To the editor:
The city’s plan to re-engineer Taylor Run to reduce phosphorus erosion is shortsighted because it fails to take into account the substantial value of the mature forest thriving along the stream in Chinquapin Park.
We agree with the city’s goal of reducing phosphorus pollution of the Potomac River and Chesapeake Bay. Excess phosphorous is an important cause of reduced oxygen levels in the bay and can cause algae blooms. Everyone agrees that the Potomac and Chesapeake have great value to the region, as an ecosystem and as a fishery, as well as aesthetic and recreational value.
If everything works as planned, the city calculates that its $4.5 million project will prevent a pound of phosphorus erosion for every $1,600 spent. While we have doubts about the accuracy of the calculation, pricing out the cost of phosphorus reduction is wise, since it can help the city choose the lowest cost option.
But the city’s calculation is fatally flawed because it gives zero value to Chinquapin’s mature forest and rare acidic seepage bog, which constitute a kind of museum of the forest. The city plans to remove virtually every tree near the stream, 269 in all, and to scrape off every shrub and plant near the stream, along with the topsoil, roots, rhizomes and the seed bank deposited over the decades.
One reason for the richness and diversity of the forest around Taylor Run is the rich, loose soil that has developed there from leaf litter over the last hundred years or more. The forest has protected the phosphates naturally in this soil and prevented it from running off in the rain. Another reason is the city’s success over the last 10 years in clearing most of the invasive species that might otherwise have choked out the native trees and plants.
The city maintains that by replanting saplings and shrubs, it can quickly restore Taylor Run’s environment. But creating a forest from scratch in the wake of bulldozers takes much more than sticking seedlings in the ground. It will take many decades for the tree canopy to return.
Some of the trees slated for death are more than 100 years old. The city’s heavy machinery will crush tree roots and transform the verdant soil around Taylor Run into compacted clay. Take a look at the compacted clay around Donaldson Run, a failed 10-year-old “stream restoration” project in Arlington. While some of the trees planted there are growing, virtually nothing else does in the tarmac-like soil. Redeveloping topsoil might take 100 years.
Just as Chesapeake Bay has environmental value, so does the rich forest in Chinquapin, a beautiful wild area near the center of Alexandria. Don’t ruin it. There have to be better ways to protect the Bay than to trash our parks.
-James Clark, Alexandria