Green Infrastructure (Stormwater Management Mandates)
This might look like a typical parking lot, but it was updated with environmentally-friendly features in 2024. Why? When it rains, water flows across the pavement carrying toxic pollutants like automobile oils and fluids, tire dust, and animal feces toward Lodi Lake. It's called "stormwater."To protect the water quality of the lake, Green Stormwater Infrastructure (GSI) filters the stormwater to remove pollutants and trash before it hits the lake. Notches in the curbs known as "curb cuts" direct water into a rocky swale: a shallow trench lined with stones. The rocks slow the flow of water and spread it out, letting it soak into the soil where biota and plant roots filter out pollutants.These features help the City of Lodi comply with the Environmental Protection Agency (EPA) and the California Environmental Quality Act (CEQA) stormwater regulations, which require state and local agencies to take action to reduce stormwater pollution to protect rivers, lakes, fish and wildlife habitats. This GSI system is part of a larger effort to safeguard the Mokelumne River and Lodi Lake for all species, including humans, to enjoy.
Grape Festival at Lake Lodi
The Grape Festival is Lodi's most popular annual event, attracting tens of thousands of visitors each September to celebrate the grape harvest. Today, it's held at the Lodi Grape Festival grounds, but did you know that it used to be at the lake? Originally called the "Tokay Festival," the event began in 1907 to celebrate Lodi's incorporation as a city and its famous Tokay grapes, which were known for their reddish-yellow color and sweet, crisp flavor. The first official Grape Festival was in 1934, just after Prohibition ended. In 1949, the festival moved to its current location at the Grape Festival grounds.
Annual Rabbit Hunting Drive
In the early 1900s, farmers around Lodi Lake organized "rabbit drives" as a way to reduce the rabbit population. They invited hunters to help clear out the rabbits, which had become a serious problem for local crops. The drives became annual social events with lunch and prizes.While these hunts seemed like a practical solution at the time, the farmers and hunters didn't fully consider their environmental impact. Rabbits serve as prey for native predators like hawks, foxes and coyotes, and rabbit holes serve as homes for other ground-dwelling species, such as burrowing owls. It has often been the case that humans misunderstand integrated systems, making our environmental management flawed. Continuing to learn and improve ecosystem knowledge leads to improved management.
Smith's Lake
In 1875, early settler Charles Edward Smith bought 80 acres of land from Captain Alexander McQueen on the south side of the Mokelumne River. Smith initially farmed onions and flax on the land; by 1885, he had also established a vineyard and built a home for his family. In 1889, the construction of Woodbridge Dam expanded a small seasonal pond — the early Lodi Lake — into "Smith's Lake," named by his youngest daughter, Estella. The Smiths welcomed the public to enjoy the lake and it became a popular spot for rowing and recreational gatherings.After Charles’s death in 1902, Estella continued to manage the land. She was known for her willingness to defy societal norms. At a time when most women did not participate in farming, she hitched up and rode her own horses, taking an active role in running her land. In 1910, she sold some of the land surrounding the lake to a Mr. Potter, who had plans to develop it. However, those plans never materialized, and Potter later sold the property to Louis T. Mason.The Mason family built an estate on the land, naming it "Home Lake," and established a fruit company on the property. After nearly 25 years, Mason sold the lake to the city of Lodi in 1934 for just $7,924, far below its estimated value of over $31,000, specifically with the understanding it would become a public space. The city renamed the area Lodi Lake Municipal Park.
How does Lodi Lake get filled?
The Mokelumne River to the north fills Lodi Lake. As the river moves downstream from the Nature Area, it reaches the concrete Woodbridge Diversion Dam. The dam blocks some of the river’s flow, causing the water to collect behind it, creating Lodi Lake.Every year in late February, the Woodbridge Irrigation District (WID) temporarily lowers the dam, draining the lake completely and leaving it looking like a mud pit. Any fish in the lake usually move downstream with outgoing water; if they get trapped, they make easy treats for the pelicans and egrets. WID uses this time for maintenance on irrigation canals and fish screens that normally have water flowing through them. After about four weeks, they raise the dam again and river water recreates the lake, filling up to its usual 12-foot depth.
