Future development around Lake Whatcom must not put excessive amounts of phosphorus into the lake, according to new rules the Whatcom County Council approved on Tuesday, July 23.
The 6-0 vote enables the council to end an eight-year moratorium prohibiting subdivisions around the lake with lots smaller than five acres.
The rules met resistance from real estate groups, which estimated the needed stormwater controls would add at least $25,000 in development costs - too high a price for the small lots in Sudden Valley, they said.
About 700 vacant lots remain in the lake's watershed that are less than 10,000 square feet - most of them in Sudden Valley, said Mark Personius, the county's long-range planning manager.
Council member Sam Crawford agreed with development interests but voted for the rules anyway.
"This will probably have profound impacts to the future build-out of Sudden Valley," Crawford said in an email.
Runoff from future development may not add more phosphorus to the lake than the lot would if it remained forested. This "phosphorus neutral" requirement will most likely be part of a long-term cleanup plan.
The rules have been in the works for years but were spurred by a state report, released in February, requiring the county to come up with a plan within five years for cleaning up Lake Whatcom.
Excessive phosphorus runoff stimulates excessive algae growth, setting off a chain reaction that triggers more bacteria and robs the lake of oxygen. This harms fish while making algae concentrations high enough to slow the city's water filtration system during the worst periods.
Lake Whatcom is the water source for about 100,000 residents.
Council Chairwoman Kathy Kershner did not participate in the vote after she became ill at the meeting and was taken to St. Joseph hospital for dehydration. Kershner said in an interview on Wednesday, July 23 that she had fully recovered.
Kershner also said that would have voted in favor of the new rules, too.