Water Water Everywhere #2 - Water Quality & Impact

Iowa’s native prairie and savanna had deep, rich, healthy soil with abundant microbiology and good infiltration rates.  Most rain soaked into the soil, recharging groundwater, that eventually fed our lakes and streams with clean water.  Now many roads, buildings and compacted lawns shed rainfall instead.  

In 

Water Water Everywhere #1 (too long ago to be a series...?) we went into changing land use in detail.  For this next part we will talk about how this effects water quality and pollution.

Increased runoff through a suburban development in Ankeny

With this increased runoff and flooding, this water now has the energy to pick up lots of trash and other pollutants.

Trash in Yeader Creek (and yes it looks like this every time it rains)
Photo courtesy of Julie Perreault – Polk Soil & Water Conservation District 

Along with garbage, water coming off parking lots, driveways and roads can be contaminated with gasoline, motor oil and heavy metals.  (Grass clippings and leaves in the street are also easily carried away, more about those later.)  These compounds, and toxic elements, breakdown slowly in the environment and directly threaten the health of people, fish and other aquatic organisms.  

Oil in parking lot at Easter Lake Park

Oil slick in Yeader Creek
Photos: Julie Perreault – Polk Soil & Water Conservation District 

Increasing water speed also creates erosion, damaging property and picking up sediment.  Sedimentation is a major contributor to water pollution by reducing water clarity and smothering habitat in streams and lakes.  Recreational lakes downstream may fill in with sediment and need to be dredged out, at considerable expense.  Sediments also carry with nutrients, especially phosphorus.

Eroded streambank near West Des Moines

Nutrients like nitrogen and phosphorus can stimulate harmful algae blooms and bacteria growth, reducing water oxygen levels and sometimes toxic on its own.  Grass clippings, leaves, pet waste and lawn fertilizers are other stormwater pollutants that contain high nutrient levels, as well as additional bacteria, that contribute to poor water quality.  All of thes factors can lead to fish kills and beach closures.

Half of Iowa state park beaches had swim warnings in 2020

Insects also love stagnant backwaters left behind as flood water recedes.  These pools are perfect breeding grounds for mosquitoes as predatory fish mostly follow the receding water back to safety of the lakes and streams.

A Plague of Giant Mosquitoes Rises Out of Florence Floodwaters

These swarms often cause even more contamination, as the cure is worse than the disease...

Effects of mosquito sprays on humans, pets, and wildlife

What's the buzz on mosquito sprays?

Watch for the next post in the Water Water Everywhere series (it hopefully won't be as long between) as we look at solutions for homeowners, farmers and anyone concerned about clean water.

Badger Creek at Sunset

#SlowItSpreadItSinkIt

Drake University Food Forest and Sprout Garden

New trees in the mixed orchard space at Sprout

Sprout: The Des Moines Urban Youth Learning Garden at Drake University was established in 2012 through the work of environmental science students and a grant from the State Farm Youth Advisory Board.  It serves as a community hub for environmental education and healthy food access for the neighborhood surrounding Drake University.  Produce from the garden is donated to the community through the Little Free Pantry, the Boys and Girls Club, and to students and volunteers.

Previous location on Forest Avenue

The Sprout Garden was originally located on Forest Avenue, near the Knapp Center and Boys & Girls Club, but due to new development the Sprout Garden had to be relocated.  The new location at 30th & Carpenter is a prime location as the gateway to campus.  The move also offered an opportunity for a redesign and introducing new features.  Through word of mouth and our previous work at DMACC, Abundant Design was selected for the project.

Campus "Gateway" on 30th St off University Ave

Meetings were virtual, budgets and timelines were tight.  Permits & getting approvals pushed back the start date, and approaching winter could put a hard stop on the installation.  Trying to reuse and bring over from the existing location as possible we took inventory of what we could salvage.  Ideas and possibilities were discussed among potential interested parties, with the current open space redesigned through several rough drafts into a food forest park, with permaculture tree guilds, runoff capturing rain gardens and gathering spaces.

Work began with new site prep, grading and rainwater catchment to hydrate the parched lot and manage stormwater.

Site assessment and beginning dirt work

Snow and rain helped confirm soil infiltration rates after construction

Student volunteers helped move native plants over to supplement the rain garden plantings.

Photo from the Drake University | Community Engaged Learning newsletter

Final overflow - three rain gardens double as On Contour Swales 

The garden shed was next, along with the rain barrel, and a new gathering/presentation space. Almost stadium style bench seating was built with the limestone brought over.  The existing gingko trees from the green space were moved into the parkway for street trees requirement.  This conserved budget and gave us lower growing trees as not to shade the garden production areas.

The Drake facilities team members were great to work with, and getting the shed and arbors moved.

That early first snow gave me a scare that the nice weather wouldn't last!

But luckily it did!

Garden beds were modified from the previous rectangular beds (seen above) to keyhole beds using the aged but mostly reclaimed lumber.  These keyholes allow for easier access to the plantings while increasing overall growing area, all with a smaller overall footprint.

Keyhole raised bed construction

Wood cores will give them an almost hügelkultur effect, feeding beneficial fungi and helping to retain/wick moisture.

Aged wood lined beds and fungal activity

At the end of Season one had the garden space moved and a great start on the mainframe of the forest garden park.

Arbor entry into the gardening area

Raised beds, in-ground grow space, fence with orchard behind

Teaching space with limestone benches off shed

You can follow the Sprout Garden on Facebook for gardening tips, community resources and volunteer opportunities.