History of Lodi Lake
Lodi Lake began as a small seasonal lake formed by the Mokelumne River flooding during the winter. In 1889, a group of farmers established the Woodbridge Canal & Irrigation Company and built a wooden dam along the river to provide irrigation for their crops during the summer months. As a result, the lake expanded and became known as Smith’s Lake, named after Charles Smith, who owned 80 acres of land around it. His daughter Estella, who took over lake management after his death, welcomed visitors to enjoy rowing, swimming and picnicking.In 1910, the lake grew even larger when the Company built a concrete dam to better control the water supply throughout the year. In 1934, Louis T. Mason sold the lake to the City of Lodi for $7,924.39, with the condition they use it as a municipal park. In the 1930s and 40s, the City expanded the park further as landowners gifted or sold surrounding parcels of land to the City. Over the years, Lodi Lake has hosted iconic events, including the Grape Festival, Independence Day fireworks and community celebrations, solidifying its place as the heart of local recreation.There was a short-lived plan to turn Lodi Lake into a California State Park, but that plan stopped when a developer built luxury housing in the middle of the potential park land. In the 1970s, there was another push by developers to turn the Nature Area into a golf course, but local activists successfully opposed the plan at a City Council meeting. Since then, the lake has been preserved as a haven for both people and wildlife. Today, Lodi Lake is a cherished public recreation space, offering trails, boating, and an opportunity to connect with nature.
Discovery Center
This is the Lodi Lake Discovery Center, a gateway to the lake’s scenic nature trails. Inside, exhibits highlight the Mokelumne River ecosystem and local wildlife, featuring mounted specimens and vintage photos of Lodi Lake’s history. The Discovery Center is also home to the Lodi Lake Docent Council, established in 1986.For nearly 40 years, docents (trained volunteer educators) led guided tours and shared their knowledge and enthusiasm for the lake with thousands of visitors. Their work fostered a deeper appreciation of the lake’s unique ecosystem. Unfortunately, the docent program paused in 2020 due to COVID-19, but its legacy continues to inspire a love of nature and a connection to the lake. If you are here on a weekend, be sure to take a look inside the Discovery Center — you’re guaranteed to learn something new!
Penn Mine Disaster and Massive Fish Die-off
Fish kills (or fish die-offs) are signs of serious environmental distress in rivers and other bodies of water. Common reasons for fish kills are human sewage and agricultural fertilizerscausing algae blooms and deoxygenating the water. Another common cause is contamination from mining in upper watersheds.For the Mokelumne River, toxic sulfuric acids left in the soil from the Penn Mine killed off fish and aquatic life several times over the decades, effectively sterilizing the river for a year or two. The Penn Mine operated primarily as a copper and zinc mine between 1859 and 1953. Miners used acids to leech the metals out of ore and kept these acids in ponds, which also caused acid build-up in the soil. During years of intense rain, the runoff would make it to the river, polluting the water and killing fish and other aquatic life.Though this was a regular phenomenon after 1953, it took decades for different enforcement agencies and public interest groups to win in court to clean up the mine site. There were many attempts at reducing runoff starting in the 1970s, but it wasn’t until around 2000 that East Bay Municipal Utility District (EBMUD) paid $10M to remove 360,000 cubic yards of contaminated dirt. Sadly, this type of residiual and active contamination is a common problem in rivers all over North America, as is the need to repeatedly take legal measures to force clean ups.
Lodi's Water Supply
Next time you take a sip of water in Lodi, think about this: you're drinking a blend of river water and 40-year-old "groundwater." The city’s drinking water comes from two main sources: the Mokelumne River and groundwater. After it rains, it takes 40 years for the surface water to percolate through the soil to underground aquifers, where wells then draw it up for use — this is called groundwater.Unfortunately, due to over-extraction, there’s no longer enough groundwater to meet demand. Since 2003, the city has purchased 6,000 "acre-feet" of Mokelumne River water from the Woodbridge Irrigation District (WID) annually, at a cost of $1.2 million per year. WID has the oldest water rights on the Mokelumne River, meaning it's allowed to use or sell water from the river. Most cities along the river have no such access, so the City of Lodi could not draw water from the river without purchasing it.To put it in perspective, one acre-foot of water covers an entire football field with one foot of water, and the city consumes 14,000 of these acre-feet per year. Water from the river flows to Lodi Lake’s treatment plant, where it’s cleaned and blended with groundwater for distribution. This treated river water makes up 40% of Lodi’s drinking water.
