Common open space. In the interest of providing for stormwater management facilities, ponds and required drainage facilities and preserving natural features and providing play or recreational areas, a development with the design alternative described herein may be planned with minimum size lots and common open space. The maintenance of land for common open space or recreational use shall be guaranteed by deed restriction, trust indenture, conveyance of the land to or for the benefit of all individual lot owners within the tract by compliance with the Pennsylvania Unit Property Act, or by other procedures for the management and maintenance of the common elements as may be approved by the Township Commissioners. Any or all such plans, agreements or instruments shall be filed with the Recorder of Deeds of Montgomery County simultaneously with the recording of the final plan of the subdivision. In the event of a material default as determined by the Township Engineer in the preservation or maintenance of land used for open space, ponds, drainage facilities or recreational use, the Township shall have the right to enter, preserve and maintain such lands and facilities and assess the cost thereof on the trustee(s) or, at the option of the Township, on the owners of the building lots and homes in the development, such charges to be proportional to the assessed values of the individual lots.