To get in touch with Sarah Cayton or to find out more about Water Works Park, visit the Facebook page she started.Sitting on the concrete stage of the amphitheater at Water Works Park, Sarah Cayton said that if she looked out and saw 500 people filling the grounds in front of her, it wouldn’t be enough people.Instead, despite it being a sunny summer afternoon, there was no one around. Tall grass and weeds swayed in the breeze.It’s not surprising, considering many these days have forgotten the venue used to host Vancouver’s biggest public concerts and events. That was before the bandstand at Esther Short Park was fixed up. Before the bands, crowds and vendors flowed there.“People grew up and moved on, and this park was forgotten,” Cayton said of the park just north of Clark College.And by 2016, the amphitheater will be torn down to create a new 3 million gallon city reservoir. The site has never officially been a park, but rather part of Vancouver Water Station 1, which supplies more than 30 percent of the city’s clean drinking water.The entire upper portion of the site will be fenced off from the public. Plans keep Swift Skatepark and the northern portion of the grounds open.