Surface Water Treatment Plant
If you've ever turned on a tap in Lodi, you've been using water treated right here at the Surface Water Treatment Plant. Since the 1980s, Lodi has nearly doubled its population, so relying solely on groundwater has become unsustainable. The City needed a way to ensure a long-term water source. Since the plant opened in 2012, it has processed up to 10 million gallons of Mokelumne River water daily, meeting 35% of the city's needs.The Surface Water Treatment Plant uses cutting-edge membrane technology to filter out harmful bacteria and parasites, which makes the river water safe for us to drink. Lodi can use Mokelumne River water thanks to a 40-year purchase agreement ($1.2M/year) with the Woodbridge Irrigation District, who holds the oldest water rights on this river. Without this arrangement, Lodi wouldn't have access to the river water.
History of Woodbridge
Woodbridge, the small town that borders on Lodi Lake, has deep roots in California’s history. In 1852, a man named Jeremiah Woods set up a ferry crossing on the Mokelumne River, making it a popular spot for travelers between Stockton and Sacramento. Later that year, Woods built a toll bridge at the old ferry crossing, charging $1 for a wagon with a pair of animals. Hence, the town’s name eventually changed from "Woods Ferry" to "Woodbridge."In the late 1800s, locals hoped Woodbridge would become the main city in the area. However, when the railroad went through nearby Lodi, Woodbridge stayed smaller and quieter. Today, Woodbridge keeps its charm with historic brick buildings along Lower Sacramento Road, including former fraternal halls like the I.O.O.F. Hall (1861), the Masonic Lodge and the Woodbridge Grange, which is now a community center. The Woodbridge Wilderness Area, right on the banks of the Mokelumne River, is a favorite for birders and fishermen. It’s a peaceful place with a rich history right next door to the hustle of Lodi.
Fish Ladders
After the construction of the Woodbridge Dam in 1910, the new dam blocked salmon and steelhead trout from reaching their upstream spawning areas to which they return each year. When those species lose access to upper watersheds, they can't reproduce. To help fish bypass the dam and continue their natural lifecycle, a “fish ladder” was installed in 1925. (Although it’s called a “ladder,” this structure is more like a series of small waterfalls, allowing fish to jump up from pool to pool to navigate past the dam.)The fish ladder at Woodbridge Dam is the only one along the Mokelumne River that allows fish to swim past a dam; Pardee Dam and Camanche Dam do not allow fish to cross, effectively halting their upstream journeys. The East Bay Municipal Utility District (EBMUD) now maintains the fish ladder at Woodbridge Dam and has redesigned it several times to increase effectiveness, with its latest upgrade in 2004. The new ladder has smaller steps to ease the climb, a path for fish to swim downstream, and screens to prevent them from being diverted into the Woodbridge Canal. To monitor fish migration, the dam has underwater cameras so EBMUD staff can count each fish as it passes through the ladder. 2024 saw a new record as nearly 30,000 Chinook salmon passed through the ladder!
Woodbridge Dam/Woodbridge Irrigation District
In the late 1800s, local farmers sought steady water supply from the Mokelumne River to support Lodi’s growing agriculture. In 1889, they formed the Woodbridge Canal & Irrigation Company. In 1891, they constructed a wooden dam to collect and store water for the dry season, channeling it through 24 miles of canals to farms for irrigation. This structure enlarged what had been a seasonal pond into a lake, now known as Lodi Lake. Although the lake was initially designed for agricultural water storage, it quickly became a favorite recreational area for the community.After a flood destroyed the dam in 1895, the Company built a sturdier concrete dam in 1910, but seasonal water flow continued to be a challenge. The Mokelumne River swelled with snowmelt in spring, then dropped to nearly zero by late summer, leaving farmers short on water during dry months. Realizing they needed more control over water access, farmers formed the Woodbridge Irrigation District (WID) in 1924. WID purchased the dam and water rights but faced many legal disputes with the East Bay Municipal Utility District (EBMUD), which controls the Mokelumne River's flow through its large dams upstream. Ongoing negotiations reflect the complexity of water rights: where shared, finite resources often lead to disputes. Today, WID serves Woodbridge, Thornton, and parts of Lodi and Stockton.
