Stormwater mapping: A glimpse into the world of tracking where the rain goes
Crossposted from The Downstream Blog
Aeronautical engineers, consultants, graphic designers, and Geographic Information System (GIS) professionals formed an unlikely, but unstoppable, team at King County’s Water and Land Resources Division last year. The project team’s short-term goal was to map the stormwater drainage system within parts of unincorporated King County, an assignment that allowed them to test their field skills and environmental passion. To help accomplish this, a team was brought together as part of an ongoing effort to map stormwater drainage system that had not been inventoried, as required by King County’s Phase 1 Municipal Stormwater Permit. Team members were hired for their knowledge of stormwater management and GIS, as well as a love of the environment. Their diverse backgrounds helped them each bring different skills to this project.
“This was a great opportunity to get a foot in the door at King County,” said Anna Lucero, one of the first mappers hired onto the team.
A team of about a dozen people was hired to locate, map, and inspect stormwater structures along nearly 800 of the 1,400 miles of roadways in unincorporated King County. The team started their days dispersing across the county to map and inspect nearly 65,000 stormwater structures and mechanisms, including pipes, ditches, catch basins, manholes, and other drainage features. The team would verify that these structures were not full of debris, cracked, or otherwise deficient, allowing water to continue to move smoothly throughout the stormwater system and help reduce flooding. To give a sense of magnitude of the stormwater infrastructure within King County, King County Roads Division estimates there are more than 5,000,000 linear feet of ditches, more than 25,000 catch basins, and more than 2,000,000 linear feet of pipe.
“The data needed a lot of work,” said Joe Espinosa, the project lead. “(It) hadn’t been updated in more than 15 years.”
A day in the life of the temporary mappers would start with the team strategizing their game plan for the day and making computer updates to the mapping work from the previous days. They would review the updated maps, determine what areas still needed to be mapped or reviewed, and would venture out with a teammate in a truck, traveling to their designated area to spend the day. “Having a partner in the field built great comradery among the team,” said Chris Meder.
Within their designated area, the mapping team would inspect each catch basin, measuring its dimensions, and assess if there were any large cracks or deficiencies in the structure. Using mirrors on sticks, they inspected the pipes coming in and out of each catch basin.
“I put a mirror down into a pipe one day and saw a skunk tail pointing at me,” said Jeff Tarshis. “Needless to say I wrapped up that inspection pretty quickly.”
Culverts were also a common stormwater conveyance structure that the team inspected. A culvert is a pipe or concrete box structure that drains to an open channel, swale, or ditch under a roadway or embankment. It is important that these culverts are not clogged with debris and do not have any breaks in the pipe or structure so water can move smoothly and quickly through the structure, therefore reducing flooding.
“One of my best field memories was when I inspected a culvert and saw two kittens in there,” said Emily Davis. “The kittens did not appear hurt but were quite playful and keen on diverting our attention.”
The team explored the widespread geographical areas of King County, the 13th largest county in the United States, which included summer field work on Vashon Island, winter trips to Enumclaw in the snow, and foggy fall trips to Duvall. Over the course of the short-term project the crew of 16 assessed nearly 27,000 stormwater structures and, of those, more than 5,000 structures were flagged for further investigation.
One surprise on the job was how interesting stormwater is within our environment.
“I came into the job wanting to expand my GIS skills,” says Chris Meder. “I came out stoked about stormwater management.” This short-term project provided the team with a boots-on-the-ground understanding of how rainwater flows through our communities and how extensive the stormwater infrastructure is in King County. The field work provided the mappers with real-world experience in understanding how stormwater pollutes our local waterways — an invaluable lesson since stormwater is the predominant source of pollution threatening the health of Puget Sound.
Getting out of the office and having this field component was a draw for many on the team.
“I love field work,” said Emily Davis. “It was satisfying to go out and get a lot of work done, regardless of weather.” Physically, the project gave the team experience in dealing with challenges of weather because they were out in the field mapping each week, rain or shine.
“I learned to always wear rain pants when it is raining,” said Taylor Rulien, “because just wearing a rain jacket doesn’t always keep you dry in our rainy season.”
This job also helped the team field test their knowledge of water systems in the real world, which requires an engaging mind to appreciate and understand.
“My educational background in engineering and my inquisitive mind for water systems helped me in this job,” said Melissa Dahl.
In addition to field and GIS skills, the project also provided numerous non-technical skills, including how to work together in a team setting, transferring outdoor data collection into online data tools, and building community relation skills.
“The public was so supportive of this project,” said Anna Lucero. “Everyone was very understanding and interested to learn that the rain does not go into the same pipes as their sewage. Everyone cared.”
This stormwater mapping project helps King County save time and money by minimizing emergency responses and road or property damage. Mapping and inventorying these structures provides data to make better decisions on stormwater infrastructure investments for a county of more than two million residents. And, with more knowledge about where the stormwater runoff goes and how it gets there, we can continue to clean up our lakes, rivers, and streams by looking upstream at potential sources of pollution.
Many of the team members were uncertain about applying for the project’s positions because of the short-term nature, but they were all glad they did it.
“I knew it was risky going from a full time consulting job to this, but it was exciting to jump into the unknown,” said Emily Davis. “This short term position pushed us to learn more and not be sedentary in a career.”
“This is the first job I have ever been sad to leave,” said Kasim Salahuddin.
“This job has helped shape my future,” said Melissa Dahl. “King County gave all of us a great opportunity and we are so appreciative.”
Keep an eye out for future internships, short term jobs or sign up for alerts at Careers at King County.