The webs of hike and bike trails spanning Round Rock and Pflugerville help local residents recreate, but city planners said they have bigger intentions when designing park and trail systems.

City hike and bike trails and the parks they connect are a boon to new housing and a draw for developers, said Aileen Dryden, parks development manager with the city of Round Rock.

"A road doesn't sell you a house—pictures of trees and parks do," Dryden said.

Parks are what Dryden and her counterparts in Pflugerville aim to continue connecting with a growing constellation of hike and bike trails in the neighboring cities.

Parks and the trails that connect them promote physical activity, the vegetation removes harmful air pollutants, and help unite communities, according to a Round Rock Parks and Recreation Department economic benefit analysis.

Parks and trails also contribute to higher property values, according to the report.

"Homes purchased between 1997 and 2008 that were within 600 feet of a park paid a premium purchase price of 15.4 percent over those farther than 600 feet," the city report stated.

In 2010, Round Rock estimated the value added by parks to area homes at almost $152 million, which would account for more than $600,000 in increased property taxes, according to the analysis.

Round Rock voters passed a $56.5 million parks and recreation bond measure in November 2013. Among many improvements, the bond will pay for extensions to trails throughout the city, Dryden said.

Round Rock is constructing the Heritage Trail, among other projects, with the bond money. It forms a portion of the Brushy Creek Trail, which runs east to west through Williamson County and is expected to eventually connect one end of the county to the other. The trail will tell the history of Round Rock through signage, sculptures and more, Dryden said.

Certain trails are also considered as transportation routes. The Brushy Creek East Trail Extension, which is set to open in September near downtown, received a grant to help pay for its construction from the Texas Department of Transportation and the Capital Area Metropolitan Planning Organization because it qualified as an alternative transportation route, Dryden said.

Round Rock plans to bring its total of about 9 miles of trails up to 15 miles with the bond money, Dryden said.

Pflugerville already has nearly 50 miles of trails, Parks and Recreation Director James Hemenes said.

"Our residents have consistently listed more trails as a high-priority item," Hemenes said in an email.

Pflugerville City Council discussed preparing a November bond measure that would include money for more parks and trails during its July 8 meeting.

The city of Pflugerville's latest trails master plan outlines 18 priority projects that would cost about $9.5 million, Hemenes said.

The hike and bike trails that cities build can take a variety of forms. Some trails are paved, some are gravel, some follow the paths of creeks and others link to roads and take the form of 10-foot-wide sidewalks called street trails, Dryden said.

Residential developers also build trails in communities and can link to city trails.

Seema Gulati, a sales consultant with Gehan Homes in Avalon, said the developer-built trails in the Pflugerville community add value to homes in the area.

"The fact that people can hike and ride a bike from their home to the community pool, it's pretty good," Gulati said. "The parents don't have to give a ride to their kids. They can ride a bike."