SAN DIEGO (Border Report) -- Many horse and hiking trails throughout the Tijuana River Valley remain posted with warning signs advising people to stay out of the area due to ongoing sewage flows from Mexico. Tijuana River Valley Regional Park Campground, a popular county campground in the Valley, initially damaged by winter storms, has remained closed since January due in part to the pollution. The trails leading in and out of the campsite are off limits because water tainted with raw sewage continues to flow onto trails used by people and horses. San Diego County rejects shot at millions of dollars to clean polluted Tijuana River Valley The County of San Diego says the campground will reopen as soon a berm is fixed by the city of San Diego. The repairs are expected to keep the sewage out. “We are coordinating with the city of San Diego, they are repairing a berm damaged by the Jan. 22 unprecedented storm and impeded by ongoing TJ River flows. When that work is done, we can reopen," read a county statement. The Tijuana River Valley Regional Park Campground and Border Field State Park are impacted by the raw sewage that flows in from Mexico on daily basis. (Salvador Rivera/Border Report) Next door to the camp facility is Border Field State Park operated by the state of California. But it, too, has been closed for more than a year. The main road that leads visitors into the park is constantly flooded with water tainted by raw sewage. At its entrance, several signs warn visitors not to enter and to avoid any contact with water in the park. McLain Parker manages Ponyland in the Tijuana River Valley. (Salvador Rivera/Border Report) Many horse operations in the valley are also affected, including Ponyland, which offers trail rides in the Valley and out to the beach. "It's a shame, you got the hills, the flower fields, and the beach is absolutely beautiful," said McLain Parker, manager at Ponyland. But Parker says many trails remain closed limiting where the horses can go. You got that runoff, and that is a big issue.” Border Report Live: How Mexico water woes impact the US border Parker says the effluent in the Valley keeps many visitors away, hurting business. Some of the horses at Ponyland in the Tijuana River Valley. (Salvador Rivera/Border Report) "It’s sewage running through a state park that kind of speaks for itself, anywhere in the country they would not let that happen, they would send people out to take care of it, but down here they just kind of like ignore it.” Visit the BorderReport.com homepage for the latest exclusive stories and breaking news about issues along the U.S.-Mexico border Parker added that if they ever figure out a way to keep the sewage out of the Tijuana River Valley, many of the businesses in the area would flourish. "If it weren’t for the sewage problem it would probably be one of the best parks in the state."