Toxic al­gae threat­ens Delta, Sacramento area wa­ter­ways

Lodi News-Sentinel - - STATE / NATION - By Caro­line Ghisolfi

The lake vis­i­tors call the “gem of Chico,” the lo­cal go-to lo­ca­tion for a quiet and re­lax­ing day trip on the water­front, is in­fested with toxic al­gae, of­fi­cials say.

The Butte County Public Health Depart­ment warned peo­ple on Mon­day to stay away from Horse­shoe Lake af­ter colonies of mi­cro­scopic cyanobac­te­ria grew out of con­trol and ‘bloomed’ into toxic and po­ten­tially lethal al­gae, poi­son­ing the wa­ter­way.

Harm­ful al­gae blooms, or HABs, are not new to the area — or to the Cen­tral Valley. This is the sec­ond alert of fresh­wa­ter HABs recorded in the past 30 days in Butte County, and the 15th this year in the Valley.

While Sacramento County has less exposure to these toxic al­gae than other re­gions in Cal­i­for­nia, lo­cal lakes are not safe from HAB exposure either, ac­cord­ing to a re­port by the Sacramento En­vi­ron­men­tal Com­mis­sion. “There is present a risk which may in­crease with higher tem­per­a­tures, more fre­quent low flow con­di­tions, and higher fre­quency of drought,” the com­mis­sion warned in 2016.

In 2017, La­guna Joaquin in Ran­cho Muri­eta and the Stone Lakes na­tional wildlife refuge in south­ern Sacramento County were af­fected by HABs. And just last sum­mer, HABs were de­tected in Sacramento Lake near the Freeport In­take, in the Port of West Sacramento near the Washington Lake en­trance, and in Ar­cade Lake.

The state’s Wa­ter Qual­ity Mon­i­tor­ing Council col­lects and maps reports of HAB-re­lated in­ci­dents, pro­vid­ing a bet­ter un­der­stand­ing of which ar­eas are at greater risk of in­fes­ta­tion. How­ever, the council em­pha­sizes that the “map only shows lo­ca­tions where harm­ful al­gal blooms (HABs) have been vol­un­tar­ily re­ported... [and] a wa­ter­body with no data is not an in­di­ca­tion that a bloom is not present.”

The com­mis­sion iden­ti­fied 10 wa­ter­ways in the greater Sacramento area that pose a higher risk of HAB exposure:

• Amer­i­can River

• Sacramento River

• Co­sumnes River

• Mor­ri­son Creek Group

• East Drainage Canal/Steel­head

• Creek/Dry Creek/Ar­cade Group • Deer Creek Group

• North Fork Bad­ger/La­guna Creek/Dead­man/Bear Slough Creek

• Delta wa­ter­ways and sloughs • Fol­som Lake

HABs have ex­isted for mil­lions of years and are es­sen­tial to the fresh­wa­ter ecosys­tem, ac­cord­ing to a news re­lease by the Butte County Public Health Depart­ment. How­ever, since HABs thrive in “warm weather, stag­nant wa­ter flows and ex­ces­sive nu­tri­ent in­puts,” more re­cent weather patterns caused by climate change and pol­lu­tion are fa­vor­ing their growth.

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.