Cypress Creek Basin Clean Rivers Program Nutrient Special Study Update Report – May 16, 2007 Roy...

Cypress Creek Basin Clean Rivers Program

Nutrient Special Study

Update Report – May 16, 2007

Roy Darville

Study Objectives

• determine the quantities, seasonal patterns and source watersheds of nutrients (nitrogen and phosphorus) presently being supplied to plant and microbial populations in Caddo Lake over an annual cycle • support the development of a nutrient budget to assess the trophic status (i.e., stage of reservoir eutrophication or nutrient enrichment) of Caddo Lake in comparison with similar systems within the Cypress Creek Basin and the surrounding area

Parameters Collected

• field: water temperature, dissolved oxygen, pH, specific conductivity• flow: USGS & USACE internet data (except at James Bayou

CR3312)• nitrogen – nitrate• nitrogen – nitrite• total Kjeldahl nitrogen• ammonia nitrogen• phosphorus• total organic carbon• chloride

Study Sampling

• 6 sites 1) Willow Pass Spillway2) James Bayou CR33123) Black Cypress SH494) Big Cypress SH435) Little Cypress US596) Big Cypress Below Lake O’ the Pines dam

• 19 sampling dates• First sample July 13, 2006• Last sample May 6, 2007

Willow Pass spillway –

Jan 28, 2007

5,300 cfs

Caddo spillway – Jan 25, 2007

7,300 cfs

James Bayou CR3312

May 6, 2007

Little Cypress Bayou – US59

May 6, 2007

632 cfs

Black Cypress – SH49

May 6, 2007

239 cfs

Big Cypress – SH43

May 6, 2007

906 cfs

Big Cypress – Below L.O.P.

May 6, 2007

35 cfs

Big Cypress – Below L.O.P. February 1, 2007

1,660 cfs

Sample dates

Sample dates