building new walkways, paving dirt roads, creating playgrounds, and installing lights. Baseball, soccer, and cricket fields were added in 1938. The Van Cortlandt Stadium was added in 1939 on the site of a former swamp, and a pool followed in 1970. Moses also landscaped the areas near the Woodlawn and 242nd Street subway stations to attract park visitors from other neighborhoods. During his tenure as Parks Commissioner, Moses took aggressive approach to preserving the park's quality. For instance, six mothers were issued court summonses in 1942 after letting their children dig in the park, and two airplane pilots were fined in 1947 for unauthorized airplane landings. Around 1939, the old aqueduct, which was now a popular hiking trail, started becoming a popular route with cyclists. Soon after, there was a proposal to redevelop the trail as a bike path. This proposal never came to fruition, although in the mid-1970s, the city built a separate bike path along Mosholu Parkway, the Bronx River Parkway, and Pelham Parkway between Jerome Avenue and Pelham Bay Park. Decline By the 1960s, large portions of the park, such as Tibbetts Brook, were being polluted by human activity; in addition, the brook now flowed into the Broadway sewer at the south end of Van Cortlandt Lake. Pollution from upstream and the highways, and spillover of chemicals used in the golf course, killed fish in the lake. This problem was first noticed in May 1961 when thousands of dead bass, pickerel, catfish, perch, and carp floated up at the edge of the lake. The mass-death of fish was blamed on siltation, Three years later, fish were still being killed by siltation. City investigators took water samples from the lake and found that they contained large amounts of weeds and sediment. About of the lake's surface area was being lost to sedimentation every year. In addition, an algal bloom caused the lake to be in a low-oxygen condition, endangering plants and animals in and around the lake. "Unpleasant odors" in the summer also reduced recreational opportunities on the lake, and these conditions combined made it virtually impossible to come into contact with the lake's water without getting sick. By 1976, there was a moratorium on all boating activities on the lake. The Van Cortlandt Golf Course was used as a ski slope during the winters starting in 1961, and up to 3,000 visitors would use the slopes each