Aurora will break ground next Wednesday, Aug. 12, at 1 p.m. on a major dredging and shoreline restoration project at Mastodon Lake, the historic 28-acre pond at the heart of Phillips Park that has spent years silting up from stormwater runoff. The ceremony kicks off construction at the park, located at 1000 Ray Moses Drive, on a fix city officials say will dredge out decades of sediment and clean up the shoreline for good.
The Aurora City Council approved two contracts this spring totaling nearly $5.2 million with a single contractor, splitting the work into $4.6 million for hydraulic dredging and $576,183 for shoreline restoration, according to the Daily Herald. The project had originally been planned around a $5 million target budget before the final contracts pushed the total slightly higher, the paper reported. The Daily Herald identifies the contractor as Yorkville-based Semper Fi Landscaping Inc., though the City of Aurora's own groundbreaking announcement refers to the company as Semper Fi Land Services Incorporated, describing it as a local veteran-owned contractor.
Why the Lake Needed a Rescue
Built-up sediment from stormwater runoff had reduced the lake's water depth to no more than 2.5 feet in places, with at least 2 feet of muck sitting on the bottom, per that same reporting. The buildup choked aquatic life and fueled excessive algae growth, turning what was once a scenic centerpiece of the park into a shallow, murky pool.
Before committing to full-scale hydraulic dredging, Aurora had relied on chemical herbicides to control weed growth and vacuumed sediment near the Phillips Park Golf Course irrigation intake, according to DredgeWire. City staff eventually concluded those were only short-term fixes, since recurring weed blooms kept affecting the lake's appearance and golf course operations, the trade publication reported.
From Depression-Era Dig to Ice Age Discovery
Mastodon Lake itself dates back to 1934, when it was carved out as a Civil Works Administration excavation project during the Great Depression, according to Wikipedia. Workers on that federal jobs project unexpectedly uncovered ancient mastodon fossils while digging out the lake bed, which is how the lake got its name.
Those fossils included a 188-pound mastodon skull, a six-foot-long tusk and a 92-pound lower jaw, estimated to be 10,000 to 20,000 years old, according to the City of Aurora. They remain on public display at the Phillips Park Visitor Center, alongside bones from giant beavers and trumpeter swans that were also unearthed during that same dig, the city says.
Six Years of Planning, Now a Shovel in the Ground
City officials began planning the restoration back in 2018, formally laying out guidelines in a 2020 Mastodon Lake Stormwater Plan before hiring engineering firm HR Green to design the hydraulic dredging strategy, per DredgeWire's reporting.
The project is being funded in large part by a $4 million grant from the Illinois Department of Commerce and Economic Opportunity, easing the burden on Aurora's municipal stormwater management fund, the city said in its groundbreaking announcement. State Rep. Barbara Hernandez played a pivotal role in securing that grant funding, according to the city.
What the Restoration Will Actually Look Like
The shoreline work will include stabilized limestone outcroppings alongside native wetland and upland plantings designed to naturally filter incoming stormwater and stop bank erosion, per the city's announcement. City officials also plan to add stone access points for visitors, install directional circulators and aeration fountains, and completely reshape the lake bottom.
Those upgrades, officials say, are expected to greatly beautify Mastodon Lake and open up more recreational use of both the water and Mastodon Island. In the city's announcement, John Laesch said he appreciates city staff's work on the project and expects it to restore the lake while continuing to draw visitors from Aurora and beyond.
Heavy dredging machinery is expected to begin active sediment removal once next week's ceremony wraps, with full restoration targeted for completion in 2027, the Daily Herald reported.
Deeper Roots at Phillips Park
Mastodon Lake sits inside the 325-acre Phillips Park, established after former Aurora Mayor Travis Phillips willed $24,000 from his estate in 1899 to buy land for a public park, according to Wikipedia. The park has since grown to include a free zoo, golf course, aquatic center and sunken garden, in addition to the lake that gave the Depression-era dig its name.
