The authority empowered to modify the layout plan and the public interest served by the modification were central legal principles established in the judgment.

( 1 ) CIVIL Writ Petition No. 6666 of 1999 has been filed by BU- Block Residents Welfare Association and 18 other residents by way of Public Interest Litigation.

( 2 ) THERE is a plot measuring 2. 5 acres (approx.) located in BU/cu Block Pitampura, New Delhi (hereinafter referred to as the disputed plot, for short ). This plot has been allotted to respondent No. 8, namely, Akhil Bhartiya Samajodhan Samiti for purposes of running a school. The petitioners have challenged the allotment of this disputed land to respondent No. 8 by the Delhi Development Authority (hereinafter referred to as DDA, for short) primarily on the ground that as per the Zonal Development Plan (hereinafter referred to as ZDP, for short), the disputed land falls under the "recreational Zone" namely, "neighbourhood Park/ Green Belt". Civil Writ Petition No. 5862 of 1999 is filed by CU-Block Residents Welfare Association praying for identical relief. Accordingly, both these writ petitions were heard together and are being disposed of by common judgment.

( 3 ) FACTUAL background which led to the allotment of the aforesaid disputed land to respondent No. 8 is substantially undisputed and may be narrated at this stage. As per the layout Plan of the area in question, as it existed in the year 1995, two higher secondary schools (hereinafter referred to as HSS, for short) and one primary school were earmarked in the Plan and the land was to be allotted for this purpose. Land was allotted to Shree Agarwal Dharamshala Trust near DU-Block, Pitampura. Since, DU-Block site for the said HSS already contained a large number of grown- up fruit trees and other trees, objections were raised by the Horticulture Department of DDA not to allot the said site for school purposes as it would result in cutting of 169 grown-up trees. In view of these objections raised by Horticulture Department of DDA, the matter was considered by the Vice Chairman, DDA who deputed concerned officers to inspect the site and submit their report. After receiving the report. Vice Chairman, DDA felt it necessary to re-Plan the entire area and provide alternative site for HSS. A decision was taken to the effect that an adjustment Plan should be prepared. Based upon physical survey, an adjustment Plan was prepared. It was decided to retain the area where there were grown-up trees as green area and not to cut the trees and instead an alternative site was earmarked for allotment to HSS which was originally earmarked for "neighbourhood Park/ green belt" and it was ultimately this site (i. e. , the disputed site) which has been allotted to respondent No. 8. Thus there is a swapping of the two sites. The site which was orignally meant for "neighbourhood Park/green belt" was allocated for the. purpose of HSS and the site which was originally meant for school was allocated for the purpose of green belt. This change in the layout Plan has been carried out by the DDA.

( 4 ) CHALLENGING this course of action adopted by the DDA and consequentially allotment of disputed site to respondent No. 8, Mr. Parag Tripathi, learned Senior Counsel for the petitioner submitted that the change of site in the aforesaid manner amounts to violation of Delhi Master Plan - 2001 (hereinafter referred to as DMP- 2001, for short) as well as ZDP and, therefore, it could not be done without complying with the procedure contained in Section 11-A of the Delhi Development Act, 1957 (hereinafter referred to as the Act, for short) for which the Competent Authority is the Central Government.

( 5 ) HE further referred to para 9. 1. 3 of the draft ZDP of the area in question which reads as under :.

"according to MP-2201 norms, 204 H. S. S. are required for this zone whereas in all 123sites have been provided. These sites identified in the Zonal Plan and are as per details given below: - S. No. Sub-Zone Required Area (Ha) No. as As per ZDP Nos. perdp Area (Ha) 1. H-18 9. 057 2. H-2 15 24. 0 -11 10. 980 3. H-3 17 27. 20 11 21. 160 4. H-4