Sunday, August 31, 2014
YOLO COUNTY NEWS
99 CENTS

Managing Northstar Pond: Aerators are unnecessary

Northstar Pond fountainsW

Two aerators in Northstar Pond are doing little to nothing to control algae or odors in the pond,. This photo was taken in September, after a summer of running the aerators all day, seven days a week. Andy Bale/Courtesy photo

By Andy Bale

Warm weather is coming and algae mats have begun to grow on Northstar Pond again. Parks management and experienced staff know that the industrial-style aerators in place the pond do nothing to improve the pond’s overall water quality or control algae. They have told me so.

However, the Parks Department will be under pressure to run the aerators in the pond all day long as they have in summers past. They should resist this pressure and, instead, look for an effective solution to the pond’s water quality problems and neighborhood concerns.

It likely costs the city about $10,000 a year to run the aerators and, over the years, total costs are likely more than $100,000 — a huge waste of money and resources. Unfortunately, a small group of citizens insists that the aerators control algae in the pond, and they are very vocal. So, Parks continue to run the aerators because, as one manager told me, it is cheaper and easier than dealing with the many calls of complaint that these citizens generate. Rewarding this kind of harassment doesn’t seem like either a fiscally or socially responsible approach.

While aerators have a place in water quality management, they are inappropriate and ineffective in Northstar Pond. In deeper ponds, aerators can provide oxygen to bottom water that is cut off from the atmosphere. They can create circulation, and they can break up algae mats.

But Northstar Pond is very shallow and broad, with no horizontal circulation. Here, the aerators simply churn water and do nothing to control algae or odors in the greater pond. As shown in photos accompanying this column, algae cover the pond right up to the edge of the aerators despite their continuous operation. The photos were taken in September, after a summer of running the aerators all day, seven days a week.

More than 90 percent of the pond is unaffected by the aerators. Besides, being very shallow and full of aquatic plants, it’s unlikely that the pond suffers much from lack of oxygen.

Nearly seven years ago, I was asked by a neighbor to help her negotiate with the Parks Department about the aerator schedule. She lived right on the pond and, for her, the sound of the aerators all day long was unbearable.

As anyone knows who has been near them when they start or stop, the aerators really are loud. Over these many years of talking, she and I have come to agreements with Parks and seen them broken without explanation. Nothing’s been resolved for long, but I have come to understand the issues well.

There are two: the aesthetics of “fountains,” and seasonal warm-weather growth of algae mats (or, pond scum). As a start, Parks should clearly separate these two issues because fountains in this pond have nothing to do with algae growth.

Some people, not everyone by any means, want to see a water feature in the pond. Personally, I prefer the pond natural and quiet. But if there is a strong desire for a water feature, and there are funds to purchase and run it, I’d support a pleasant well-designed fountain.

Controlling algae is a more complicated problem to resolve. And, it’s not clear that everyone would want seasonal growth of algae controlled. Many people may be fine with a naturally eutrophic pond that grows algae in the summer and is clear in the winter. Any effective approach to managing algae in the pond is likely to be costly and will require significant commitment of time and funds.

Basically, to control algae in the pond, Parks needs either to kill them, remove them or inhibit their growth. There are many approaches. Based on discussions with neighbors and colleagues, here is a list of ideas that Parks might consider:

* Rake and remove surface algae regularly;
* Drain the pond, dry its sediments and scrape the bottom to remove nutrients that have built up over the past 20 years;
* Treat the pond to increase color and reduce light penetration;
* Treat the pond to kill algae;
* Create an outlet and periodically fill and drain the pond to remove suspended nutrients. This outlet also could be used to skim off and break up surface algae as studies in UC Davis Arboretum have shown;
* Create an attractive waterfall with a natural rock filter on the island in the pond;
* Install a sprinkler system or moving fountain that could break up surface algae throughout the pond; and
* Design habitat to filter pond water. Originally, the pond was designed so that pond water was used to irrigate surrounding vegetation. Reinstate this design and create habitat on the pond perimeter as a natural filter system to remove organic matter.

Parks officials would be well served to focus their limited resources on establishing a long-term plan for the pond. With community involvement, Parks should determine what kind of pond the city wants, and can afford, to maintain.

A good management plan will require work, and its effectiveness will depend on the Parks Department’s commitment. But I believe that Parks can find an approach that will resolve every reasonable concern about water quality, aesthetics and noise in Northstar Pond. Parks should take serious steps in that direction.

— Andy Bale has lived in the Northstar neighborhood for the past seven years. He holds a Ph.D. in civil and environmental engineering from UC Davis and has specialized in surface water quality and numerical simulation for more than 25 years.

