LYNN – Gus Stiros looked out his porch window on a rainy day last December and asked, “Where the heck are my lilac bushes?”He found the answer a couple of minutes later when he walked outside and realized the stone wall at the end of his yard had collapsed into neighboring Cook Street playground, carrying away 30 feet of his lawn and his lilac bush.City workers shored up the collapsed wall and removed debris, but permanent repairs – including restoration of Stiros? lawn – are still months away. The work will begin in early summer with an engineering study aimed at determining the best and safest way to restore the collapsed wall and prevent another collapse.?At the end of the day, it will be done and last another 100 years,” said city Public Works Commissioner Andrew Hall. Carved out of hilltop near the top of the Highlands, Cook Street playground has an upper-level garden area reached by concrete stairs and the main park with its ball courts and play equipment.The Dec. 9 collapse, likely caused by several severe rainstorms, spilled dirt and wall debris into an area where workers had started to install new playground equipment as part of a citywide park and playground restoration program. No one was injured in the collapse, but the wall repairs must be done before the installation work can resume.?If this had happened during the middle of the summer, we would have been digging kids out,” Stiros said.He credited the city for promptly taking responsibility for restoring the wall. City workers piled boulders at the base of the collapsed wall to serve as a buttress and prevent another section of Stiros? lawn from spilling into the playground.They also built a wood shoring structure to ensure Stiros? wall section facing Cook Street does not collapse. His home is perched about 60 feet above the street and the playground.?Now it seems stable. I give them credit – they took ownership right away,” said the 20-year Highlands resident.Hall said the DPW budget includes $100,000 to repair the wall, and he is confident the work can be completed this summer. In addition to completing the playground installation, Hall said Cook Street needs improvements to its ball courts or, at least, short-term repairs – workers peeled back court fencing so they could haul in the boulders from Wilson Street.Hall said Highlands Coalition community group members are “keeping an eye” on the area of the collapse.