newtown plant during construction activities. This does not vitiate our conclusion that all the interested parties should have been afforded an opportunity to study and comment on the proposed change before the Board of Estimate approved the project.
We do not make any determination as to the adequacy of the Newtown Creek proposal. However, in view of these various considerations, it seems imperative to submit the technical and practical issues involved in the disposal of sewage to the appropriate administrative agencies before the plan is passed upon by the entity currently having jurisdiction (i.e., the City Council).
The matter of sewage disposal in New York City today is a serious problem. As the respondents correctly note, the sewer system presents a jurisdictional nightmare discoverable only in ancient records. Several city agencies, as well as private entities such as Con Ed, have jurisdiction over different maps and records. The consultant for the firm which prepared the sanitary valuations in the DEIS and FEIS submitted an affidavit which explained how the initial FEIS specified the wrong treatment plant. The consultant averred that the firm visited and inspected maps with several city agencies and sources including the New York City Bureau of Sewers and Drainage. The consultant became aware of the nonuniform nature of the maps and conflicting data and found it difficult to ascertain which water pollution control plant would treat *461the sanitary sewage from the project. During late 1985, the consultants contacted technical personnel from the drainage division of the Department of Environmental Protection to identify the designated treatment plant. The consultant was informed that the Ward’s Island plant services most of the upper East Side of Manhattan and would receive sanitary waste from the project. It was not until a meeting of Community Board 6 on December 7, 1988, at which petitioners apparently were present, that a participant raised the question of sewage treatment facilities and indicated her belief that Newtown Creek would be the correct plant. Thereafter, the consultants visited the City Bureau of Sewers and other agencies, reviewed updated and newly created maps and confirmed only then that Newtown Creek would be utilized for the project sewage. The following week, December 15, 1988, DEP was notified of this error, and the consultants participated in the issuance of the notice of correction.
If the error had been corrected well before the meeting of the Board of Estimate, it might not even be a substantive issue on appeal. However, the timing of the notice of correction and the subsequent approval raises an issue. The Board of Estimate was a policy-making body. What was bypassed, therefore, was the administrative expertise and the opportunity for meaningful public input based upon the changed plans. The Board of Estimate, like other administrative agencies, had "considerable latitude evaluating environmental effects and choosing between alternative measures” (Akpan v Koch, 75 NY2d 561, 570). "Nevertheless, an agency, acting as a rational decision maker, must have conducted an investigation and reasonably exercised its discretion so as to make a reasoned elaboration as to the effect of a proposed action on a particular environmental concern (see, H.O.M.E.S. v New York State Urban Dev. Corp., 69 AD2d, at 231, supra). Thus, while a court is not free to substitute its judgment for that of the agency on substantive matters; the court must ensure that, in light of the circumstances of a particular case, the agency has given due consideration to pertinent environmental factors” (supra, at 571).
However, here, on January 9, 1989, two months after publication of the FEIS which reported that sewage would be treated at the Ward’s Island plant, and three days before the Board of Estimate vote, the city’s Department of City Planning and Department of Environmental Protection issued a purported "notice of correction” stating that project sewage *462would be treated at the Newtown Creek Water Pollution Control Plant.
It would appear that the belated "notice of correction” was not received by the Manhattan Borough President, who sits on the Board of Estimate. To the extent the "notice” was distributed to expert government agencies and members of the public, it was distributed much too late to permit meaningful review or comment on its contents. Last minute notice may be, realistically, the equivalent of no notice. In this case, no notice, or even late notice, may vitiate the mountains of documents, the input of technical experts, the viewpoint of local citizens and the benefits of intensive negotiation, which would perhaps insure the most appropriate handling of the sewage.
The Newtown Creek plant, in contrast to the Ward’s Island facility, does not provide secondary sewage treatment, which is the minimum treatment required by State and Federal water pollution control laws. Even at the present time it handles sewage flow in excess of its design and permitted capacity. The "notice of correction” omitted mention of these facts.
The respondents’ violation of SEQRA mandates nullification of Board of Estimate approvals for the project. Courts throughout New York State require strict, literal compliance with the requirements of SEQRA. Accordingly, courts have often invalidated government approvals granted in violation of SEQRA. (See, e.g., Matter of E.F.S. Ventures Corp. v Foster, 71 NY2d 359, 371; Matter of Save the Pine Bush v City of Albany, 70 NY2d 193, 206; Chinese Staff & Workers Assn. v City of New York, 68 NY2d 359, 369; Matter of Tri-County Taxpayers Assn. v Town Bd., 55 NY2d 41, 45-46.)
This case highlights the importance of judicial vigilance with regard to compliance with SEQRA. The statute establishes a fundamentally democratic process whereby through draft and final environmental impact studies, accurate and complete information is made available to citizens and agencies with expertise and concern.
Sophisticated developers and compliant officials have learned, however, to maneuver through the requirements of SEQRA and once the levels of review have been climbed, given the limited scope of judicial review, it becomes extremely difficult for the courts in appropriate cases to intervene to protect the public.
*463Despite the legislative intent that all environmental impacts be identified, investigated, disclosed and considered, the misleading environmental impact statements here precluded informed public or agency comment on sewage treatment plans. In this critical area the key environmental disclosure documents relied on by the Board of Estimate prevented, rather than safeguarded the attention and balancing required by law. This shortcoming deprived the decision makers of a reasoned, lawful basis on which to review the project.
Accordingly, the judgment of the Supreme Court, New York County (Irma Vidal Santaella, J.), entered April 25, 1990, which confirmed the determination of the respondent Board of Estimate of the City of New York, dated January 12, 1989, and dismissed the petition, should be reversed, on the law and facts, and the application for an order nullifying the Board of Estimate approval granted without costs or disbursements.