Comments

comments

Special to The Enterprise

.

News

 
Davis audience hears from civil-rights hero

By Anne Ternus-Bellamy | From Page: A1 | Gallery

 
Legislators wrap up with water, ethics, guns bills

By The Associated Press | From Page: A2 | Gallery

 
Bob Dunning: This new kid might have a future

By Bob Dunning | From Page: A2

Five U.S. airstrikes target Islamic State fighters

By The Associated Press | From Page: A2

 
EU threatens Russia with more sanctions

By The Associated Press | From Page: A2

Rotary clubs offer Davis High students some life lessons

By Evan Arnold-Gordon | From Page: A3 | Gallery

 
Robbery, pursuit in Central Davis lead to one arrest

By Anne Ternus-Bellamy | From Page: A3

Dinner will raise funds to help farmers in Burkina Faso

By Enterprise staff | From Page: A4

 
Walkers welcome to join Sierra Club outings

By Enterprise staff | From Page: A4

Beamer Park featured at Stroll Through History

By Enterprise staff | From Page: A4

 
Yolo Federal to hold photo contest

By Enterprise staff | From Page: A4

Katehi will speak at Chamber’s community luncheon

By Enterprise staff | From Page: A4

 
Bean Feed supports for Yolo Democrats’ activities

By Enterprise staff | From Page: A4 | Gallery

 
Bauer garden marks one year

By Special to The Enterprise | From Page: A4

Tuleyome Tales: Be safe on wilderness trails

By Special to The Enterprise | From Page: A5 | Gallery

 
Small wineries suffer big losses in quake

By San Francisco Chronicle | From Page: A6 | Gallery

Grande site has been a convoluted saga

By Jeff Hudson | From Page: A7

 
Say goodbye to summer with a ‘Final Blast’ at Explorit

By Enterprise staff | From Page: A9 | Gallery

 
Bay Bridge project’s rainy-day money is nearly gone

By San Francisco Chronicle | From Page: A15 | Gallery

.

Forum

Already made herself at home

By Creators Syndicate | From Page: B5

 
Keep our green waste piles

By Letters to the Editor | From Page: A10

How to make a good living

By Letters to the Editor | From Page: A10

 
Nate Beeler cartoon

By Debbie Davis | From Page: A10

Changing local election dates benefits Democrats

By Tom Elias | From Page: A10

 
Ad-free email? You can still find it at Davis Community Network

By Special to The Enterprise | From Page: A10

City panel working to tighten scrutiny of taxpayer dollars

By Special to The Enterprise | From Page: A11

 
Try round-robin storytelling at crafts fair

By Special to The Enterprise | From Page: A11

Speak out

By Enterprise staff | From Page: A11

 
Health problems mean he’s checked out

By Creators Syndicate | From Page: A14

Marriage doesn’t mean we agree on everything

By Marion Franck | From Page: A14

 
This epidemic should scare us

By Special to The Enterprise | From Page: A14

.

Sports

New coach, new tougher league for DHS football

By Thomas Oide | From Page: B1 | Gallery

 
Coach likes what she sees from Devil field hockey squad

By Enterprise staff | From Page: B1 | Gallery

UCD notebook: Coaches positive about FCS schools ‘playing up’

By Bruce Gallaudet | From Page: B1 | Gallery

 
Devils open with an impressive volleyball victory

By Spencer Ault | From Page: B1 | Gallery

Stanford scores early, often in opener versus UCD

By Bruce Gallaudet | From Page: B1 | Gallery

 
Sports briefs: Aggie harriers secure season-opening sweep

By Enterprise staff | From Page: B2 | Gallery

Baseball roundup: Cats win late to pull even with Aces

By Staff and wire reports | From Page: B8

 
.

Features

.

Arts

.

Business

Comings and Goings: Is fro-yo craze melting?

By Wendy Weitzel | From Page: A13 | Gallery

 
Sutter Davis Hospital honored again as a ‘best place to work’

By Special to The Enterprise | From Page: A13

Community pools its purchasing power to reduce the cost of solar

By Special to The Enterprise | From Page: A20

 
Engage3 attracts investment for shopping app

By Enterprise staff | From Page: A20

California growers can use MBI’s new bioinsecticide

By Special to The Enterprise | From Page: A20

 
Sudwerk, Davis Food Co-op join for ‘co-hop-eration’ brew

By Special to The Enterprise | From Page: A20 | Gallery

.

Obituaries

Wanda P. Daley

By Special to The Enterprise | From Page: A4

 
.

Comics

Comics: Sunday, August 31, 2014

By Creator | From Page: B8