More than 40 years after the family of Russell Lee family donated a 7.7-acre parcel next to Foothills Park to Palo Alto with the goal of expanding the park's recreational and conservation opportunities, the city is preparing to open the land to the public.

The site, located near the Oak Grove Picnic Area, has remained largely out of public spotlight since the 1981 donation -- so much so that until recently, most city officials and City Council members didn't even know it belonged to the city. Aside from a small nursery, the site's chief attraction is a portion of Buckeye Creek that routinely gets battered by erosion.

In recent years, the chief function of the 7.7-acre site has been to serve as a quarry for developer and philanthropist John Arrillaga, who owns the adjacent property and who has been leasing the land from the city between 1996 and 2005. In 2012, Arrillaga made an offer to buy the site, surprising council members and staff who weren't aware of its existence. Rather than sell, the council swiftly moved to dedicate it as public parkland, add it to Foothills Park and send the Lee family a long belated letter of thanks.

Since then, staff have been evaluating options for the site and analyzing the hydrological conditions around Buckeye Creek. Last week, the Parks and Recreation Commission accepted the study and endorsed a staff recommendation to open the parkland to the public. The City Council is scheduled to consider this recommendation in the spring.

For council members, the site represents an unusual dilemma. Everyone at City Hall is in favor of getting new parkland and adding amenities to Foothills Park. At the same time, the gift from Lee family could end up costing the city millions of dollars in cleanup and restoration costs, according to a hydrology study recently completed by the consulting firm ENGEO.

The ENGEO study makes several recommendations for addressing the sediment deposits and enhancing the riparian habitat. One proposal focuses on the 7.7-acre site and the nearby Los Trampas Valley, where the study proposes creating a new floodplain by lowering portions of the parcel next to the creek channel.

This would "help dissipate peak flows, equilibrate sediment transport and enhance habitat," according to a new report from the Community Services Department. Trails could later be added in the floodplain area to allow visitors to access the creek and learn about the riparian habitat.

Another ENGEO recommendation would target the Wildhorse Valley in the creek's upstream area, where the study recommends building a new channel in what is now a grass meadow. This, according to the study, would result in significantly less flow and "minimal erosion" of the creek because the new channel would capture most of the flow, according to the report.

Together, the two projects are expected to cost about $9.5 million, according to staff. Given the steep price tag -- and the fact that the city's infrastructure plan already has a funding gap of about $50 million -- staff is recommending that future improvements focus exclusively on Wildhorse Valley. These would include adding the creek channel and retrofitting existing grade-control structures -- timber barriers and gabion baskets that according to ENGEO were installed 50 years ago and are "reaching the end of their life span."

The Wildhorse Valley work alone, however, would cost about $3.7 million. Given the lack of funding for the project in the city's budget, staff and the Parks and Recreation Commission are recommending pursuing outside funding for this work.

As a fallback option, staff is recommending adding $150,000 to the capital budget for design and permitting to replace the grade-control structures and the pedestrian bridge at the creek, across from the Foothills Park Interpretive Center.

Daren Anderson, manager of the Open Space, Parks and Golf Division in the Community Services Department, said that while funding challenges were a major factor in staff's recommendation, they weren't the only issue. There was also a concern among staff and commissioners about the scope of the proposed changes and the impact of construction on Foothills Park.

Widening the creek at Los Trampas Valley, for example, would permanently change the grass field in the valley, which according to Anderson individual visitors and groups use for recreation activities in the Oak Grove picnic area.

"The potential impact of doing full remediation of the creek -- both at Los Trampas and Wildhorse Valley -- would significantly change the look of the park," Anderson told the Weekly.

The proposed approach means that city's newest parkland will largely remain in its current state when it opens to the public later this year -- a hilly, largely undeveloped parcel with 2 acres of flat land that includes the nursery and a path leading to the creek.

The only costs that the city will have to incur before it welcomes the public to its newest parkland is $25,000 for fencing near the native-plant nursery and near the culvert at the creek.

Anderson's report notes that even though the 7.7-acre area doesn't have any park amenities, Oak Grove is only a short walk away and it includes parking, seating, a drinking fountain and a restroom. The report also notes that once the parkland is opened to the public, staff and the commission will "continue to collect feedback and work with the community to develop plans for best uses for the space."