diff --git a/TODO b/TODO
index 6ecb9d4067..b274949154 100644
--- a/TODO
+++ b/TODO
@@ -43,9 +43,10 @@ HIGH-PRIORITY (must be done to support SETI@home)
         returns a file with list of scheduler address
         and email address of "problems" contact
 
-- implement and test hi/lo water mark scheme
-    - core client must estimate how much work it has left,
-        based on %done (if available) and time estimates
+- complete client side and test hi/lo water mark scheme
+    - initialize rsc_fpops and rsc_iops in client WORKUNIT 
+    - ensure server sends correct number of work units
+    - check client requests correct number of seconds of work
 
 - measure hardware parameters: CPU speed, #CPUs, memory, disk
     - define CPU benchmarks
diff --git a/checkin_notes b/checkin_notes
index 6cad78b2ce..19e6bb28ae 100755
--- a/checkin_notes
+++ b/checkin_notes
@@ -329,6 +329,13 @@ Eric Heien    June 03, 2002
         parse.h (removed, uses lib version now)
         Makefile.in
 
+Michael Gary	June 04, 2002
+    - Added server side water level functionality, now sends as many work units
+	as necessary to fill the time requested. 
+
+    sched/
+	handle_request.C
+
 Eric Heien   June 06, 2002
     - Changes and additions made to begin porting to Windows.
     - This code will compile on Windows, but is not quite fully functional.
@@ -352,3 +359,23 @@ Eric Heien   June 06, 2002
 	md5.c
 	parse.C
 
+Michael Gary	June 06, 2002
+    - Added client side water level functionality.
+    - Added rsc_fpops and rsc_iops to the client WORKUNIT struct, bun not yet
+	functional since not initialized.
+    - Test scripts to check water level functionality, including minima and
+	maxima. Test scripts are based on test_prefs.php. 
+
+    client/
+	client_state.h
+	cs_scheduler.C
+	client_types.h
+    test/
+	max_water_prefs.xml
+	min_water_prefs.xml
+	normal_water_prefs.xml
+	test_max_water_prefs.php
+	test_min_water_prefs.php
+	test_normal_water_prefs.php
+
+
diff --git a/client/client_state.h b/client/client_state.h
index b272a1ca6b..a5ffa710d3 100644
--- a/client/client_state.h
+++ b/client/client_state.h
@@ -90,6 +90,8 @@ private:
     bool garbage_collect();
     int make_scheduler_request(PROJECT*, int);
     void handle_scheduler_reply(PROJECT*);
+    double estimate_duration(WORKUNIT*);
+    double current_water_days();
 
     // the following could be eliminated by using map instead of vector
     //
diff --git a/client/client_types.h b/client/client_types.h
index e64cf54856..113257e501 100644
--- a/client/client_types.h
+++ b/client/client_types.h
@@ -130,6 +130,8 @@ struct WORKUNIT {
     APP* app;
     APP_VERSION* avp;
     int ref_cnt;
+    double rsc_fpops; //needs to be initialized
+    double rsc_iops; //needs to be initialized
 
     int parse(FILE*);
     int write(FILE*);
diff --git a/client/cs_scheduler.C b/client/cs_scheduler.C
index 0661da4a31..3e30ce68f4 100644
--- a/client/cs_scheduler.C
+++ b/client/cs_scheduler.C
@@ -33,16 +33,30 @@
 // quantities like avg CPU time decay by a factor of e every week
 #define EXP_DECAY_RATE  (1./(3600*24*7))
 
-// TODO: implement hi/lo water mark scheme
+//estimates amount of time a workunit will take to complete
 //
-bool CLIENT_STATE::need_work() {
-    unsigned int i;
+double CLIENT_STATE::estimate_duration(WORKUNIT* wup) {
+    return wup->rsc_fpops/host_info.p_fpops + wup->rsc_iops/host_info.p_iops;
+}
 
+//estimates the number of days of work remaining
+//
+double CLIENT_STATE::current_water_days() {
+    unsigned int i;
+    double seconds_remaining=0;
     for (i=0; i<results.size(); i++) {
         RESULT* rp = results[i];
-        if (!rp->is_compute_done) return false;
+        if (rp->is_compute_done) continue;
+	if (rp->cpu_time > 0)
+	    seconds_remaining += (estimate_duration(rp->wup) - rp->cpu_time);
+	else
+	    seconds_remaining += estimate_duration(rp->wup);
     }
-    return true;
+    return (seconds_remaining * 86400);
+}
+
+bool CLIENT_STATE::need_work() {
+    return (current_water_days() <= prefs.low_water_days);
 }
 
 void CLIENT_STATE::update_avg_cpu(PROJECT* p) {
@@ -142,6 +156,7 @@ int CLIENT_STATE::make_scheduler_request(PROJECT* p, int work_req) {
 
 // manage the task of maintaining a supply of work.
 //
+// todo: determine how to calculate current_water_level
 bool CLIENT_STATE::get_work() {
     PROJECT* p;
     int retval;
@@ -158,7 +173,8 @@ bool CLIENT_STATE::get_work() {
                 }
                 return false;
             }
-            retval = make_scheduler_request(p, 1000);
+            retval = make_scheduler_request(p, 
+		  (int)(prefs.high_water_days - current_water_days())*86400);
             scheduler_op.init_post(
                 p->scheduler_url, SCHED_OP_REQUEST_FILE, SCHED_OP_RESULT_FILE
             );