San Diego County crews began construction Friday on a $11.2 million project intended to rejuvenate and improve Lakeside’s popular Lindo Lake County Park. Improvements at the 55-acre park will include a new fishing pier and birdwatching stations, hundreds of native trees and improved water quality in the lake’s east basin by removing more than 200,000 tons of sediment — enough to cover nearly five football fields 12 feet high — which has accrued for decades.