8 I have had the advantage of reading in draft the reasons of Callaway J.A. I agree with his Honour that the appeal should be dismissed. I would add the following to what his Honour has said.
9 The centrepiece of the agreement of 30 July 1999 was the relinquishing by the appellants of the right to irrigation water for what was to become Lot 1 of the sub-division. I consider, given that context, that the meaning of clause 6 is clear. The respondent thereby undertook that the appellants' right of drainage from their land was not to be reduced by the circumstance that they were relinquishing the irrigation right which would otherwise attach to the proposed Lot 1. That was the interpretation placed upon clause 6 by the learned trial judge. Rightly so, in my respectful opinion.
10 Such a construction accords with the circumstances which attended the preparation and execution of the document - though strictly the same need not be considered. Thus -
• There seems to be no doubt that, prior to and at the time when the agreement was executed, the appellants were enjoying a "right" of discharging as much water from their land, and at so fast a rate, as the diameter of the pipe which led from their property to the respondent's drainage channel would permit. The evidence showed, as to rate, that discharge was possible at up to 23 litres per second.
• It seems very clear that the appellants wished to ensure that by giving up their right to irrigation water for the proposed Lot 1 they did not lose their "right" to discharge drainage water into the respondent's drainage channel. That is, they perceived, a linkage between the two rights.
• It also seems very clear that the appellants wished to ensure, as a subtext of not losing their "right" to discharge drainage water, that the status quo be retained. Hence their objection to the second draft version of the agreement, which referred to discharge "at the current rural rate".
• For its part, it seems to me, the respondent was content that the status quo as to drainage should not be affected by the appellants relinquishing the right to have irrigation water for the proposed Lot 1.
11 In my opinion the "right" of drainage referred to in clause 6 should be understood to refer to the then-existing situation; and not to a discharge limit of 1.2 litres per second per hectare. Such limit was established as a policy of the respondent. But the appellants did not know that; and it had never been applied to drainage from their land.
12 So to construe "right" in clause 6 is to give the word a variable meaning where used from time to time in the agreement. But the document was drawn by laymen; and in my opinion that is the sense of the clause, considered in context. I add that if regard were had to the circumstances which I mentioned in [10], my opinion would be reinforced.
13 The appellants would have it that by clause 6 the respondent committed itself to receive drainage from their property at whatever rate the discharge pipe would permit - without limit as to time and without regard to the possibility of change of circumstances. It is wholly improbable that such an agreement was reached. Particularly that is so where the status quo was so obviously at odds with the respondent's discharge policy.
14 In the event, circumstances did change. The respondent was called upon to consider a drainage plan formulated in respect of Lot 1 in the context of a proposed commercial development of that lot. It is not in point that the development was in contemplation when the agreement of 30 July 1999 was executed. Asked to consider an actual drainage plan, the respondent resolved to implement its discharge rate policy; requiring, so far as was necessary, that a retardation basin be established to ensure that the discharge rate did not exceed the limit set by such policy. It was not disabled from so acting. Implementation of the policy did involve a reduction in the status quo as to drainage; but one not deriving from the agreement. There was no breach of the agreement, actual or threatened, thereby.